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ANALYSIS OF FACTORS AFFECTING POPULATION VIABILITY AND REINTRODUCTION ATTEMPTS
OF NATIVE MAMMALS IN ACADIA NATIONAL PARK
A Final Report Submitted To:
National Park Service
under
Interagency Agreement IA 1600-0-9006
Amendments # 1, 2
By
MaryEllen Chilelli Maine Cooperative Fish and Wildlife Research Unit
University of Maine Orono, Maine 04469-5755
James R. Gilbert Department of Wildlife
University of Maine Orono, Maine 04469-5755
Brad Griffith U.S. Fish and Wildlife Servicel
Alaska Fish and Wildlife Research Center Fairbanks Field Office Fairbanks, AI( 99701
and
AllanF. O'Connell, Jr. Cooperative Park Studies Unit
National Park Servicel
Orono, Maine 04469-5755
25 April 1994
lreorganized under National Biologcial Survey
FINAL REPORT ANALYSIS OF FACTORS AFFECTING POPULATION VIABILITY AND
REINTRODUCTION ATTEMPTS OF NATIVE MAMMALS IN ACADIA NATIONAL PARK
MaryEllen Chilelli, Maine Cooperative Fish and Wildlife Research Unit, University of Maine, Orono 04469-5755
James Gilbert, Department of Wildlife, University of Maine, Orono 04469-5755 Brad Griffith, U.S. Fish and Wildlife Service, Alaska Fish and Wildlife Research Center, Fairbanks
Field Office, Fairbanks, AK 99701 Allan O'Connell, National Park Service, Cooperative Park Studies Unit, University of Maine, Orono
04469-5755 EXECUTIVE SUMMARY
With escalating habitat fragmentation, native wildlife populations will become increasingly restricted to disjunct habitats. The ability of National Parks to sustain viable populations of wildlife species in habitat patches needs to be evaluated. We used stochastic simulation modeling to assess potential endangerment for small free-ranging or reintroduced populations of mammals based on life history characteristics, population size, environmental variation, and habitat patch size. Viability of simulated populations of mammals was based on an arbitrary definition of minimum viable population: < 50% probability of extinction in 50 years. We focused our analyses on Acadia National Park (ANP) and surrounding land located on Mount Desert Island along the coast of Maine. A species of special management concern to ANP was selected from 3 life history types: 1) southern bog lemming (Synaptomys cooperi), 2) fisher (Martes pennanti), and 3) black bear (Ursus americanus) .
Population viability of southern bog lemmings and strategies for their translocation were influenced by the season (summer or winter) and year within the 3-year population cycle that the population was initiated. Summer translocation programs were successful at lower founder population sizes than winter programs. Interconnecting habitat fragments are needed to maintain a viable metapopulation structure for southern bog lemmings.
Because trapping is permitted on land holdings adjacent to ANP and based on fisher home range sizes, any fisher within the park will be vulnerable to trapping. Viability of a fisher population on Mount Desert Island and within Acadia National Park requires trapping mortality < 0.22 for juveniles (ad M: <0.15, ad F: <0.07). The mean population size in simulation year 50 reflects a range (12-22 fishers) highly vulnerable to the effects of demographic and environmental stochasticity. Any establishment of fisher on Mount Desert Island would have to be considered part of a viable, connected mainland population. With a hypothetically increasing fisher population on the nearby mainland, translocating fisher to ANP might result in quicker reestablishment of a breeding population of fishers on ANP than would occur from relying solely on the dispersal of young from the adjoining mainland.
Black bear populations are highly sensitive to changes in female survival rates. Viable populations were not maintained with female survival rates lower than 0.76 for O-year-old bears and 0.86 for 2:..1-year-old bears. Simulated black bear populations on Mt. Desert Island are not of sufficient size to maintain genetic vigor. Any black bear population on Mount Desert Island would have to be considered part of a viable mainland population.
Our analyses and results allow quantitative evaluation of the ability of a fragmented park to support native mammals and identify reintroduction strategies most likely to succeed. The estimates derived from these simulations may be used to identify local populations at risk, set management goals for population size, number of populations, and habitat fragment size, estimate the probability of reintroduction success, and to help in prioritizing research and management options based on population risk and potential for successful reintroduction. Additionally, these analyses can provide data critical for deriving recovery goals for endangered and threatened species that will ensure their viability.
Chilelli et al.
TABLE OF CONTENTS
Analysis of factors affecting population viability and reintroduction attempts of native mammals in Acadia National Park.................................................................................. J
Tables
Methods........................................................................................................ 3 Strata ................................................................................................. . Simulations .......................................................................................... .
Results ......................................................................................................... . Discussion ................................................................................................... . Literature Cited ............................................................................................. .
3 5 9
13 17
1. Three strata of mammal species based on generalized life history strategies........... ......... 22
2. Vital rates for southern bog lemming (Synaptomys cooperi), Life History Strata 1 mammaL........................................................................................... 23
3. Vital rates for fisher (Martes pennanti), Life History Strata 2 mammal.......................... 24
4. Vital rates for black bears (Ursus americanus), Life History Strata 3 mammaL ............... 25
5. General management recommendations for 3 native mammals at Acadia National Park (ANP), Maine.............................................................................. 26
Figures
1. Simulated probability of extinction for southern bog lemmings (Synaptomys coopen), Life History Strata 1 mammal. Simulated population initiated in Winter, Year 1 of 3-year population cycle............................................... 27
2. Simulated probability of extinction for southern bog lemmings (Synaptomys coopen), Life History Strata 1 mammal. Simulated population initiated in Summer, Year 1 of 3-year population cycle........................... ....... ... ........ 28
3. Simulated probability of extinction for southern bog lemmings (Synaptomys coopen), Life History Strata 1 mammal. Simulated population initiated in Winter, Year 2 of 3-year population cycle................... .... ...... .. .. ... . .. ........ 29
4. Simulated probability of extinction for southern bog lemmings (Synaptomys coopen), Life History Strata 1 mammal. Simulated population initiated in Summer, Year 2 of 3-year population cycle.................................. ........... 30
5. Simulated probability of extinction for southern bog lemmings (Synaptomys coopen), Life History Strata 1 mammal. Simulated population initiated in Winter, Year 3 of 3~year population cycle............................................... 31
Chi/elli et al.
6. Simulated probability of extinction for southern bog lemmings (Synaptomys cooperi), Life History Strata 1 mammal. Simulated population initiated in Summer, Year 3 of 3-year population cycle............................................. 32
7. Simulated probability of extinction for southern bog lemmings (Synaptomys coopen), Life History Strata 1 mammal. Simulated population initiated in Winter, Years 1, 2, and 3 of 3-year population cycle................................. 33
8. Simulated probability of extinction for southern bog lemmings (Synaptomys cooperi), Life History Strata 1 mammal. Simulated population initiated in Summer, Years 1, 2, and 3 of 3-year population cycle ................................ 34
9. Mean population size of simulated viable populations of southern bog lemmings (Synaptomys cooperi), Life History Strata 1 mammal................................................ 35
10. Simulated probability of extinction for fishers (Martes pennantz), Life History Strata 2 mammal. Populations simulated with mortality during trapping season: juv = 0.25, ad M = 0.17, ad F = 0.08............................................................... 36
11. Simulated probability of extinction for fishers (Martes pennantz), Life History Strata 2 mammal. Populations simulated with mortality during trapping season: juv = 0.22, ad M = 0.15, ad F = 0.07............................................................... 37
12. Simulated probability of extinction for fishers (Martes pennantz), Life History Strata 2 mammal. Populations simulated with mortality during trapping season: juv = 0.16, ad M = 0.11, ad F = 0.05............................................................... 38
13. Simulated probability of extinction for fishers (Martes pennantz), Life History Strata 2 mammal. Populations simulated with no trapping mortality, nontrapping mortality M = 0.75 F.......... ................... ......................................................... 39
14. Simulated probability of extinction for fishers (Martes pennanti), Life History Strata 2 mammal. Populations simulated with no trapping mortality............................. 40
15. Simulated probability of extinction for black bears (Ursus americanus), Life History Strata 3 mammal. Populations simulated with x survival « l-year-old, 2::,1-year old): M = (0.40,0.60), F = (0.80,0.90); x litter size = 2.3.......................... 41
16. Simulated probability of extinction for black bears (Ursus americanus), Life History Strata 3 mammal. Populations simulated with X survival ( < l-year-old, 2::,1-year old): M = (0.36,0.54), F = (0.80,0.90); X litter size = 2.3.......................... 42
17. Simulated probability of extinction for black bears (Ursus americanus), Life History Strata 3 mammal. Populations simulated with X survival ( < l-year-old, 2::,1-year old): M = (0.32,0.48), F = (0.80,0.90); X litter size = 2.3.......................... 43
Chilelli et al.
18. Simulated probability of extinction for black bears (Ursus americanus), Life History Strata 3 mammal. Populations simulated with X survival « 1-year-old, 2:..1-year old): M = (0.40,0.60), F = (0.76,0.86); X litter size = 2.3.......................... 44
19. . Simulated probability of extinction for black bears (Ursus americanus), Life ·~History Strata 3 mammal. Populations simulated with X survival « 1-year-old,
i:.1-year old): M = (0.40,0.60), F = (0.76,0.86); X litter size = 2.07........................ 45
20. Simulated probability of extinction for black bears (Ursus americanus), Life History Strata 3 mammal. Populations simulated with X survival ( < 1-year-old, 2:..1-year old): M = (0.40,0.60), F = (0.76,0.86); X litter size = 2.00........................ 46
21. Simulated probability of extinction for black bears (Ursus americanus), Life History Strata 3 mammal. Populations simulated with x survival « 1-year-old, :> I-year old): M = (0.40,0.60), F = (0.72,0.81); X litter size = 2.3.......................... 47
22. Simulated probability of extinction for black bears (Ursus americanus), Life History Strata 3 mammal. Populations simulated with x survival « 1-year-old, 2:..1-year old): M = (0.40,0.60), F = (0.80,0.90); X litter size = 2.3, during a 1, 2, or 4-year translocation program................................................................... 48
23. Simulated probability of extinction for black bears (Ursus americanus), Life History Strata 3 mammal. Populations simulated with x survival « l-year-old, 2:..1-year old): M = (0.40,0.60), F = (0.76,0.86); X litter size = 2.3, during a 1, 2, or 4-year translocation program.... ...... ... ...... .............. ........ .... ......... .... ..... ..... 49
24. Simulated probability of extinction for black bears (Ursus americanus), Life History Strata 3 mammal. Populations simulated with X survival « 1-year-old, 2:..1-year old): M = (0.40,0.60), F = (0.76,0.86); X litter size = 2.0, during a 1, 2, or 4-year translocation program................................................................... 50
Appendixes
1. References used to derive life history characteristics of mammals................ ................. 51
II. Documentation for TRANSLOC: a population simulation model.................................. 75
ANALYSIS OF FACTORS AFFECTING POPULATION VIABILITY AND REINTRODUCTION ATTEMPTS OF NATIVE MAMMALS
IN ACADIA NATIONAL PARK
With escalating habitat fragmentation, native wildlife populations will become
increasingly restricted to disjunct habitats. The role of National Parks in providing relatively
unexploited habitat patches will increase. Habitat patches will contain smaller populations of
wildlife species than large contiguous areas of habitat, and these reduced populations will be
more susceptible to extinction due to stochastic events (Terborgh and Winter 1980, Shaffer
1981, Goodman 1987, Lande 1988). In fact, many species that were historically present in
North American National Parks may have become extinct (Newmark 1986, 1987; but see
Quinn et al. 1988) .
. Viability of small relict populations is extremely sensitive to stochastic events
(Terborgh and Winter 1980, Shaffer 1981, Goodman 1987, Lande 1988). From theoretical
studies we know that populations are more likely to persist when they are large, the rate of
population increase is high, and the effect of competition is low (MacArthur and Wilson
1967). Low variance in the rate of increase (Leigh 1981), presence of refugia (Goodman
1987), reduced environmental variation (Leigh 1981, Ewens et al. 1987), herbivorous food
habits (Crawley 1986), and high genetic diversity among founders (Franklin 1980,
Schoenwald-Cox et al. 1983,Soule 1986, Geist 1987, Lande and Barrowclough 1987) may
also increase population persistence. Empirical analyses of native wildlife translocations
(Griffith et al. 1989) and non-native species invasions (Newsome and Noble 1986, O'Connor
1986) confirm most of these general predictions and additionally show that high habitat
quality in the core of the historical species range enhances population viability.
Translocation programs (introductions, reintroductions, and augmentations) are often
Chilelli et al.
viewed as remedies to localized extinctions but they are expensive (Cade 1986) and take
calculated risks with valuable members of species that are often relatively rare. Although
translocations of native game species are relatively successful, trans locations of threatened,
endangered, or sensitive species have reasonable probability of success only under
exceptionally favorable circumstances (Griffith et al. 1989).
Effective evaluation of the ability of National Parks to sustain viable populations of
wildlife species requires 2 analyses. First, estimates of extinction probabilities for small
populations of various species are needed; and second, estimates of success rates of
reintroduction programs are necessary.
Extinction probabilities may be approximated from computer simulations of the effect
of stochastic variation on the growth and persistence of model populations. Simulation
models have been used to estimate extinction probabilities for free-ranging mammals (e.g.
Watts and Conley 1981, Shaffer 1983, Suchy et al. 1985) and, ideally, they could be used to
assess the population sizes and vital rates necessary to ensure persistence on a species by
species basis. These population characteristics could be used as management indicators.
We used stochastic simulation modeling to assess potential endangerment for small
free-ranging or reintroduced populations of mammals based on life history characteristics.
This work provides first approximations towards assessing population viability based on park
size and fragmentation. We focused our analyses on Acadia National Park, located on
Mount Desert Island (282 km2) along the coast of Maine. The island is characterized by
parcels of park land interspersed among land subject to a variety of management practices,
resulting in substantial fragmentation.
2
Chi/elli et al.
METHODS
Strata
Mammals were stratified based on life history characteristics: reproductive strategy
(generation time), litter size, home range size (small or large relative to habitat fragment
size), area use patterns (overlapping vs. non-overlapping) and vital rates. Data on life
history characteristics were compiled from references to field studies of population dynamics
in mammals (Appendix 1).
3
We focused our analyses on 3 strata of mammalian species, representing a broad
range in life history characteristics. Strata 1 is characterized by those species with very short
generation times and multiple litters per year. Their habitat requirements .are met in a very
small area and their population has a colonial or territorial structure (Table 1). This strata
includes species in Geomyidae, Heteromyidae, Leporidae, Muridae, and Sciuridae. Strata 2
consists of those mammals that produce their first litter at 1-2 years of age, with only one
litter per year. These mammals have a territorial social structure, being intrasexually
exclusive for at least one sex (Table 1). Several species within Mustelidae and Felidae
comprise Strata 2. Strata 3 is characterized by those mammal species that do not produce
their first young until after 2 years of age and generally do not produce litters every year
(Table 1). There is extensive intrasexual overlap in the home range structure of at least one
sex. These life history characteristics are those for some species in Ursidae and Felidae.
A species of special management concern to Acadia National Park (ANP) was
selected from each of these 3 highlighted strata: Strata 1 - southern bog lemming
Chilelli et al.
(Synaptomys cooperi), Strata 2 - fisher (Martes pennanti) , and Strata 3 - black bear (Ursus
americanus). These 3 species are locally rare within ANP (National Park Service 1992).
4
Southern Bog Lemming- Gaines et al. (1977) provided the only detailed documented
survival and reproductive rates for southern bog lemming (Table 2). We based the vital rates
used in our simulations on these rates. A cycle period of 3 years with a winter (Nov-Feb)
and summer (Mar-Oct) season was delineated for the southern bog lemming (Gaines et al.
1977), with a generation time of approximately 67 days (Nowak and Paradiso 1983).
Sex- and age-specific vital rates differed according to cycle year and season (Table 2).
Proportion of females lactating by season and year provided estimates of probability of
successfully giving birth. Mean litter size is 3, ranging 1-8 (Nowak and Paradiso 1983).
Few microtines live > 2 years (Johnson and Johnson 1982). The maximum population
density reported for southern bog lemmings is 50/ha (Gaines et al. 1977).
Acadia National Park is at the northern limit of the range for southern bog lemming
(Hamilton and Whitaker 1979), with vegetative communities reflecting the species' habitat
requirements (Getz 1961, Nowak and Paradiso 1983, Linzey 1984, Danielson and Gaines
1987, Danielson and Swihart 1987). The southern bog lemming has been listed in historic
records of small mammals on Mount Desert Island (Manville 1960, Coman 1987, Garman
1991); however, the current status of this species within ANP is uncertain.
Fisher- We based our model inputs on vital rates estimated for fisher in Maine (Table
3). The range of home range sizes Arthur et al. (1989) determined for Maine (Table 3) are
similar to those in other parts of North America (Strickland et al. 1982, Douglas and
Strickland 1987). Fisher home ranges are intrasexually exclusive (Arthur et al. 1989), with
Chilelli et al.
overlap between the sexes. Corpora lutea range 1-5 (Shea et al. 1985), with a 50:50 sex
ratio at birth (Strickland et al. 1982). Females breed at 1 year, and the effective age of fIrst
breeding for males is 2 years (Strickland et al. 1982, Douglas and Strickland 1987).
5
The fisher was probably extirpated from Mount Desert Island around the tum of this
century, prior to establishing ANP. The reason for its extirpation is uncertain but probably
resulted from overtrapping and habitat loss (National Park Service 1992). Furbearer trapping
still occurs on nonpark property, which is interspersed with parklands.
Recently, there have been 2 isolated sightings, 1988-90, of fisher and their signs
within the park (M. Saeki and D. I. Harrison, Univ. Maine, pers. commun). These limited
sightings likely represent transient individuals from the mainland.
Black Bear- Black bears occur in North America from Maine to Alaska to Arizona
(Appendix 1). To simulate bear populations in Acadia National Park, we restricted our
range of vital rates to those found in eastern populations (Table 4). Bears in Maine (C. R.
McLaughlin, Me. Dept Inland Fish. and Wildl., unpubl. data) and Massachusetts (Elowe and
Dodge 1989) have home ranges that overlap extensively, especially among a sow and her
grown female offspring. Male subadults may widely disperse, often leaving their birth area.
Black bears are sighted infrequently within ANP.
Simulations
We used the stochastic simulation model TRANSLOC (Chilelli et al. 1992, Appendix
2) to evaluate the effect of initial population size, and mean and variance for survival and
fecundity rates on population viability and alternate reintroduction strategies among selected
life history strata for mammals (Tables 2-4). Traditional population viability analysis (PVA)
Chilelli et at. 6
consider a population extinct when only 1 organism or one sex remains (Shaffer 1983,
Marcot and Holthausen 1987, North et al. 1988, Lacy 1989). We defmed extinction in our
simulations as N males or N fc:males = 0 by year 50. We identified population characteristics
indicating a 50 % probability of extinction (P J within 50 years for each representative species
inhabiting a range of habitat fragment sizes.
Habitat fragmentation was implemented by imposing a ceiling on maximum
population size for each scenario determined by the species life history characteristics (social
organization, home range size, degree of overlap in home ranges) and the size of the
simulated habitat fragment. If the population exceeded this maximum size, juveniles were
removed from the population simulating mortality or dispersal. Juveniles eliminated from the
population were stochastically distributed between sexes. This removal of juveniles
continued until the population was within the habitat fragment bounds. Because we were
simulating isolated popUlations, there was no immigration and losses reflected mortality or
dispersal into adjacent unsuitable habitat.
To ensure that estimates of extinction probabilities stabilized, we replicated each
scenario 800 times to obtain 2.95 % probability that the estimate of Pe = f> + <..::;, 0.025).
Initial population age ratios were set proportional to the survivorship curves for each
scenario. Sex ratio at birth was determined stochastically based on a 50:50 sex ratio.
Scenarios modeled populations with initial population sizes within the range of 10-200.
Both demographic and environmental variation were incorporated in the simulated
vital rates (Appendix 2). We did not implement a density dependence response in vital rates
because it tends to reduce net variance in these rates and thus lower estimates of extinction
Chilelli et al.
(Ginzburg et al. 1990). Generally, data were not available to delineate stochastic
catastrophes or cyclic patterns in vital rates. Incorporating these factors would increase
estimates of extinction rates for small populations (e.g., Lacy 1991) because net variance
would be increased. In our simulations, survival rates for all age classes (M and F) were
correlated and reproductive rates were not correlated with survival rates, unless a different
correlation pattern among vital rates was supported from the literature. Strata-specific
revisions were made to TRANSLOC to simulate these different life history patterns
(Appendix 2).
7
Once we determined population levels and vital rates indicating 50 % chance of
extinction within 50 years, we simulated reintroduction programs. These translocation
scenarios incorporated at least: 1) three levels of number released in a single year, 2) three
levels of survival and fecundity, and 3) three program lengths releasing multiples of the
number of animals released in single year programs. No adjustment to year-of-release
mortality rates was required to realistically simulate success of mammal translocations
(Griffith et al. 1991).
Southern Bog Lemming- We modified TRANSLOC (TRNSLCMC: Appendix 2) to
incorporate the 3-year cycle in vital rates described by Gaines et al. (1977) (Table 2). Based
on life history characteristics of this species, we modeled 2 reproductive-survival subperiods
during the winter season (W) and 3 reproductive-survival subperiods during the summer
season (S) (1 reproductive-survival subperiod = 73 days). This revision to TRANSLOC
incorporated the seasonally polyestrus nature of the southern bog lemming. Maximum
longevity was set to 3 years, and maximum population density was 50 bog lemmings/ha
Chi/elli et al. 8
(Gaines et al. 1977). Because the actual distribution of habitat patches in ANP for southern
bog lemming was not available, simulated bog lemming populations were restricted to habitat
fragments ranging 0.5-30 ha.
Fisher- To model the area use pattern typified by fisher, we restricted population
growth based on sex-specific home range sizes for adults (Appendix 2). Annually, the
number of adult territories available for each sex was determined from sex-specific home
range sizes (incorporating environmental stochasticity (C. V.) into sex-specific means (Table
3) to reflect annual habitat quality) and the simulated habitat fragment. Home range sizes
were correlated between sexes. We used the total area of potential fisher habitat on Mount
Desert Island (235 km2) as the simulated habitat fragment.
Black Bear- Several modifications were made to TRANSLOC to model the life
history patterns of black bears (TRNSLCBB: Appendix 2). The quality of the fall food
supply influences annual survival of bears 2..1 yrs, but also greatly effects the proportion of
females successfully giving birth the following winter as well as the first year survival of
those cubs (Jonkel and McT.Cowan 1971, Rogers 1976, 1987; Pelton 1982, Beecham 1983,
Eiler et al. 1989, Elowe and Dodge 1989, Schwartz and Franzmann 1992). TRANSLOC
was modified to reflect this correlation pattern among reproductive rate and survival of cubs
(Appendix 2). We modeled a 2-year reproductive cycle for black bears, with females
becoming pregnant in one year and producing cubs in the following year. Because cubs
remain with their mother for, 1 year, enhancing cub survival (Jonkel and McT.Cowan 1971,
Jonkel 1978), we reduced survival of cubs 10% (Knight and Eberhardt 1985) if they became
orphans during their first year. With the extensive overlap in home ranges, we simulated
Chilelli et al.
maximum population density similar to that modeled for southern bog lemmings. Maximum
population densities of simulated black bear populations ranged 0.15-0.45 bears/lan2 (Abler
1983, Smith 1985, Elowe and Dodge 1989, Hellgren and Vaughan 1989) (Table 4). We
used the total area of potential black bear habitat on Mount Desert Island (250 lan2) as the
size of the simulated habitat fragment. The simulated lower survival rates for male cubs
versus female cubs reflects the greater mortality rate for males (Elowe and Dodge 1989,
Schwartz and Franzmann 1992) and their tendency for dispersal away from their birth area
(Rogers 1987, Schwartz and Franzmann 1992).
RESULTS
Viability of simulated populations of mammals is based on an arbitrary definition of
minimum viable population (mvp): < 50% probability of extinction in 50 years.
9
Southern Bog Lemming- The survival rates reported by Gaines et al.(1977) were
listed as minimum survival rates per 14 days (Table 2) and produced 100% probability of
extinction in our simulations. However, if we used these reported rates to reflect vital rates
in each reproductive-survival subperiod, our simulated rates then approximated those
reported for other Microtus spp. based on life history stage (Golley 1961, Johnson and
Johnson 1982). All of our simulation experiments for bog lemming used these reported vital
rates (Table 2) as vital rates per reproductive-survival subperiod.
The minimum habitat fragment size needed to produce < 50 % Pc varied with level of
environmental variation (EV): low EV required 2..4 ha, medium EV required L.. 7 ha of
Chilelli et al. 10
habitat (Figs. 1-8). Generally, populations simulated in high EV did not produce populations
where Pe < 50% (Figs. 1-8).
The minimum introduced population size required to produce populations where P e <
50% varied by season and year within the 3-year population cycle (cycle year = 1, 2, or 3;
Table 2). Minimum introduced populations ranged 35-125 lemmings under low EV and 17-
180 in medium EV simulations (Figs. 1-8). The mean population sizes in simulation years
48-50 (reflecting the 3 population levels in the 3-year population cycle) also varied by cycle
year and season in which the simulation was initiated and the EV level. In low EV systems,
mean population sizes per 4 ha habitat patch ranged 62-143 in the last 3 years of the
simulation. Because medium EV scenarios required larger habitat fragments, mean
population sizes per 7 ha patch ranged 90-231 in years 48-50.
There was a common pattern in the mean population size (years 1-50) in all successful
releases (Pe < 50%). After a period of relative stability in population size (years 10-40),
mean population size gradually declined during the last 10 years of the simulation. Three
examples of this pattern are presented (Fig. 9). This decline may be caused by the combined
effects of the cyclic pattern in vital rates with the influence of EV preventing population size
from stabilizing.
Fisher- The fisher population in Waldo County, Maine is heavily trapped and exhibits
a decreasing population size (Paragi 1990). Because trapping is permitted on land holdings
adjacent to Acadia National Park and based on fisher home range sizes (Arthur et al. 1989),
any fisher within the park will be vulnerable to trapping. If fisher are to be successfully
established on Mount Desert Island, their mortality during the furbearer trapping season
Chi/elli et al. 11
would have to be greatly reduced from that observed in Waldo County.
Fisher populations were simulated at several levels of reduced mortality during the
furbearer trapping season (Figs. 10-14). Mortality during the trapping season had to be
reduced to 0.25 for juveniles (ad M: 0.17, ad F: 0.08) to obtain <50% Pe, at initial
population sizes 2.55 and only under low environmental variability and low home range
variability (HRV) (Fig. 10). These successful simulations produced mean population sizes at
year 50 (poPso) of 13. Under medium EV, mortality rates needed to be reduced to 0.22 for
juveniles (ad M: 0.15, ad F: 0.07) in the trapping season for Pe < 50% (Fig. 11), with popso
ranging 12-15. Only when mortality during the trapping season was reduced to 0.16 for
juveniles (ad M: 0.11, ad F: 0.05) did fisher populations with high EV and high HRV obtain
Pe < 50% (Figs. 12-14). Populations reflecting a trapping season mortality of 0.16 for
juveniles (ad M: 0.11, ad F: 0.05) (Fig. 12) had popso ranging 13-18. In populations
simulated with no mortality during the trapping season (Figs. 13-14), popso for fisher on Mt.
Desert Island ranged 15-22, depending on the level of EV and HRV.
Translocation scenarios were simulated with program lengths ranging 1-5 years and
total number of fisher released to-100. We chose 3 vital rate scenarios with Pe < 50% as
the basis of these translocation experiments (1. 0.22 trapping mortality for juveniles [ad M:
0.15, ad F: 0.07], low EV, 40% HRV [Fig. 11]; 2. 0.16 trapping mortality for juveniles [ad
M: 0.11, ad F: 0.05], medium EV, 20% HRV [Fig. 12]; 3. no trapping mortality, male
survival = 75% female survival, medium EV, 20% HRV [Fig. 13]). In all simulated
translocation scenarios, increase in program length from 1 to 5 years had no effect on Pe
level or popso from that detennined for programs with a single release.
Chilelli et al. 12
Black Bear- Black bear simulations were initiated using rates reported for
Massachusetts as a baseline (male survival rates: 0 yr=O.4, 2.1 yr=0.6; female survival
rates: 0 yr=O.S, 2.1 yr=0.9, X littersize = 2.3 cubs) (Elowe and Dodge 1989, Elowe et al.
1991). At these initial vital rates, simulated populations of black bears had Pe < 50% at
densitiesrartging 0.25-0.45 bears/km2 for all levels of EV (Fig. 1's»):With POPSll ranging
60-11 0 bears ..
With a 10% reduction in male survival rates compared to Massachusetts (0 yr=0.36,
Ll yr=0.54), only populations simulated at densities ranging 0.35-0.45 bears/km2 had Pe <
50 % (Fig. 16), with popso stabilizing at SO-11 0 bears depending on simulated maximum
density. Additional reductions in male survival rates did not produce viable populations (Fig.
17). Even though Pe < 50% at high population density levels (Fig. 17), there was a
decreasing trend in x popUlation size during years 40-50.
A 5 % reduction in female survival rates compared to Massachusetts (0 yr=0.76, 2.1
yr=0.S6) produced viable populations at all densities and EV levels, except for populations
simulated at high EV and minimum density levels (Fig. IS). Depending on simulated
density, popso stabilized at 30-111 bears. Decreases in littersize did not effect population
viability at this level of female survival (Figs. 19-20). Even though a 10% reduction in
female survival rates (0 yr=0.72, 2.1 yr=O.SI) indicated viable populations for most EV
and density levels (Fig. 21), mean population levels were decreasing during the last 10 years.
Translocation programs for black bears were simulated at total founder population
sizes 20-S0 bears, released over 1, 2, or 4 years. Either 0% or 15% (McArthur 1981) of the
adult females were released with cubs. Three vital rate scenarios were simulated at 2 density
Chi/elli et al. 13
levels (0.25 and 0.45 bears/lan2) (Figs. 22-24). There was <5% difference in Pc levels
among bear translocations within a density and vital rate level. Lengthening the release
program or increasing the percentage of adult females released with cubs had little influence
on :Pc level; this difference became minimal at total founder population sizes 2..40 bears
(Figs. 22-24).
DISCUSSION
The year within the 3-year population cycle and season (S or W) (Table 2) influences
population viability of southern bog lemmings and strategies for their translocation. It is not
known what factors cause southern bog lemming populations to cycle (Gaines et al. 1977).
Microtine population cycles could be caused or influenced by an interaction of factors related
to the microtine population, vegetation, and predators (Pianka 1974, Smith 1974). During
the initiation of a release program, the phase of the bog lemming population (increase, peak,
decline [Gaines et al. 1977]) may be influenced by the cycle dynamics of the source animals
and by the dynamics of the ecosystem at the translocation site, with the interaction of
vegetation, other herbivores, and predators.
When initiating a translocation program for southern bog lemmings, phase in the
population cycle may not be known during the initial period of the program. Releasing
animals over 3 consecutive summers or winters obviates attempting to establish the
-population during the decline phase in the population cycle. Even though translocation
programs based on summer releases had similar probabilities of success as those with winter
Chilelli et at. 14
releases, summer programs were successful at lower founder population sizes because
survival of subadult females and reproductive rate were greater during 2 summer seasons.
The degree of environmental variation determined the minimum size of the habitat
fragment needed for successfully establishing a bog lemming population (low EV: 4 ha, med
EV: ·7 ha). Environmental variation is determined by the temporal fluctuation in habitat
parameters and populations of competitors, predators, parasites, and diseases (Shaffer 1981,
Lande 1988). For example, dramatic changes in habitat conditions (e.g. via fIre) or
significant changes in predator or competitor populations would result in medium to high EV
conditions. Another critical factor to consider for southern bog lemming populations, is the
degree EV is correlated between patches of a metapopulation (Gilpin 1987).
The decline in simulated mean population size observed in established populations of
southern bog lemmings may be reflective of the ephemeral nature of this species based on its
life history characteristics. This pattern indicates the need to create interconnecting habitat
fragments to maintain a viable metapopulation structure for bog lemming. Whether these
colonies would be synchronous or asynchronous in their population fluctuations is not known.
Usually, microtine fluctuations are synchronous over large geographic areas (Krebs and
Myers 1974). However, Gaines et al. (1977) described 2 populations of southern bog
lemmings, 400 m apart, that were asynchronous. If individual populations of bog lemmings
are asynchronous, new viable colonies of bog lemmings could be in a phase of establishment
as older colonies were declining. However, if these bog lemming populations are
synchronous, populations may need to be supplemented at a s.. 40-year interval (based on the
observed decline in mean population size) to minimize the probability of the metapopulation
Chilelli et ai. 15
dropping below the mvp level during decline phases. Long-term persistence of southern bog
lemming populations also will depend on maintaining genetic variation in addition to
monitoring the effects of demographic factors. Genetic variation within colonies can be
increased with the translocation of as few as 2 individuals at random into each subpopulation
per generation, provided the trarlsf~rred animals produce young (Lande and Barrowcloug;h~
1987).
Our simulation experiments show that the primary concern regarding the viability of a
fisher population on Mount Desert Island and within Acadia National Park is mortality during
the trapping season on lands adjacent to the park. Trapping mortality would have to be kept
below 0.22 for juveniles (ad M: 0.15, ad F: 0.07).
With the interspersion of parklands and private land holdings on Mount Desert Island
and the occurrence of furbearer trapping on nonpark property, trapping regulations would
have to be greatly restricted to produce this necessary low level in fisher mortality. Our
simulated trapping mortality of 0.22 for juveniles (ad M: 0.15, ad F: 0.07) represent a 65 %
reduction from the trapping mortality observed in Waldo County, Maine, where fisher are
heavily trapped (Krohn et al. 1994).
These trapping restrictions produce a mvp of fisher based on demographic and
environmental stochasticity. Lande (1988) argued that demography is more immediately
important than population genetics in determining minimum viable sizes of wild populations.
The simulated popso of 12-22 fishers, depending on mortality rates and environmental
-variability levels, is a population range highly vulnerable to the effects of demographic and
environmental stochasticity (Shaffer 1981, Lande 1988). A fisher population isolated to
Chilelli et al. 16
Acadia National Park or Mt. Desert Island would be critically threatened with extirpation
(Mace and Lance 1991) and would not be considered viable. Any establishment of fisher on
Mount Desert Island would have to be considered part of a viable, connected mainland
population.
Considering our simulation results and a hypothetically increasing fisher population on
the nearby mainland, translocating fisher to ANP might result in quicker reestablishment of a
breeding popUlation of fishers on ANP than would occur from relying solely on the dispersal
of young from the adjoining mainland. Any trans locations of fisher onto Mount Desert
Island would facilitate expansion of the species range in south-central Maine.
Black bear populations are highly sensitive to female survival rates (Knight and
Eberhardt 1985, Eberhardt 1990, Schwartz and Franzmann 1992). Viable populations were
maintained at male survival rates as low as 0.36 for O-year-old bears and 0.54 for
2..1-year-old bears. However, female survival rates lower than 0.76 for O-year-old bears and
0.86 for 2..1-year-old bears did not maintain population viability. Because of conflicting
indications of viability based on Pc levels versus mean population level, long-lived species
such as the black bear need to be simulated for longer periods (e.g. L100 years).
Our simulations indicate viable populations of bears at lower maximum density levels
(0.15 bears/km2) when female survival rates were reduced to 0.76 for O-year-old bears and
0.86 for 2::..1-year-old bears. A slightly greater rate of turnover in the female segment of the
population may have increased the opportunities for cubs to establish home ranges within the
-maternal population and, thus, benefitted population viability.
Simulated black bear populations are not of sufficient size to maintain genetic vigor
Chi/elli et al. 17
(Franklin 1980), with simulated popso ranging 35-111 bears depending on EV and maximum
popUlation density levels. Any black bear population on Mount Desert Island would have to
be considered as a segment of a viable mainland population.
Obviously, species with small habitat area requirements in relation to available park
habitat have a greater potential of producing isolated, viable populations within a national
park (e.g., southern bog lemming vs black bear or fisher). However, small patch size
requirements does not alone determine the prospects for viability, as demonstrated with the
southern bog lemming simulations. Species with cyclic patterns in vital rates may need
multiple populations and periodic releases to allow metapopulation survival while extirpation
and establishment of local populations continue.
Our analyses and results allow quantitative evaluation of the ability of a fragmented
park to support native mammals and identify reintroduction strategies most likely to succeed.
The estimates derived from these simulations may be used to identify local populations at
risk, set management goals for population size, number of popUlations, and habitat fragment
size, estimate the probability of reintroduction success, and to help in prioritizing research
and management options based on population risk and potential for successful reintroduction
(Table 5). Additionally, these analyses can provide data critical for deriving recovery goals
for endangered and threatened species that will ensure their viability (Tear et al. 1993).
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Chilelli et al. 22
Table 1. Three strata of mammal species based on generalized life history strategies. a
Characteristics Strata 1 Strata 2 Strata 3
Breeding system polygamous polygam9us polygamous
Generation time (yr) <1 1-2 >2
No. litters/yr >1 1 <1
Range young/F /yr 0-40 0-10 0-6
Max. longevity (yr) 5 15 30
Home range (km~ <1 1-100 5-600
Area use pattern territorial territorial- home range-or intrasexually intrasexual colonial exclusive overlap
aLife history characterisitics were derived from extensive literature search~ References are listed in Appendix 1.
Chi/elli et ale 23
Table 2. Vital rates for southern bog lemming (Synaptomys coopen), Life History Strata 1 mammal, from Gaines et ale (1977). Survival rates are minimum rates per 14 days. Sample sizes are in parentheses.
x Survival rates % Females male female
Season, Year lactating subad ad subad "- 'ad
Winter,Yrl 0.14(7) 0.20(15) 0.67(6) 0.56(9) 0.50(8)
Summer,Yrl 0.70(30) 0.45(11) 0.71(21) 0.38(13) 0.73(30)
Winter, Yr2 0.48(69) 0.74(38) 0.83(60) 0.46(46) 0.86(58)
Summer,Yr2 0.55(119) 0.47(30) 0.80(140) 0.58(36) 0.77(115)
Winter,Yr3 0.39(59) 0.66(56) 0.77(74) 0.57(42) 0.72(65)
Summer,Yr3 0.22(41) 0.64(14) 0.71(51) 0.82(17) 0.64(28)
Chi/elli et al.
Table 3. Vital rates for fisher (Martes pennantz), Life History Strata 2 mammal.
Life history parameter
Reproduction x litter size
2-yr-old F >2-yr-old F
P successfully giving birth 2-3-yr-old F 4-7-yr-old F >7-yr-old F
Survival Birth-first fall Juv (first fall to l-yr-old)
Nontrapping season Trapping season
Adult Male Nontrapping season Trapping season
Adult Female Nontrapping season Trapping season
Home range (km~ (x (range» Adult male Adult female
a(H. Frost, Univ. Maine, pers. commun.). b(Paragi 1990). C(Krohn et al. 1994). d(Arthur et al. 1989).
Value
0.58a
30.9 (10.6-78.2)d 16.3 (8.1-39.1)d
24
Chi/elli et at. 25
Table 4. Vital rates for black bears (Ursus americanus), Life History Strata 3 mammal.
Parameter
Litter X range sex ratio
Breeding success No. F loosing entire litter
First time mothers With prior litters
Age at 'first litter (yr)
X annual survival Cubs
Male Female
2.1-yr-old Male Female
Density (bear/km2)
a(Elowe and Dodge 1989). b(Elowe et al. 1991). cReferences listed in Appendix I.
Massachusettsa.b Eastern U.S.C
2.3 2.0-2.6 1-4 1-4 50M:50F 50M:50F
4 (of 7 F) o (of 15 F)
3 (4 of 10 F) 3-6 4 (5 of 10 F) 5 (1 of 10 F)
0.38-0.88 0.38 0.80
0.59 0.59-0.82 0.93 0.68-0.93
0.14 0.06-0.66
Chilelli et al. 26
Table 5. General management recommendations for 3 native mammals at Acadia National Park (ANP), Maine.
Mammal Life HistorY Strata Recommendations 1 2
Representative species southern bog lemming fisher (Synapt0mYs coopen) (Martes pennantl)
ANP of sufficient size yes noa
to maintain viable population
Local population in ANP status unknown not present at risk of endangerment
ANP population goal for 120 (4 ha habitat patch) not applicable probability of 200 (7 ha habitat patch) extinction < 0.5 by year 50
Goal number populations 4b < 1 (partial) to maintain within ANP
Minimum size of 4-7 ha >235 km2
habitat patch per population inANP
No. to translocate to 120 (1) 20 (2)C (1) establish (release (release population or over 3 over 1-5 yrs) (2) maintain consecutive viewing summers)
aSpecies should be considered part of a regional population. b < 0.05 probability of meta population extinction. CRequires viable connected population on mainland.
3
'_-n...-~,.,.._--.., .•• ~. __
black bear (Ursus americanus)
noa
not present
not applicable
< 1 (partial)
>250 km2
40 (2)C release over 1-4 yrs)
Chi/elli et al. 27
Fig. 1. Simulated probability of extinction for southern bog lemmings (Synaptomys cooperi), Life History Strata 1 mammal (polygamous < 1 yr generation, > 1 litterlyr, 0-40 younrJFlyr, maximum longevity = 5 yr, home range < 1 km2, territorial or colonial). Simulated population initiated in Winter, Year 1 of 3-year population cycle (Table 2). C.V. levels for vital rates (fecundity, sub adult survival, adult survival): low C.V. (0.05,0.05,0.05), medium C.V. (0.10,0.15,0.10), high c.v. (0.15,0.20,0.15). Populations restricted to habitat patches 1-30 ha (maximum population density = 50 southern bog lemmingslha). Viable populations «50% probability of extinction in 50 years) indicated by simulations below 0.50 probability of extinction line.
-
I I 40 80 120 160
-
200
r= '1111'11\
o 0.8 - "I\" .... """~ .. -.. - . I -J;: --.. --.:::::::-.......... 5 ha
CJr= 0.6- ......... _ .. ;;~I" ... - __ .. --------.. 6 h ..... "".... 1';. •••• , a--- - _______________ ------I ______________________________ ~-~--=-~--~~~~~~.~~ ... ~ ... ~ ... ~ ... ~ ... ; ...•... ~ ... ~7~h~a~~~~ .. ~ .. ~ ... ~ ... ~.··~···~·· .-S 0.4- -----------Sha,
~ - . I o 0.2- I c- . "i Medium C.V.
:.= 0.0 -1 I I J J I
~ 0 40 80 120 160 200 ~ 1.0,-------.----------------------------------------------~ e -~ 0.8-
"'_-... -.. ..... "" .. I\.,~ ..... ~~ ... ~:: .. ::::.- .... - ----- .. -. 12 ha
....... :." .... ""............... ... - -- - 4 h :-:-::-:---.:::=::=~~ .. r.::~:";;--_--:--------·1 a·-25-· h -- .... ------•••••••••••• '::~:a ..... -.-.----- a 0.6 - ............................... ::~::.:'I,.-.... ~::.
~------------------__ ---------------------------------------------~3~0~h~a-----~ 0.4= I 0.2- I
- High C.V. I . O.O;------r-----~I----.------.-I----TI-----,~----~----~I-----,~--~
o 40 80 120 160 200 Initial Population Size
Chi/elli et al. 28
Fig. 2. Simulated probability of extinction for southern bog lemmings (Synaptomys cooperi), Life History Strata 1 mammal (polygamous < 1 yr generation, > 1 litter/yr, 0-40 youngIF/yr, maximum longevity = 5 yr, home range < 1 km2, territorial or colonial). Simulated population initiated in Summer, Year 1 of 3-year population cycle (Table 2). C.V. levels for vital rates (fecundity, subadult survival, adult survival): low C.V. (0.05,0.05,0.05), medium C.V. (0.10,0.15,0.10), high C.V. (0.15, 0.20, 0.15). Populations restricted to habitat patches 1-25 ha (maximum population density = 50 southern bog lemmings/ha). Viable populations «50% probability of extinction in 50 years) indicated by simulations below 0.50 probability of extinction line.
1.0 J I 0.81
0.6
0.4
1 ha ... ----- .. ------------------------------- 2 ha
=: ................................................................................................................................... 3 ha " . ...
---. _. -.-. -_. -... -------------. -. -.. .. ...... --... ----.. - ....... -.-.-.----.- ••• --...... 4 ha
O.2~ , Low c.v. I
O.O~I----~----~,~--~~----~, ----~----~,----~----~I----~----~ o 40 80 120 160 200
1.0~ I .g 0.8 ~ _____ ~ ________________________ ------______ --~4~h~al (J 0 6 .. " ...... :::-----... ----.......... ----------.. --.. --- 5 ha ,... .... ..::;................... ...-------------- -·--6--h--" .... • ........ ............... -.......... _-,... a ... • ..... .. . - ~----------------.-~-~.~-.~--... ~ ... ~ ... ~ ... ~ ... ~ ... ~ ... ~ ... ~ ... ~ ... ~ .... ~.~ ... ~ .. ~ ... ~ ... ~ ... ~ ... ~ ... ~ .... ~ ... ~ ... ~ ... ~ ... ~~ .. ~ ... ~ ... ~ ... ~.~= ... ~ ... ~ .... ~. ~ -- ...... -----~.----.-.-.-.--.-.-.----.-.-.-.--.-.-.-.-Ul 0.4 7 ha I ~ I o 0.2 I .0 Medium C.V. I ~ OO;I-----,-----,Ir-----r-----rl-----.----~I----~----~I----~----~· .- . ~ 0 40 80 120 160 200 .0 o 1.0.-----------------------------------------~! J,...t _
~ 0.8- .... I 0.6-
0.4--
0.2-
.. \:;:........ I .... -.:..... wv 14 h .
--:.1\'-"\&:1\:&.:\::::-:::':-.:,\""", a , ...... - .. ::: ............. _f\r:.... -16 b -"1 .-.--...... :: .... ~ ... ,.. a .• ______ .. _____ · h" .-------
•• " .... ----.. -.,. .. ':::.:-;.·:.::::.::::·········20 a .. ·············. --_._---_.-25 ha
- High c.v. O.O;-----,------r-----~I----~----~----~----~-----I~----,~--~
o 40 80 120 160 200
Initial Population Size
Chi/elli et ale 29
Fig. 3. Simulated probability of extinction for southern bog lemmings (Synaptomys cooperi), Life History Strata 1 mammal (polygamous < 1 yr generation, > 1 litter/yr, 0-40 young/F/yr, maximum longevity = 5 yr, home range < 1 km2, territorial or colonial). Simulated population initiated in Winter, Year 2 of 3-year population cycle (Table 2). C.V. levels for vital rates (fecundity, subadult survival, adult survival): low C.V. (0.05, 0.05, 0.05), medium C.V. (0.10, 0.15, 0.10), high C.V. (0.15,0.20, 0.15). Populations restricted to habitat patches 1-30 ha (maximum population density = 50 southern bog lemmings/ha). Viable populations «50% probability of extinction in 50 years) indicated by simulations below 0.50 probability of extinction line.
1.0.-------------~1~h-a------------------------------~
0.8 :::~.: ........................................................................................................................... . 0.6 ' ..
4-----------.~~~~~------------------------------------------~ .~.- . -~.-------0.4 _.-._.-.--._._.-. __ ..... -.----.-.-._-----_.-._.... 4 -h; 3 ha
. ~ 0.2~ ~ 0.0 I Low C'-Y· i I , , j o 0 40 V"') = 1.0
80 120 160 200
.- - I § 0.8-'13 0.6- ~;:;:;:::::::--____________ 6 ha .5 ~----------------"-"'-"'-"'~"'~"'~'.------------___ .~ ... ~ ... ~ ... -... ~ ... ~ ... ~:-~ ... ~ .. ~~ ... ~ ... ~ ... ~ ... ~.".~ ... ~ ... ~ ... ~ ... ~ ... ~ .. ~ 0.4= 7 ha
~ 0.2-.~ 0.0 - Medium C.V.
I I I I
:-:= 0 40 80 120 160 200 ~ ~ 1.0.-------------------------------------------------~ 8 -~ 0.8- -......... ... -
~ . ............ . .. , .................... .
Initial Population Size
Chi/elli et al. 30
Fig. 4. Simulated probability of extinction for southern bog lemmings (Synaptomys cooperi), Life History Strata 1 mammal (polygamous < 1 yr generation, > 1 litter/yr, 0-40 young/F/yr, maximum longevity = 5 yr, home range < 1 km2, territorial or colonial). Simulated population initiated in Summer, Year 2 of 3-year population cycle (Table 2). C.V. levels for vital rates (fecundity, subadult survival, adult survival): low C.V. (0.05,0.05,0.05), medium C.V. (0.10, 0.15, 0.10), high C.V. (0.15, 0.20, 0.15). Populations restricted to habitat patches 1-30 ha (maximum population density = 50 southern bog lemmings/ha). Viable populations «50% probability of extinction in 50 years) indicated by simulations below 0.50 probability of extinction line.
1.0.-------~----~I~ha----------------------------------1 -
0.8 ". -. .:::~::~ ..... .
0.6-, _________ ~_~~_~~~~~~:~.:~~.~~ .... = ... = .... = ... = .... = ... ~ .... ~ ... ~ .... ~ ... ~ .... ~.~~.~ ... ~ .... = ... = .... ~ ... = .... ~ ... = .... = ... ~.----------.~3=.5~h=a~ -t ..... _ .. ..
~---------------- .. -------------·--·-------~;ih~ 0.4-
~ 0.2- I ~ - Low c.v. ~ 0.0 Iii , : 16' 0 200
o 0 40 80 120 V)
.5 1.0~ I
.§ 0.8 j _______ I j ~:: j+! ---------.::.:.!.! ... -.-. ::.-.::--.. -... -.-... -. .::.=-:.:.:.: ... ::: .. ::-::: ... :::::.:::; ... :::::.:.:.:.:, ... ':-.:::;: ... -.;:; ... ~.-. ::-=-=-.:::.:::::_:::;;;;w....=;,;::::::: .... ~:::::::Iil .. ":w:;;;,, ==:;;;";;:::' .. §.~~.~I
d 0.2~ I
. .e 0.01 Mediu~ c.v. I , I I ! :E 0 40 80 120 160 200 ~
~ 1.0~ ... ~ t:l.. 0.8 ~L_"."""",,, _ •• ___..,.
~~:~--------~_ ~·_ .. ~··_ .. ~··_···-·_·== _____ .. ~ ...... ~ ...... h~a ....... _ ... ~ ...... . ".~ .•....... ,.,.".,. ,.~
30ha-----
0.2~ , +-H~ig~h_C~.V~.~ __ ~ __ ~ ____ ~ ____ .-__ -. ____ ,, ____ .-__ -. ____ ~ 0.0
o 40 80 120 160 200 Initial Population Size
{-
Chi/elli et al. 31
Fig. 5. Simulated probability of extinction for southern bog lemmings (Synaptomys cooperi), Life History Strata 1 mammal (polygamous < 1 yr generation, > 1 litter/yr, 0-40 young/F/yr, maximum longevity = 5 yr, home range < 1 km2, territorial or colonial). Simulated population initiated in Winter, Year 3 of 3-year population cycle (Table 2). C.V. levels for vital rates (fecundity, subadult survival, adult survival): low C.V. (0.05,0.05, 0.05), medium C.V. (0.10,0.15,0.10), high C.V. (0.15, 0.20, 0.15). Populations restricted to habitat patches 1-30 ha (maximum population density = 50 southern bog lemmings/ha). Viable populations «50% probability of extinction in 50 years) indicated by simulations below 0.50 probability of extinction line.
1.0.---------------~1~h-a--------------------------------~ -
~:: = •• ""~o:::::::~:~::::::::::::::::::::::: ..... _ .. _._ .... _ .. _ .................................................... . ~--------------------------~~~------.~~~~~~ ... ~ ... ~ ... ~ ... ~.-----4
3.5 ha ---. -----------_ .. ---_ .. ----------
0.4- 4 ha -
til a 0.2-~ 0 0- Low c.v. o. I
lI') 0 I
40 I
so 120 I
160 200 .5 1.0.,.----------------------------,
e:: -0 O.S-.-...- ~ .. .......
....... ........... ~ -
........ 8 ha
u 0.6-e:: . -
~ 0.4-
.~. ....................•.....................................•................... 7 ha
f.+-I
o 0.2-~ 0.0 - Medium c.v.
I I
160 200 ~ 0 40 80 120 ~ 1.0.,.-----.. -----------------------------. ~ -~ O.S-
0.6-
........ ...,._-_ ....... ................ . .................................... ~ ... = ........... __ -.....cm;;;::::-_25_h_a.....j
····· .... · ...... · .. 30·ha· 4-------~--------------------------------------------------__4
0.4--
0.2-
I
40 I I
80 120 I 0
- High C.V. O. I o 160 200
Initial Population Size
Chi/elli et al. 32
Fig. 6. Simulated probability of extinction for southern bog lemmings (Synaptomys cooperi), Life History Strata 1 mammal (polygamous <1 yr generation, >llitterlyr, 0-40 young!Flyr, maximum longevity = 5 yr, home range < 1 km2, territorial or colonial). Simulated population initiated in Summer, Year 3 of 3-year population cycle (Table 2). C.V. levels for vital rates (fecundity, subadult survival, adult survival): low C.V. (0.05, 0.05, 0.05), medium C.Y. (0.10,0.15,0.10), high c.Y. (0.15, 0.20, 0.15). Populations restricted to habitat patches 3-30 ha (maximum population density = 50 southern bog lemmings/ha). Viable popUlations «50% probability of extinction in 50 years) indicated by simulations below 0.50 probability of extinction line.
1.0~-------------------------------------------.
O 8 ---.. .... """1'I1't! :~--. .~~~~----
0.6= ........ :::=~~~~=:~::=~:::::::::~:::~--::::-: __________ ~_~~_h_ 3.5 ha
~------------------------------~~--------~==~--~~----~ ........................... . ..... , ..... . 0.4- .... ~·4·ha
-
80 I
120
tIJ 0.2-[ 0.0 - Low c.y. o 0
I
40 160 200 ~ 1.0_-.--------------------------------, .-= 0.8-·B 0.6- ................................................. 7 ha = ~-------------------------------------.. -... -... -... -... -... -... -... -.. -... ~ ... ~ .... ~ ... ~ .. = ... = ... ~ .... ~ ... = ... =".= .. ~~ .. ~~ .~ 0.4- 8 ha r.a -~ 0.2-~ - Medium C.Y. ~. 0.0 I I I I I I
:3 0 40 80 120 ~ 1.0.-------------------------------------------------, .g - ~ '- 0.8- ...... ~ ... ~ .... ;:-;; ... ::';';' .... ;-:;; ... = .... =. --......-----..... -..-_n=. I
~ _ '-"'''. .......... 25 ha 1 .t •••••••••••• _ •••••••••••••••••• ;
30 ha .
...................... -.. --~~
I
200 160
0.6-~----------------------------------------------------------~ 0.4--
0.2-_ - High C.Y .
. 0.0 I
o 120 I
160 I
40 I I
80 I
200 Initial Population Size
Chi/elli et al. 33
Fig. 7. Simulated probability of extinction for southern bog lemmings (Synaptomys cooperi), Life History Strata 1 mammal (polygamous < 1 yr generation, > 1 litter/yr, 0-40 young/F/yr, maximum longevity = 5 yr, home range < 1 km2, territorial or colonial). Simulated population initiated in Winter, Years 1, 2, and 3 of 3-year population cycle (Table 2). Initial population size is total released during 3-year translocation program. C.V. levels for vital rates (fecundity, subadult survival, adult survival): low C.V. (0.05, 0.05, 0.05), medium C.V. (0.10,0.15, 0.10), high C.V. (0.15, 0.20,0.15). Populations restricted to habitat patches 3.5-30 ha (maximum population density = 50 southern bog lemmings/ha). Viable populations «50% probability of extinction in 50 years) indicated by simulations below 0.50 probability of extinction line.
1.0~-------------------------------------------' -
0.8-'-0.6-1
----'---'---...:' :::.:::.;~~:::::::::=--------~~ +- ...... ,_...... 3.5 ha
o --, .. -----------------.. ----.. --- ------.4- -.. --.. ---------------4 ha -
~ 0.2-~ 0.0 - Low c.v. o 0 60
I
120 I
J 180
V) = 1.0~--------------------------------------------1 .- -§ 0.8- ~ .~ - ---~--~-
~ 06i ___________________ ~-.. :-.. = .. -=--~-~::~==~~~~====~~~6~h~a .E3 . - ---... -.. ---........ -----------~ 0.4- 7 ha
CO 0.2-c - Medium C.V . . _ O.O+---------~------~--------~r---------r--------~r--------~ ::5 0 60 120 180
C'I:S ~ 1.0~----------------------------------------------.1 o -~ 0.8- I
- .-________ 25 ha,
0.6- 30 ha
0.4--
.0.2-0.0 -, High C.V.
o I I
60 120 Initial Population Size
, 180
(I'J 10-4 ~
~ 0 V)
= .-= 0 .-~ C,,)
= . -Jj ~ 0
.0 .--.-.J::J ~
.J::J 0 10-4 ~
Chile/Ii et ale 34
Fig. 8. Simulated probability of extinction for southern bog lemmings (Synaptomys cooperi), Life History Strata 1 mammal (polygamous < 1 yr generation, > 1 litterlyr, 0-40 youngjFlyr, maximum longevity = 5 yr, home range < 1 km2, territorial or colonial). Simulated population initiated in Summer, Years 1,2, and 3 of 3-year population cycle (Table 2). Initial population size is total released during 3-year translocation program. C.V. levels for vital rates (fecundity, subadult survival, adult survival): low C.V. (0.05, 0.05, 0.05), medium C.V. (0.10,0.15, 0.10), high C.V. (0.15, 0.20, 0.15). Populations restricted to habitat patches 3.5-30 ha (maximum population density = 50 southern-bog lemmings/ha). Viable populations «50% probability of extinction in 50 years) indicated by simulations below 0.50 probability of extinction line.
1.0 -
0.8-- ---0.6- -......... ........ 3.5 ha
0.4--
0.2-- Low c.v.
0.0 0 60
I
120 I
180 1.0
-0.8-
-0.6- ----- ...... ... ~:----
........ -------~-- 6 ha --. -------------------_.---------0.4- 7 ha
-0.2-0.0 - Medium C.V .
0 I I
180 60 120 1.0
-0.8-
-0.6- ._- ... _---------------- 25 ha
.... _- ....... _-0.4- 30 ha
-.0,,2-o - High C.V .
. 0 I
0 60 120 180 Initial Population Size
Q) N .-en ~ 0 .-~ ~ -::s
Chi/elli et al. 35
Fig. 9. Mean population size of simulated viable «50% probability of extinction in 50 years) populations of southern bog lemmings (Synaptomys coopen), Life History Strata 1 mammal (polygamous, < 1 yr generation, > 1 Iitterlyr, 0-40 young/Flyr, maximum longevity = 5 yr, home range < 1 km2, territorial or colonial). C.V. levels for vital rates (Table 2) (fecundity, subadult survival, adult survival): low C.V. (0.05, 0.05, 0.05), medium C.V. (0.10,0.15,0.10), high C.V. (0.15, 0.20, 0.15). Populations restricted to habitat patches 4-8 ha (maximum population density = 50 southern bog lemmingslha). A: 60 southern bog lemmings released in Summer, Year 1 into 4 ha habitat patch, low C.V. B: 80 southern bog lemmings released in Winter, Year 2 into 4 ha habitat patch, low C.V. C: 180 southern bog lemmings released in Summer, Year 3 into 8 ha habitat patch, medium C.V.
180
140
100
60 A
~" \ i 4-
0 10 20 30 40
180
140 +
g- 100 ~ V"J ~ B ~ 60 Q)
~ 0 10 30 40 20 280 240 200 160 ·120
80 0 10 20 30 40
Simulation Year
50
50
50
~ ~
o V)
= .-= o .-..... ()
= .-.~ ~ ~ o ~ .-.-~ ..0 8 ~
Chi/elli et ale 36
Fig. to. Simulated probability of extinction for fishers (Martes pennantz), Life History Strata 2 mammal (polygamous, 1-2 yr generation, 1litter/yr, O-to young/F/yr, maximum longevity = 15 yr, home range = 1-100 km2, territorial - intrasexually exclusive). Populations simulated with mortality during trapping season: juv = 0.25, ad M = 0.17, ad F = 0.08. Other vital rates as listed in Table 2. Variability (C.V.) on home ranges (HRV) = 0.05-0.20. Variablity (C.V.) for vital rates (fecundity, juvenile survival, adult survival): low C.V. (0.05, 0.10, 0.05), medium C.V. (0.10, 0.15, 0.10), high C.V. (0.15,0.20, 0.15). Populations restricted to habitat patches = 235 km2. Viable populations «50% probability of extinction in 50 years) indicated by simulations below 0.50 probability of extinction line.
1.0~-------------------------------------------'
0.8 ~~~, i ---~ HRV = 0.201
0.6 ~~- --~.:.---=:.------------ ---------------------------------- ----------J 0.4-1 HRV = 0.05 i
O.2~ Low c. v. I 0.0+0---..------,..210---....-----40.-' ------.-------1
60
1.0~------------------------------------------~
0.8-- HRV = 0.05
0.6-~------------------------------------------------------------~
0.4--
0.2-- Medium C. V.
O.O+-------~----~------~------~------~----~ o 20 40 60
Initial Population Size
Chi/elli et al. 37
Fig. 11. Simulated probability of extinction for fishers (Martes pennantz), Life History Strata 2 mammal (polygamous, 1-2 yr generation, 1liuerlyr, 0-10 young/Flyr, maximum longevity = 15 yr, home range = 1-100 km2, territorial - intrasexually exclusive). Populations simulated with mortality during trapping season: juv = 0.22, ad M = 0.15, ad F = 0.07. Other vital rates as listed in Table 2. Variability (C.V.) on home ranges (HRV) = 0.05-0.70. Variablity (C.V.) for vital rates (fecundity, juvenile survival, adult survival): low C.V. (0.05, 0.10, 0.05), medium C.V. (0.10, 0.15, 0.10), high C.V. (0.15, 0.20, 0.15). Populations restricted to habitat patches = 235 km2. Viable populations «50% probability of extinction in 50 years) indicated by simulations below 0.50 probability of extinction line.
1.0~------------------------------------------~
0.8- -............. .. 0.6 - ::::......... .-...... HRV - 070 ....... --._-....... _._.-...... - . --- -... ......... . ..... -._- --+------~ ----~ .. -~··~···~~-HRV = 040 -.-.-------------- .. ------------
............. ; ...... :::.::::::.:::: ................. -: .............................. ·············H····R .. ·V·· .. ·:···0-·2 .. 0 .. ··· .. ··· .. ········ ...... . ().~- ~ ---._-------------------------- -. .------------
-
-O AAV=~ ~ .2-
~
~ 0.0 Low c.v. ~ 0
I
20 40 60 = 1.0~--------------------------------------------~ .-§ ().8 - :::::::::-. ____ _
.+: 0 6- :::::;.:::~ .. :~:~----------.-----.-----------.---.-- .. ----------------~-~~-~~?~-.~ . -t---------.. --...... --~ .. _ .... ~ .. ·~ .. ~ .. ·~· .. s·H~·R~·V~-~0~.20~··=·-~·· .. ~···~ .... ~···~ .... = ... =H=R~V~.=~.=0.=4O~~~~ ... ~ ... ~ .... ~ ... ~ ... ~ .... ~ ... ~ .. . .- ----------------------- ---------------------Uj O.~= ~ 0.2-C 0.0
- Medium C. V. .-.-.D ~
.D o ~
~
0
1.0~ 0.8
0.6-
O.~-..
0.2-- High C.V
0.0 . 0
I I I
20 40
-------------
I
20 40 Initial Population Size
AAV = 0.05
60
HRV = 0.05
60
Chi/elIi et al. 38
Fig. 12. Simulated probability of extinction for fishers (Martes pennantl), Life History Strata 2 mammal (polygamous, 1-2 yr generation, 1 litterlyr, 0-10 young/Flyr, maximum longevity = 15 yr, home range = 1-100 km2, territorial - intrasexually exclusive). Populations simulated with mortality during trapping season: juv = 0.16, ad M = 0.11, ad F = 0.05. Other vital rates as listed in Table 2. Variability (C.V.) on home ranges (HRV) = 0.05-0.70. Variablity (C.V.) for vital rates (fecundity, juvenile survival, adult survival): low C.V. (0.05,0.10,0.05), medium C.V. (0.10, 0.15, 0.10), high C.V. (0.15, 0.20, 0.15). Populations restricted to habitat patches = 235 km2. Viable populations «50% probability of extinction in 50 years) indicated by simul,ations below 0.50 probability of extinction line.
1.0.-----------------------------------------~ -
0.8--
O.S-~----------------------------------------------------------~
..........
.......... :............ HRV - 070 .. ...... .... .. _-- - . ......... ::::......... ----._--- .. _-------------------_. -- - ----_._------------------...... ......................... . ·-········· ........................... HRV = 04ON .••..............•• ····•·•·••· ---- HRV = 0.20. ______ .. ______________________ · __________________ _
0.4--
~ 0.2-HRV = 0.05
I I I I t 0.0 - Low C.V.
V1 0 20 40 SO .5 1.0-,-------------------------, = .2 0.8-
-
t)
= .- -0.6-
~ 0.4- HRV = 0.20~··::::::~:: .. ·...... HRV = 0.70 . ~~---....... .. .. -~-.- .. -- ----------
... ~ !IIII ••••••• ---""---_..' --------------------------------
~-"·································-····HRV = 040 ...................... -............................. . ~~---==~----- .. ---------------~-~~:::~------------------------_.-
HRV = 0.05
SO
-...... HRV = 0.20
I I I . I
20 40 60
Initial Population Size
Chilelli et al. 39
Fig. 13. Simulated probability of extinction for fishers (Martes pennantz). Life History Strata 2 mammal (polygamous, 1-2 yr generation, llitterlyr, 0-10 young/Flyr, maximum longevity = 15 yr, home range = 1-100 km2, territorial - intrasexually exclusive). Populations simulated with no trapping mortality, nontrapping mortality M = 0.75 F. Other vital rates as listed in Table 2. Variability (C.V.) on home ranges (HRV) = 0.05-0.70. Variablity (C.V.) for vital rates (fecundity, juvenile survival, adult survival): low C.V. (0.05,0.10, 0.05), medium C.V. (0.10, 0.15, 0.10), high C.V. (0.15, 0.20, 0.15). Populations restricted to habitat patches = 235 km2. Viable populations «50% probability of extinction in 50 years) indicated by simulations below 0.50 probability of extinction line.
1.0~-----------------------------------------' -
... -... -HRV = 0.20i4;;: .. :~"'-"·"_,, HRV - 070 ~!'1110 '" ....... _
~~ .... ,... -..... -.-.-._---------------_._-----_._------------------------.'._-VJ 0.2-~ -~ 00 LowC.V. ~ . o 0
~~~ ....... HRV = 0.40 .. _ ............... · .... · ...... · .............. · .... ··· ............ _· .. · .. · ........ · ............ .. ~~~----------------------------------------------- ,-------_._-----HRV 0.05
20 40 60 ~ 1.0~---------------------------------------------, d .-d o
0.8-
'B 0.6- ........ d +-~~~~~~~----------------------------~--------~ .~>< 0.4- HRV = 0.20~· .. ···· .......... ..
I
..- -.. .... .... HRV 070 ~~ .. ..... ,... -._._--._.-.. -._. = . rT' - '-.......... ······ .. ···HRV - 040---·_·_-------_·_------·_·_---------------_·_·_--~ --- .. ".... - . . ............................................................... -............................ .. ~ 0.2- ~ ----------------------------------------- -- -----------~--o - M d' HRV = 0.05 ~ 0 0 e tum C.V. ~ • I
:.::: 0 .-.,J::J ~ 1.0~--------------------------------------------~ .,J::J
20 40 60
o ~ 0.8-
- ....... 0.6- HRV - 020·· .. ··~ .. • .. -- . -"- ...... ....... HRV = 0.70
0.4-i---------~~~-~ .... ~~~···~··~~-.. ~~:~~·;~;~~ .. ·-.. ·~ .. ·-.. ·-... ~ .. H~R~V~-~0~4~0~~ ... ·~-~--~-~--~-~·-~·-~·~-~·-~·-~:~:.~~~:~~.~~~.~~~~~~-.3~"A~R~A_~._ -~-------------------;--~~~~~~~~~~~~~~~~~~~:~~::----------------. - HRV 0.05
0.2-High C.V.
O.O-t----r---r-----.-----r-----r-------l o 20 40 60 Initial Population Size
Chi/elli et al. 40
Fig. 14. Simulated probability of extinction for fishers (Martes pennantl), Life History Strata 2 mammal (polygamous, 1-2 yr generation, 1 litter/yr, 0-10 young/F/yr, maximum longevity = 15 yr, home range = 1-100 km2, territorial - intrasexually exclusive). Populations simulated with no trapping mortality. Other vital rates as listed in Table 2. Variability (C.V.) on home ranges (HRV) = 0.05-0.70. Variablity (C.V.) for vital rates (fecundity, juvenile survival, adult survival): low C.V. (0.05,0.10, 0.05), medium C.V. (0.10, 0.15
2 0.10), high C.V. (0.15,0.20,0.15).
Populations restricted to habitat patches = 235 km • Viable populations «50% probability of extinction in 50 years) indicated by simulations below 0.50 probability of extinction line.
1.0~-Lo--w-C-.V-.. ------------------------~----------------~
O.B
0.6-4-----------------------------------------------------------~ 0.4--
~ 0.2 HRV = 0.40 ~ HRV = 0.20!!!t!r t~.. HRV = 0.70 ~ 0.0~~HR~V~~Q~0~5;==n~~·-~···~·~--~-~--m----m-------~-~-~-~-~~I~~~~~I~~~~~~~~~~·-~
~ 0 20 40 = 1.0 1M d' CV ._ e lum ..
§ 0.8-.- -..... U
= 0.6-.-..... ~ 0.4-
-c.a 0.2- HRV = 0.20
- HRV 0.40:;:;:---·"--",_",~ & 0.0 HRV 0.05
:.c 0 ~ 1.0 _ High c.v. ~ O.B-
0.6-
20 40
60
60
+-----------------------------------------------------~ 0.4-
-0.2-
HRV = 0.201:'____ HRV 070 HRV = 040 .... .::; .. --- .. -... = . . w~~w~~~~:~::::::::~::::::~:::~~~~~~~nAftAft~ftA~~~~~~~!-·-.-.:::~~:.~~~~~~~:
·0.0-+-________ ,,~H~R~V~=~O,~05~-------------------------,--_-_--_-_--_-____ ~--------~I------~
o 20 40 60 Initial Population Size
Chi/elli et al. 41
Fig. 15. Simulated probability of extinction for black bears (Ursus americanus), Life History Strata 3 mammal (polygamous, >2 yr generation, <1 litter/yr, 0-6 young/Flyr, maximum longevity = 30 yr, home range = 5-600 km2, intrasexual overlap in home ranges). Populations simulated with i survival « 1-year-old, > 1-year old): M = (0040,0.60), F = (0.80,0.90); i litter size = 2.3 (range = 1-4); breeding rates as reported by Elowe and Dodge (1989) and Elowe et al. (1991) (Table 4). Variablity (C.V.) for vital rates (fecundity, juvenile survival, adult survival): low C.V. (0.05, 0.10, 0.05), medium C.V. (0.10, 0.15, 0.10), high C.V. (0.15, 0.20, 0.15). Populations restricted to habitat patches = 250 km2 (maximum population densities restricted to 0.15-0.45 bears/km2). Viable populations «50% probability of extinction in 50 years) indicated by simulations below 0.50 probability of extinction line.
1.0~------------------------------------------~! - I
0.8- _____ ._._._. ___ ._.- max. density = 0.15 bears/km2 I -
0.6-~----------------------------------------------------------------~ 0.4--
0.2-0.0- Low C.V.
o
............................................................................. 0.25 bears/km2
.... -... --- ----------_____ 0.35 bears/km2
--------------------------------------. 0.45 bears/km2 I I I I I
20 40 60 80 100 1.0~----------------~-------------------------.
-r:: 0.8- -.-.-.-._-_.-._.--- max. density = 0.15 bears/km2 o .-.., u r::
-0.6-
.- 0 .., ~4- ->< ........................ 0 25 be /km2 III - .. -.... ................................................... ars
f+-; 0.2- ~ .. -.. _ .. _ 0.35 bears/km2
O.+--..:M::e:::d:::iu~m~C:::. V~ • .,.--__ ...,.-_-_-=::-=--=-=--=--=-::;:--= .. =--=--=-=--:;:-=--=-=--=--=-:::;:--=--=-=--=-=--:;:' ==0=o4=5=be~ars=/km=~2 .e-- 0.0 I a 0 20 40 60 80 100 ~ 1 n~I-----------------------------------------------------'li .:c .. ..,~ I
£ 0.8j --.. --·-·-· .. ·---._ ... max. density = 0.15 bears/km2 I O.6~ I 04 .............. I
• -----~ ...................... /km2 I . 0.2 -.... --::- .......... · .......... · .............. · .. · .. 0.25 bears
~H~igh~C:..V;..:.~_-r-_ .. ~ __ .--~_-!:.._~_7-=.-.. :;:-=--=--=-=--=--;::--=-=-_= __ = __ :;:_= __ = .. _=~3=_?=_!>e;: __ =~~=fkm= __ =_~~. ==0=o4=5=br=ea=rs=/km~21 0.0 ' o 20 40 60 80 100
Initial Population Size
Chi/elli et ale 42
Fig. 16. Simulated probability of extinction for black bears (Ursus americanus), Life History Strata 3 mammal (polygamous, > 2 yr generation, < 1 Iitterlyr, 0-6 young/F/yr, maximum longevity = 30 yr, home range = 5-600 km2, iritrasexual overlap in home ranges). Populations simulated with x survival «l-year-old, ~l-year old): M = (0.36,0.54), F = (0.80,0.90); x litter size = 2.3 (range = 1-4); breeding rates as reported by Elowe and Dodge (1989) and Elowe et al. (1991) (Table 4). Variablity (C.V.) for vital rates (fecundity, juvenile survival, adult survival): low C.V. (0.05,0.10,0.05), medium C.V. (0.10,0.15,0.10), high C.V. (0.15,0.20,0.15). Populations restricted to habitat patches = 250 km2 (maximum population densities restricted to 0.15-0.45 bears/km2). Viable populations «50% probability of extinction in 50 years) indicated by simulations below 0.50 probability of extinction line.
1.0~ 0.8
0.6
0.4
~ 0.2
~ 00: Low C.V. ~ • -1 I
~ 0
---------.-.-.----- max. density = 0.15 bears/km2
............................ 2 ................................................. 0.25 bears/km
-. -- ........... '. -.. ~- -...... 2 ---_.. .. .... -------_______ _ ____ -------·0.35 bears/km -- --._--_ ... -----'-00_ 0.45 bears/km2 I
I I I I I I
20 40 60 80 100
.5 1.0_~-------------------·--·---·--·--·------·--m-ax.--d-e-ns-i-ty-=--~-15--be-a-rs-Ikm--2----------------'
§ 0.8-.- -t) 0.6-.5 ~----------~.~-.---------------------------------------------~ ~ ......... """ ........ .. r~ 0.4- ~~-... ~ ... -.-.. 2 JooI-4 _ -......... • .. ----______ _ _________ --. 0.35 bearslkm CO 0.2- ......... ---------------- 0.45 bearslkm2
............................. 2 ................................................ 0.25 bearslkm
0.0 - Medium C.V.
o 20 i
40 I
60 80 100 1.0!Ji---------------------------------2----------~
-.-.-------------.- max. density = 0.15 bears/km
0.8
O 6 .......................... 025 bea /km2 ........ . ............................. ,..................... . rs . -.......
~----------~~~~----------------------------------------~ 0.4 ~:.............. 2 I .......... -------- 035 be rs/km
° 0.2 .~'.'.____=_==_--_--_--_-_--_--_--_--_--_--_-._. __ a __ ~
High C. V. 0.45 bears/km2 O.OT---~--~----~--~--~----~--~--~--~~~
o 20 40 60 80 100 Initial Population Size
Chi/elli et alo 43
Fig. 17. Simulated probability of extinction for black bears (Ursus americanus), Life History Strata 3 mammal (polygamous, >2 yr generation, <1 litterlyr, 0-6 youngIFlyr, maximum longevity = 30 yr, home range = 5-600 km2, intrasexual overlap in home ranges). Populations simulated with x survival « 1-year-old, > I-year old): M = (0.32,0.48), F = (0.80,0.90); x litter size = 2.3 (range = 1-4); breeding rates as reported by Elowe and Dodge (1989) and Elowe et al. (1991) (Table 4). Variablity (C.V.) for vital rates (fecundity, juvenile survival, adult survival): low C.V. (0.05, 0.10, 0.05), medium C.V. (0.10,0.15, 0.10), high C.V. (0.15, 0.20, 0.15). Populations restricted to habitat patches = 250 km2 (maximum population densities restricted to 0.35~Q.45 bears!km2). Viable populations «50% probability of extinction in 50 years) indicated by~' -simulations below 0.50 probability of extinction line. .
1.0.-----------------------------------------~ -
0.8- --__ ..
06- ~-- .. -- .......... ............. ------ .-----. ~~ ._---.. _---- .. _---------------
1-------------------~~ __ ~,--------------~----------------------~ 0.4- '-------__ _ - ----------------------------~
max. density = 0.35 bears/km2
~ 0.2- 0.45 bears/km2
~ 0 0- Low CoV. ~ • I I I 1
o 0 20 40 60 80 100 ~ ~--------------------------------------------------~ c:: 1.0 .- -a 0.8 - ............... --....... max. density = 0.35 bears!km2 ...... -i .............. -...,. -.....
- 0.45 bears/km2 CO 0.2-~ 0.0 - Medium CoV'
r I I T r I I i
:E 0 20 40 60 80 100 ~ 1.0~~i----------------------------------------------~1
O 8 -...... -.. max. density = 0.35 bears!km2 jl... • ---- - .............. ..
- ~ --... -----_. ------ .... _-------------------------------0.6-+-______ ------_-=::::--~~============::j 004- 0.45 bears/km2
t -
0.2-~-HJ~·g~h~C=.~V~.--~----~----~----r_--_.----,_----._---.----~
0.0 0 20 I 40 601
80 100 Initial Population Size
Chi/elli et al. 44
Fig. 18. Simulated probability of extinction for black bears (Ursus americanus), Life History Strata 3 mammal (polygamous, >2 yr generation, <1 litterlyr, 0-6 young/Flyr, maximum longevity = 30 yr, home range = 5-600 km2, intrasexual overlap in home ranges). Populations simulated with x survival «I-year-old, .2=.1-year old): M = (0.40,0.60), F = (0.76,0.86); x litter size = 2.3 (range = 1-4); breeding rates as reported by EIowe and Dodge (1989) and Elowe et at. (1991) . (Table 4). Variablity (C.V.) for vital rates (fecundity, juvenile survival, adult survival): low C.V. (0.05, 0.10, 0.05), medium C.V. (0.10,0.15, 0.10), high C.V. (0.15,0.20,0.15). Populations restricted to habitat patches = 250 km2 (maximum population densities restricted to 0.15-0.45 bears/km2). Viable populations «50% probability of extinction in 50 years) indicated by simulations below 0.50 probability of extinction line.
1.0~--------------------------------------1 -
0.8--
0.6-+---------------------------------~------------I 0.4- --.---.-.---------- max. density = 0.15 bears/km2
-~ 0.2-~ - Low c.v.
o 0.0 V) 0
.......................... 0.25 bears/km2 2 ................................................... 0.35 bearslkm 0.45 bears/km2
I I I I I I
20 40 60 80 100 .S 1.0..,.-------------------------,
-§ 0.8-.-o -= 0.6-.- ~-------------~--~-~--~-~--~--~~------------------~----------------~ Jl 0.4- --- max. "density = 0.15 bears/km2
ro 0.2-~ 0.0 - Medium C.V. I
~ 0 20 ~ 1.0.-----------------------------------------------~ .... -
~
..... ;: .. ::;:;:........ 0.25 bears/km2 2 .... ..::::......................................... 0.35 bears/km
... _--- 0.45 bears/km2 I
40 I
60 I I
80 I
100
~ 0.8--
0.6- ----------.-----___ max. density = 0.15 bears/km2
~--------------------------------------------------------------------------~ 0.4- ~ ....... . - - """-~ ........ .
. 0.2- -~~......... 0.25 bears/km2 .~:............................................. 0.35 bears/km2
-I_~~·g~~s~~ __ ~----~---~~:--:-:--~.-~-~-====~=====¥~~~~O:.4:5~b~ea~r~s~~2~ 0.0" -t .. I I - I--------.. ~--------~---------· I
o 20 40 60 80 1 00 Initial Population Size
Chi/elli et al. 45
Fig. 19. Simulated probability of extinction for black bears (Ursus americanus), Life History Strata 3 mammal (polygamous, >2 yr generation, < 1 litter/yr, 0-6 young/Flyr, maximum longevity = 30 yr, home range = 5-600 km2, intrasexual overlap in home ranges). Populations simulated with x survival «l-year-old, ~l-year old): M = (0.40,0.60), F = (0.76,0.86); x litter size = 2.07 (range = 1-4); breeding rates as reported by Elowe and Dodge (1989) and Elowe et at. (1991) (Table 4). Variablity (C.V.) for vital rates (fecundity, juvenile survival, adult survival): low C.V. (0.05,0.10,0.05), medium C.V. (0.10,0.15,0.10), high C.V. (0.15,0.20,0.15). Populations restricted to habitat patches = 250 km2 (maximum population densities restricted to 0.15-0.45 bears/km2). Viable populations «50% probability of extinction in 50 years) indicated by simulations below 0.50 probability of extinction line.
1.0~-------------------------------------------. -
O.s--
0.6-
0.4--
~ 0.2-~ 0.0 - Low c.v.
o 0 V') = 1.0 .- -= O.So .- -
------•• --.-.-••• maL density = 0.15 bears/km2
~ .. __ .?~ .. ~~.z.. 035 bears/km2 0.45 bears/km2 I I I I I
20 40 60 SO 100
o 0.6-~ O.4-~------------·-----·--~·~-·~·~--.-~·---m-aL--d-e-m-ity--=--0-.1-5-b-e-ars--/km--2----------------~ lo0\o004 ~
b 0.2-.€ 0.0 - Medium c.v. := 0 20
....................... 0.25 bears/km2 ". /km2 ....................................... 0.35 bears 0.45 bears/km2
I I I I
40 60 so 100 .D ~ 1.0.------------------------------------------------.
.D -8 O.S~ -
0.6-
0.4--
·0.2-0.0 - High c.~.
o
-._---•••• __ ._--••• maL demity = 0.15 bears/km2
~~........ 0.25 bears/km2 ,....................................... 035 b /km2 .. ~------.- ___ .___ . ears
--------------------.- 0.45 bears/km2
I I I I I
20 40 60 80 100 Initial Population Size
Chi/elli et al. 46
Fig. 20. Simulated probability of extinction for black bears (Ursus americanus), Life History Strata 3 mammal (polygamous, > 2 yr generation, < 1 IiUer/yr, 0-6 young/F/yr, maximum longevity = 30 yr, home range = 5-600 km2, intrasexualoverlap in home ranges). Populations simulated with x survival « 1-year-old, > I-year old): M = (0.40,0.60), F = (0.76,0.86); x litter size = 2.00 (range = 1-4); breeding rates as reported by Elowe and Dodge (1989) and Elowe et al. (1991) (Table 4). Variablity (C. V.) for vital rates (fecundity, juvenile survival, adult survival): low C.V. (0.05,0.10,0.05), medium C.V. (0.10,0.15,0.10), high C.V. (0.15,0.20,0.15). Populations restricted to habitat patches = 250 km2 (maximum population densities restricted to 0.15-0.45 bears/km2). Viable populations «50% probability of extinction in 50 years) indicated by simulations below 0.50 probability of extinction line.
1.0~------------------------------------------~ -
O.s--
0.6-
0.45 bears/km2 0.2-
~ 0.0 -Low c.;. ~ 0
o ~ 1.0l .~ O.s~ o '-5 0.6 ........ -.. -......... __ max. density = 0.15 bears/km2
= +-------------------~~--------~------------------------~ .~ 0.4 ~;;.;;". II
~ ... ~ ... c.o 0.2 M . ~..... 0.25 bears/km
2 0.35 bears/km2 21 o 0.0 edIUm~C::::.:...:V...:.. -jr------,r----.~~~~.::::::::::.:~::~:.::; ... = ... = ... = .... :::::"'::::::"'=;"'=~ ~ ......... _.,.! _0_.4_5_b-:-ea_rs_/km __ -,:
~ 0 20 40 60 80 1 00
~------------~~--------------------------~--------------~ 0.4- ............ _ ......... max. density = 0.15 bears/km2 .... ~~ ......
~~I\" ~ ... - 2
~.~~-~ ......... ~:~ .. ?~~~~... 0.35 bears/km2 I
20 I I
40 60 80 100
~ 1.0-r,-----------------------, .!:J -
8 0.8-~ -
0.6---------.- ... -.. .. 2
-'-'- max. densIty = 0.15 bears/km
0.4--
·0.2-0.0 - High C.V.
o
~--------~··~----------------------------------------4 .... ,-......:.:. .... , ... ,~ ... ". .
.... ~....... 2 ...... ~~....... 0.25 bears/km
.... ~~:::................................. 0.35 bears/km2
--------------------~----. 0.45 bears/km2
. 20
• I I
40 60 I
100 so Initial Population Size
Chi/elli et al. 47
Fig. 21. Simulated probability of extinction for black bears (Ursus americanus), Life History Strata 3 mammal (polygamous, >2 yr generation, < 1 Iitter/yr, 0-6 youngjF/yr, maximum longevity = 30 yr, home range = 5-600 km2, intrasexual overlap in home ranges). Populations simulated with x survival «l-year-old, 2.1-year old): M = (0.40,0.60), F = (0.72,0.81); x litter size = 2.3 (range = 1-4); breeding rates as reported by Elowe and Dodge (1989) and Elowe et at. (1991) (Table 4). Variablity (C.V.) for vital rates (fecundity, juvenile survival, adult survival): low C.V. (0.05,0.10,0.05), medium C.V. (0.10t 0.15,0.10). high C.V. (0.15,0.20,0.15). Populations restricted to habitat patches = 250 km2 (maximum population densities restricted to 0.15-0.45 bearsIkrn2). Viable populations «50% probability of extinction in 50 years) indicated by simulations below 0.50 probability of extinction line.
1.0~----------------------------------------1 -
0.8--
0.6 - ~"~ .. ~ .. , ~-----------~-'~'~~"~'~----------------------------------------~
0.4: ,~ •.• max. density = 0.15 bearslkm2
0.2 - ~~~~__ 0.25 bearslkrn2 2 2 ~ - Low C.V. -- 0.35 bearslkrn 0.45 bearslkrn ~ 0.0 >. 0
I I
20 ~ 1.0i .5 0.8j ~ ~~~."."."
I I
40 I I I I I
60 80 100
'';:: 0.6 - ,,~~~\:.. .......... max. density = 0.15 bearslkrn2 U 4-------------~~--~~~~~~~~~~~-----------------~ d '.-~!t;, ·....0.4- '"'-~~Io ~ ~ 2 x - -.'~~!o 0.25 bears/km rT"I 0.2- .~:':""""'"'''''' ....... . ............ . '0 - Medium C.V. ... .... _- 0.35 ~~~~2 0.45 bears/km2
~ 0.0 ..... 0 -~ 1.0~ o O.8~ $-4 -i ~ 0.6
0.4
.0-.2 0.0 . High C.~.
o
I I I I
20 40 60 80 100
~.---.-~ 2 '" ".-.- d' 015 b Ikrn ~'" --._-- max. enslty =. ears ~ ... " ... , .......
~~ 2 ". ............... 0.25 bearslkrn ........ ::::::::::::::::::::::. 0.35 bears/km2
...... ---------___ .. __ . 0.45 bears/km2
------------------~
20 40 60 80 100 Initial Population Size
= o .-t) = . -~ ~ o C .-.-~ .D o ;.... ~
Chi/elli et al. 48
Fig. 22. Simulated probability of extinction for black bears (Ursus americanus), Life History Strata 3 mammal (polygamous, >2 yr generation, <1 litterlyr, 0-6 youngIFlyr, maximum longevity = 30 yr, home range = 5-600 km2, intrasexual overlap in home ranges). Populations simulated with x survival «I-year-old, > I-year old): M = (0.40,0.60), F = (0.80,0.90); x litter size = 2.3 (range = 1-4); breeding rates as reported by Elowe and Dodge (1989) and Elowe et aI. (1991) (Table 4). Variablity (C.V.) for vital rates (fecundity, juvenile survival, adult survival): medium C.V. (0.10,0.15,0.10). Initial population size is total released during 1,2, or 4-year translocation profram, ?:,~5% adult f~males r~l~ased ~th cubs. Populations restricted to ~abitat patch~s = 250 km (maxtmum--populatIon densItIes restrIcted to 0.25 or 0.45 bears/km2). Viable populations «50% probability of extinction in 50 years) indicated by simulations below 0.50 probability of . extinction line.
1.0 J 1 year Program
0.81 0.6 max. density = 0.25 bears/km2
~::~ max densi~ = Q45 be~:::::::'::':::'I~F:;;;~=E;~:!' -f ~ I
O 0 I 15% ad F released with cu.;;---------.. -...... :U I
• I I I I r r I o ~ ~ 00 00 1.0~,----------------------------------------i
- 2 year Program 0.8-
:
0.6 - max. density = 0.25 bears/km2
0.4- ................. I\ .. I\r-:::.I'::',~~.~~ F released with cubs . ..-------.. ... - ................ ••·· .. ··::::.::.:.:::.:::.=.r.ftAft"" ..... A _____ "' .. ""V ......... • .. ., .. --
max. densit = 045 be .. ;................ 15% ad F released with cubs . _ y. ars/km 15% ad F released WIth cubs 1-______ ~--~O~~~o~aedlF~r~e~le~as~e~d~w~ith~cu~b~s~:::::::::-~-~ .. ~ .. -~-~--~ .. ~-;-~-~;;~~;;~~
0.2-
0.0 I ! I ! I I I
o 20 ~ 60 80 10~1------------------------------------~
· ~ 4 year Program
0.8~ -l
0.6 J max. density = 0.25 bears/km2
0-4 1'::\:0;" .. "............ 15% ad F released with cubs . . l ........ " .. ~...... .. ... ____ ...... "".w .. " .. , ~ -... ':,:··· .. ·················v .. v ....... _____ ... " ..... " .. A ......... --s ..... _._ ••••• -
O 2 I. . 0% ad F released with cubs · l max. densIty = 0.45 bears/km2 0% ad F released with cubs
. 0.0 : 15% ad F released with cubs -
o 20 ~ 60 80 Initial Population Size
Chi/elli et al. 49
Fig. 23. Simulated probability of extinction for black bears (Ursus americanus), Life History Strata 3 mammal (polygamous, > 2 yr generation, < 1 litterlyr, 0-6 young/Flyr, maximum longevity = 30 yr, home range = 5-600 km2, intrasexual overlap in home ranges). Populations simulated with x survival « 1-year-old, > I-year old): M = (0.40,0.60), F = (0.76,0.86); x litter size = 2.3 (range = 1-4); breeding rates as reported by Elowe and Dodge (1989) and Elowe et al. (1991) (Table 4). Variablity (C.V.) for vital rates (fecundity, juvenile survival, adult survival): medium C.V. (0.10, 0.15, 0.10). Initial population size is total released during 1,2, or 4-year translocation profram, 0-15% adult females released with cubs. Populations restricted to habitat patches = 250 krn (maximum population densities restricted to 0.25 or 0.45 bears/km2). Viable populations «50% probability of extinction in SO years) indicated by simulations below0:50~probabilityof extinction line.
1.0 1 - year Program 0.8-
0.6 - max. density = 0.25 bears/km2
0.4- 15~~~~ .. ~ released with cubs - .-~~~~.,.,
~ 0.2 - max. density = 0.45 bears/km2 .~~::~~"............. 0% ad F released with cubs ~ - 0% ad F released With cubs ~~"'~"""""""IUlft::'::::'::::'::~:::'M-:~::::'::::'"::'""""""''''''''''-''-''->. 0.0 I 15% ad Freleased with cubs I I I
o 20 40 60 80 o \(') = 1 0...,...,--------------------------, '.-4 • 2 year Program
§ 0.8 ,.-4 ~
g 0.6 max. density = 0.25 bears/km2 ,.-4
rE O.4j 0% ad F~~.~tb cubs
C,j..f 0 2 m d 'ty 045 be 2 ~"'" -.. o . -: ax. ens) 0% ad F r:~~ ~th.::.:··~:b·:O:""............ 15% ad F released with cubs g 0.0 1 15% l!d,F rele~~ ~~h scubs ........................................ uv .. '7vu" .. " .. " .... wv
n--------- ,
~ 0 ~ 40 00 00 ~
.J::J e ~
1.0 ~ 4 year Program 0.8
0.6 max. density = 0.25 bears/km2
15% ad F released with cubs ::;.:.:. ...... .
I ----- ••••
0,.4
0.2 max. density = 0.45 bears/km2 ~". 0% ad F released with cubs ~.... 0% ad F released with cubs, 159& ad Freleased ~th cubs ~ _______________________ • __ • _______ ~_A __ RA~A"ARftftA
0.0 -+----".-- - I I
o 20 60 80 Initial Population Size
Chi/elli et al. 50
Fig. 24. Simulated probability of extinction for black bears (Ursus americanus), Life History Strata 3 mammal (polygamous, >2 yr generation, <1 Iitterlyr, 0-6 youngIFlyr, maximum longevity = 30 yr, home range = 5-600 km2, intrasexual overlap in home ranges). Populations simulated with x survival « l-year-old, > I-year old): M = (0.40,0.60), F = (0.76,0.86); x litter size = 2.0 (range = 1-4); breeding rates as reported by EJowe and Dodge (1989) and Elowe et a1. (1991) (Table 4). Variablity (C.V.) for vital rates (fecundity, juvenile survival, adult survival): medium C.V. (0.10,0.15,0.10). Initial population size is·total released during 1,2, or 4-year translocation pro:¥ram, 0-15% adult females released with cubs. Populations restricted to habitat patches = 250 'km (maximum population densities restricted to 0.25 or 0.45 bears/km2). Viable populations
·N_'""'""·~"' __ "__ «50%' probabilIty ofextincrionin'SO-ye-a-tstrrnlicated·by'simutations beiow 6.50 probability of'------. extinction line.
1.0 P - 1 year rogram
O.B 0.6 - max. density = 0.25 bears/km2
0.4- ,_ - 2~"''''-
O 2- max. densitv = 0.45 bearslkm ~~hP% ad F released with cubs • 0% ad F released with cubs ~-~...... . 15% ad F released with cubs
- 15% ad Freleased with cubs .A.-~Aftft.ft.~ft,"r.~"~"~~~~~:.~~~~~~~"~~r."~nr."~nft.ft"ft
0.0 o
I I I
20 I I
40 60 BO 1.0~------------------------------------------~
- 2 year Program
= O.B-o -.-o 0.6 - max. density = 0.25 bears/km2
= .;:: 0 4 ~% ~d F released with cubs
r~'= ~-"""'" max. density = 0.45 bearslkm2 ~.II~~ .... ~ 0.2 - 0% ad F released with cubs ........... 15% ad F released with cubs o - 15% ad F released with cubs - .. - .................................... v .. voov .. v .... - ... -----............. ftnft
.q O.O~----~,~~~~~~~,~~====~====~,~===T,=-~~BO :-= 0 20 40 60 ~ 1 O~I----------------------------------------------~ ..c . ~ 4 year Program
£ O.B-1 0.6 max. density = 0.25 bears/km2
0.4 . ~ .. ~~ F released with cubs
max. density = 0.45 bears/km2 ~:::.: ..... 0.2 . ~'.:::\::..".. 0% ad F released with cubs
...J 15% ad F released With cubs~ ........ -.. -----.. - .... ~ ....... "n._ __" __ "nl\"ft:"l~",..l'Iftnl\nft"ft 0.0 I 0% ad .F released with cubs .... '""1\ ......... .
o 20 40 60 BO Initial Population Size
APPENDIX II
Appendix 2 - Chi/elli et al. 76
TRANSLOC: a population simulation model
TRANSLOC (Chilelli et ale 1992) is distinguished from other models designed to simulate small populations of birds and mammals in the manner it handles the release of animals to the population. We found that differences between simulated and observed success rates for translocations of birds could be accounted for by assuming increased . . mortality/dispersal in the year of release (Griffith et ale 1991). TRANSLOC is unique among commonly used simulation-models in incorporating this critical factor by specifying--vitalrates for newly released animals (in year following release) separate from those for the existing population.
The sex and age structure of released animals in TRANSLOC can be assigned stochastically, based on user defined sex- and age-ratios, or deterministically, with user specified numbers by sex and age. These 2 methods makes TRANSLOC suitable for simulating capture-and-translocate programs or captive release programs.
In addition to uniquely addressing the important aspects of a translocation program, TRANSLOC incorporates features useful in simulating the dynamics of small populations of birds and mammals. TRANSLOC can simulate populations of short or long-lived ~ 40yr) animals, with a monogamous or polygamous breeding system. The program is integer-based, incorporating demographic stochasticity. Environmental stochasticity can be modeled by imposing variance on survival and reproductive rates. Vital rates are sex- and age-specific, allowing rates to reflect differences within adult age classes if data are available.
The input of reproductive rates allows for 2 options, which should be applicable for most data available for birds and mammals. Probabilities of clutch/litter sizes (ranging from age-specific minimum to maximum) are calculated from binomial distributions with an age-specific mean clutch/litter size. The optional female breeding rate is the age-specific probability of successfully breeding. If this optional breeding rate is included, clutch/litter size is interpreted as the mean clutch/litter size for successfully breeding females. If the optional breeding rate is not selected, clutch/litter size is interpreted as the mean clutch/litter for all adult females
The patterns of correlations among vital rates available within TRANSLOC are based on those observed in nature (Breitenbach et ale 1963, Ransom 1967, Verme 1977, Pattee and Beasom 1979, Barrett 1982, Lavigne 1983, Porter et ale 1983, Hansen 1987, Vander Haegen et ale 1988, Couturier et ale 1990). Within survival rates, all age classes (M and F) can be correlated or age class 0 (M and F) can vary independently of age classes 2..1 (M and F). Breeding rate, clutch/litter size, and survival rate can vary independently or clutch/litter size can be correlated with the previous year's survival rates, with breeding rates varying independently of the other 2 rates. Age classes are correlated within breeding rates and clutch/litter sizes separately. All correlated rates can have unique coefficients of variation specified.
TRANSLOC does not incorporate a density dependence response in vital rates because it tends to reduce net variance in these rates and thereby lower estimates of extinction. Models without a density dependence response are conservative estimators of extinction probabilities (Ginzburg et ale 1990). TRANSLOC can simulate a population growth ceiling
Appendix 2 - Chi/elli et al.
determined by the species life history characteristics (social organization, home range size, and degree of overlap in home ranges) and size of the simulated habitat fragment.
77
The model obtains input values defining conditions for each scenario and vital rates from ASCn fIles. The age- and sex-structure of the simulated population is output annually (after reproduction and survival, before aging) to an ASCn file according to a user selected format.
Each subprogram within TRANSLOC has been verified (Tipton 1980). The program is written in ANSI FORTRAN-77, with Microsoft FORTRAN extensions, and was compiled for use on IBM PC's and compatibles (8088 or later) running MS-DOS (version.2el or later) with the Microsoft Fortran Compiler (version 5.0). The current executable file (56-64K, depending on life history modifications) requires a coprocessor (8087-series), but the program can be recompiled for PCs without one. Copies of the source code, executable fIle, and example data are provided on a diskette enclosed with this report.
Appendix 2 - Chi/elli et al.
General description of the population simulation model TRANSLOC.
GENERAL written in Fortran 77; Input/output as mes, allowing batch processing number of replicates and years per simulation limited only by hardware appropriate for simulating long/short-lived species (upper age class ~ 40) random seed set from 1) input value or 2) computer clock optional stochasticity acting on survival and fecundity rates: 1) demographic only, 2)
environmental and demographic optional format of output population me option to determine released population's structure 1) stochastically or 2) deterministically current year's released animals can have vital rates different from established population
78
no restrictions on length of "release" program, although limited to one release per year Extinction defined as sum of males or females = 0; extinction causes simulation to terminate
outside of release period. However, simulation continues through end of release program, even if population of one sex=O during that time; this prevents premature cessation of release program
can simulate a population growth ceiling determined by the species life history characteristics (social organization, home range size, and degree of overlap in home ranges) and size of the simulated habitat fragment
AGING optional aging of translocated animals in year of release, before reproduction and survival.
May be appropriate for late winter releases
REPRODUCTION option for mating system: monogamous or polygamous; user-defined age at first breeding by
sex option to breed in year translocated option on correlating reproductive rates with survival rates (if incorporating environmental
stochasticity) (age classes are correlated within breeding rates and within litter size): 1) breeding rate, litter size, and survival rate vary independently; 2) litter size correlated with previous year's survival rates, breeding rates vary independently of other 2 rates
option for female breeding rate that is separate from litter size: age-specific probability of breeding that can differ for 1) translocated and 2)
established age-specific c. V. on probability of breeding rates for translocated and established
Probabilities of litter/clutch sizes (ranging from age-specific minimum to maximum) are - calculated from binomial distribution with specified mean that is determined from:
age-specific litter/clutch sizes for 1) translocated and 2) established females age-specific C. V. on litter/clutch sizes for translocated and established females If the optional breeding rate is included, litter/clutch size is interpreted as mean litter/clutch size for successfully breeding females. If the optional breeding rate is not
Appendix 2 - Chi/elli et aZ.
selected, litter/clutch size is interpreted as mean litter/clutch for all adult females. input probability of newborn being female (one rate used throughout scenario)
SURVIVAL
79
optional extra mortality (sex- and age-specific rate, demographic stochasticity) of translocated animals, implemented between release and breeding in year of release. May be appropriate for late winter releases.
option on correlating survival rates (if incorporating environmental stochasticity): 1) all age .. classes, M & F, correlated; 2) ACO (M&F) correlated, 2.,ACI (M&F) correlated, two
groups vary independently. sex- and age-specific survival rates that can differ for 1) translocated and 2) established
animals sex- and age-specific C. V. on survival rates for translocated and established animals
Appendix 2 - Chi/elli et aI. 80
General flow chart for population simulation model TRANSLOC.
TRNSLC
AGE LIMITN CENSUS
UNIF
Appendix 2 - Chi/elli et al.
General description of input and output files for the population simulation model TRANSLOC.
To run program in batch job:
TRANSWC < fname
fname contains: inpop,incond,insurv ,inbred,outpop,inhome in format: (6(AI2, Ix»
81
(inpop, incond, insurv, inbred, outpop, and inhome are dummy names for the input and output flle names you submit to TRANSLOC in format of xxxxxxxx.xxx. )
Bog lemming modifications to TRANSLOC: inpop ,incond ,insurv ,inbred,outpp 1 ,outpp2,inhome
in format: (7(AI2, Ix» (outpp 1 and outpp2 are census of population at end of period 1 and 2 in the yearly cycle.)
Input file description:
1. incond: each value entered on separate line
-
*
*
variable r y uac cf seed iptype
stoch
srvcor
yt xmty
xaty matsys obr
description # replicates # yrs upper age class (1-40) census format(tot,jya,jsa,all) i = input, c=clock input population type
d =deterministic s = stochastic
d(demographic only), e( environmental & demogr.) survival rates correlated
1 : all age classes,M&F 2: ACO(M&F);AC2I (M&F)
last yr of translocation extra mortality transloc. yr
(y,n) extra aging transl. yr (y,n)
m = monogamous,p = pol ygamous optional breeding rate(y or n)
format 14 13 12 A3 Al Al
Al
11
12 Al
Al Al Al
Appendix 2 - Chilelli et al. 82
bam age first breed-males 12 baf age first breed-females 12 maxf2m max. # F bred by one M 12
(polygamous system) probfy prob. newborn female F5.3
** ocubsr orphan cub survival rate adjustment F5.3 rprcor reproductive rates correlated Al
with survival rates: i = birth rate, surv. rate, &
litter size indep. c = litter size correlated with
previous surv. rate, birth rate indep.
redbf # breeding females reduced: Al p = proportionally , s = stochastically
byt breed in yr translocated(y,n) Al dimplt delayed implantation(y,n) Al aup area use pattern II
I = territorial LIyr, sex-specific intrasexual exclusion
2 = general density limitation. if > maximum density, yearlings stochastically lost from population
+ cycle # years in cycle (e.g. 3) 12 + period # different periods in year with 11
different reproductive and survival rates
+ spdI # reproductive/survival segments 11 within period I
+ spd2 # reproductive/survival segments 11 within period 2
If seed = 'i', then
* ** +
2.
rx random integer, >0, <2147483647
variables used only in Fisher incond files variable used only in Black Bear incond files variables used only in Bog Lemming incond files
insurv i: I = males, 2=females
110
srate=mean sex- & age-specific survival rates for wild/established population tsrate=mean sex- & age-specific survival rates for animals translocated in current year xsrate=optional survival rate (sex- & age-specific) between release and breeding in yr
Appendix 2 - Chi/elli et aI.
of release (demographic stochasticity only) scv=C.V. on sex- & age-specific survival rates (srate and tsrate)
file contains values for:
IF (xmty = y) THEN: IF (xmty = y) THEN: IF (stoch = e) THEN: IF (stoch = e) THEN:
Values (srate(1 j)j =O,uac) (srate(2,j),j =O,uac) (tsrate(l j),j =0, uac) (tsrate(2,j),j =O,uac) (xsrate(l ,j),j =O,uac) (xsrate(2j),j =O,uac) (scv(l ,j),j =O,uac) (scv(2,j),j =O,uac)
+ Bog lemming arrays input at (cycle N, period N, i, j)
3. inbred
Format (41(F5.3,lx» (41(F5.3, Ix» (41(F5.3, Ix» (41(F5.3,lx» (41(F5.3,lx» (41(F5.3,lx» (41(F5.3,lx» (41(F5.3,lx»
83
brate=age-specific probability of breeding for wild/established females tbrate=age-specific probability of breeding for females translocated in current year bcv=C. V. on age-specific probability of breeding rates (brate and tbrate) lsize=age-specific litter/clutch size of breeding wild/established females tlsize=age-specific litter/clutch size of breeding females (translocated in current year) Icv=C. V. on age-specific litter/clutch sizes (lsize and tlsize) minls=age-specific minimum litter size maxls=age-specific maximum litter size
file contains values for:
IF (obr=y) THEN: IF (obr=y) THEN: IF(obr=y)&(stoch=e):
IF (stoch=e) THEN:
Values (brate(j),j =O,uac) (tbrate(j),j =O,uac) (bcv(j),j =O,uac) (lsize(j),j =O,uac) (tlsize(j),j =O,uac) (lcv(j),j =O,uac) (minls(j),j =O,uac) (maxls(j),j =O,uac)
+ Bog lemming arrays input at (cycle N, period N, j)
4. inpop pcttfc = percent translocated adult females with cubs
IF (iptype = d) THEN
Format (41(F5.3, Ix» (41(F5.3,lx» (41(F5.3, Ix» (41(F5.2, Ix» (4I(F5.2,lx» (41(F5.3, Ix» (3x,4I(l2,4x» (3x,4I(l2,4x»
tpop=animals translocated in current year, by sex and age class
Appendix 2 - Chi/elli et al. 84
file contains values for: Values Format
(tpop(l,j),j=O,uac) (41(13, Ix).) (tpop(2,j),j =O,uac) (41(13, Ix»
** pettfc (FS. 3) repeat lines I &2 for years I through yt, leaving empty lines for years in which
no animals will be translocated
**
**
S.
** +
IF (iptype = s) THEN n=number of animals translocated in year yt prob=probability (expressed as percentage) each newly translocated animal
belongs to each age and sex category file contains values for:
Values n
(prob(1 ,j),j =O,uac) (prob(2,j),j =O,uac) pettfc
repeat lines 1-3 for years 1 through yt
for Black Bear input files only
·inhome i: 1 = males, 2 = females hfrag = habitat fragment size territ(i)=sex-specific mean territory size of age class 2..lyr. terrcv(i)=C.V. on sex-specific mean territory size termin(i) = sex -specific minimum territory size termax(i)=sex-specific maximum territory size
file contains values for: Values
hfrag (territ(i),i = 1,2) (terrcv(i),i= 1,2) (termin(i),i = 1,2) (termax(i),i = 1,2)
Format (13)
(41(FS.3,lx» (4I(F5.3, Ix» (FS.3)
Format (FS.2) (2(FS.2, Ix» (2(FS.3, Ix» (2(FS.2, Ix» (2(FS.2, Ix»
~* + for bog lemming and black bear simulations, termax = maximum population density
Output file description M(xx) = males of age class xx (ACO=young of the current year) F(xx) = females of age class xx (ACO=young of the current year) run=run #
Appendix 2 - Chi/elli et ale
year = year of simulation
IF (cf = tot) THEN Values
run,year,M(ACO-uac),F(ACO-uac) Format
(lx,I4,lx,I3,2(1x,I6»
IF (cf = jya) THEN Values
run ,year,M(ACO) ,M(AC 1) ,M(AC2..2) ,F(ACO) ,F(ACl),F(AC2..2) Format
(lxt I4,lx,I3,6(lx,I6»
IF (cf = jsa) THEN (see subroutine RELEAS for more detail) is=minimum value (baf,bam) isl =is-l
Values run ,year,M(ACO) ,M(1-is 1) ,M(2,.is) ,F(ACO) ,F(l-is l),F(2,.is)
Format (lx,I4,lx,I3,6(lx,I6»
IF (cf = all) THEN Values
run,year,(MO),j =O,uac),(FO),j =O,uac) Format
(lx,I4,lx,I3,82(lx,I6»
85
Appendix 2 - Chi/elli et al.
Modifications to TRANSLOC to simulate different life history patterns of mammals, with example input and output files.
BOG LEMl\1ING
86
To simulate bog lemming population dynamics, TRANSLOC was modified to incorporate a cyclic pattern in vital rates (TRNSLCMC - TRANSLOC with multiple birth and
. survival periods/year). Each year is divided into user-specific number of periods (with . ,{ period-specific vital rates) (e.g. winter and summer). Within each period, there are user-specific number of survival-reproductive subperiods (e.g. 2 subperiods in winter period, 3 subperiods in the summer period).
To replicate this example run: With the model and input data files in the current directory, type
TRNSLCMC < BLEMINTL.DAT <RETURN>
Example input file BLEMINTL.DAT This file lists the input files read by TRNSLCMC
blempopn.dat blemcond.dat blemsurv.dat blembred.dat blemsot.dat blemwot.dat blemhome.dat
Appendix 2 - Chi/elli et al. 87
Example input ·fiIe BLEMPOPN.DAT In this example, the released population is determined stochastically with inputs for
number of bog lemmings released each year-period and probability (expressed as percentages) each newly translocated bog lemming belongs to a particular sex- and age-class. In each of the translocation years (Years 1-3) 20 bog lemmings will be released at the beginning <?f each summer period (total release = 60 bog lemmings). For bog lemming simulations, ACO are animals born in the current subperiod. AC1 are lemmings <1 yr, not including newborns (ACO).
20 0.000 0.414 0.098 0.021 0.000 0.000 0.000 0.387 0.069 0.011 0.000 0.000
0 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000
20 0.000 0.414 0.098 0.021 0.000 0.000 0.000 0.387 0.069 0.011 0.000 0.000
0 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000
20 0.000 0.414 0.098 0.021 0.000 0.000 0.000 0.387 0.069 0.011 0.000 0.000
0 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000
Appendix 2 - Chi/elli et al. 88
Example input file BLEMCOND.DAT This file contains data that defines the scenario: 800 replicates of 50 years each, 3 year
longevity (AC4), random seed from clock, input population determined stochastically, demographic and environmental stochasticity simulated, bog lemmings translocated in years 1-3, polygamous breeding, optional breeding rate selected, age of first breeding for males and females is AC1 «1 yr), breeding in year of release, area use pattern reflected by general population density ceiling, 3 year cycle, 2 periods within each year, 3 subperiods in period 1, and 2 subperiods in period 2.
800 50 4
jya c s e 1
3
P Y
1 1 5
0.500 i s y n 2
3 2 3 2
Appendix 2 - Chi/elli et ale 89
Example input file BLEMSURV.DAT This file provides the inputs for survival rate and C. V., males and females ACO-4, for Year
I-summer, Year I-winter, Year 2-summer, Year 2-winter, Year 3-sumrner, and Year 3-winter.
0.450 0.710 0.710 0.710 0.000 0.380 0.730 0.730 0.730 0.000 0.450 0.710 0.710 0.710 0.000 0.380 0.730 0.730 0.730 0.000 0.050 0.050 0.050 0.050 0.000 0.050 0.050 0.050 0.050 0.000 0.740 0.830 0.830 0.830 0.000 0.460 0.860 0.860 0.860 0.000 0.740 0.830 0.830 0.830 0.000 0.460 0.860 0.860 0.860 0.000 0.050 0.050 0.050 0.050 0.000 0.050 0.050 0.050 0.050 0.000 0.470 0.800 0.800 0.800 0.000 0.580 0.770 0.770 0.770 0.000 0.470 0.800 0.800 0.800 0.000 0.580 0.770 0.770 0.770 0.000 0.050 0.050 0.050 0.050 0.000 0.050 0.050 0.050 0.050 0.000 0.660 0.770 0.770 0.770 0.000 0.570 0.720 0.720 0.720 0.000 0.660 0.770 0.770 0.770 0.000 0.570 0.720 0.720 0.720 0.000 0.050 0.050 0.050 0.050 0.000 0.050 0.050 0.050 0.050 0.000 0.640 0.710 0.710 0.710 0.000 0.820 0.640 0.640 0.640 0.000 0.640 0.710 0.710 0.710 0.000 0.820 0.640 0.640 0.640 0.000 0.050 0.050 0.050 0.050 0.000 0.050 0.050 0.050 0.050 0.000 0.200 0.670 0.670 0.670 0.000 0.560 0.500 0.500 0.500 0.000 0.200 0.670 0.670 0.670 0.000 0.560 0.500 0.500 0.500 0.000 0.050 0.050 0.050 0.050 0.000 0.050 0.050 0.050 0.050 0.000
Appendix 2 - Chi/elli et ale 90
Example input file BLEMBRED.DAT This file provides the inputs for females for breeding rates (C.V.), litter sizes (C.V.), and
minimum and maximum litter sizes for Year 1-summer, Year 1-winter, Year 2-summer, Year 2-winter, Year 3-summer, and Year 3-winter. In this example, age of first breeding is AC1, breeding rate reflects probability of successfully producing young for females (ACl-4), litter size reflects number of young per litter = 3.00(0.05), and number of youngllitter range from 1-8. These simulated bog lemmings breed in their year of release.
0.000 0.700 0.000 0.700 0.000 0.050 0.00 3.00 0.00 3.00
0.000 0.050 o 1 o 8
0.000 0.480 0.000 0.480 0.000 0.050 0.00 3.00 0.00 3.00
0.000 0.050 o 1 o 8
0.000 0.550 0.000 0.550 0.000 0.050
0.00 3.00 0.00 3.00
0.000 0.050 o 1 o 8
0.000 0.390 0.000 0.390 0.000 0.050 0.00· 3.00 0.00 3.00
0.000 0.050 o 1 o 8
0.000 0.220 0.000 0.220 0.000 0.050
0.00 3.00 0.00 3.00
0.000 0.050 o 1 o 8
0.000 0.140 0.000 0.140 0.000 0.050
0.700 0.700 0.050 3.00 3.00
0.050 1 8
0.480 0.480 0.050 3.00 3.00
0.050 1 8
0.550 0.550 0.050 3.00 3.00
0.050 1 8
0.390 0.390 0.050 3.00 3.00
0.050 1 8
0.220 0.220 0.050 3.00 3.00
0.050 1 8
0.140 0.140 0.050
0.700 0.700 0.050 3.00 3.00
0.050 1 8
0.480 0.480 0.050
3.00 3.00
0.050 1 8
0.550 0.550 0.050 3.00 3.00
0.050 1 8
0.390 0.390 0.050 3.00 3.00
0.050 1 8
0.220 0.220 0.050 3.00 3.00
0.050 1 8
0.140 0.140 0.050
0.700 0.700 0.050 3.00 3.00
0.050 1 8
0.480 0.480 0.050 3.00 3.00
0.050 1 8
0.550 0.550 0.050
3.00 3.00
0.050 1 8
0.390 0.390 0.050 3.00 3.00
0.050 1 8
0.220 0.220 0.050 3.00 3.00
0.050 1 8
0.140 0.140 0.050
Appendix 2 - Chi/elli et al.
0.00 3.00 3.00 3.00 3.00 0.00 3.00 3.00 3.00 3.00
0.000 0.050 0.050 0.050 0.050 0 1 1 1 1 0 8 8 8 8
Example input file BLEMHOME.DAT ., _c,
This file proVides inputs for area use pattern (=2, general density InnIi~tion). Habitat fragment size;::': 4 (ha) and maximUfli. population density = 50 (bog lemming.,lla).
4.00 00.00 00.00
0.000 0.000 0.00 0.00
50.00 50.00
Example output file BLEMWOT.DAT This file contains the annual popUlation census taken at the end of each winter period
91
and before age is incremented and next cycle year begins. In this example, census format=jya and each record contains values for:
run, year, M(ACO). M(ACl). M(AC2-4), F(ACO), F(ACl), F(AC2-4)
1 1 1 2 1 3 1 4 1 5 1 6 1 7 1 8 1 9 1 10
800 40 800 41 800 42 800 43 800 44 800 45 800 46 800 47 800 48 800 49 800 50
1 6 o
13 10
1 10 13
1 8
7 16
3 11 20
4 13 26
1 10 11
5 15
9 18 28 13 18 28 15 20
17 43 16 43 40 16 26 65 21 25 32
o 4 6 2 7 3 2
11 8 6
8 14
6 8
15 15
6 12 15
7 11
1 7 2 7
16 4 9
16 2 6
11 12
4 10 28
3 11 27
5 6
15
4 17
8 13 28 10 13 34
8 16
13 39 12 16 30 12 16 59 10 17 28
1 1 o 4 7 2 3 8 1 2
4 8 3 4 2 3 5
10 2 4
10
Appendix 2 - Chi/elli et aJ.
FISHER
92
To simulate fISher population dynamics, lRANSLOC was revised to incorporate an area use pattern determined by sex-specific home ranges, intrasexually exclusive. Delayed implantation was incorporated into TRANSLOC using the number of adult males in the previous year to determine (based on maxf2m) the maximum number of females that could breed in the current year.
"To replicate this example run: With the model and input data files in the curren.! directory, type
TRANSLOC < FSHRINTL.DAT <RETURN>
Example input file FSHRINTL.DAT This file lists the input files read by TRANSLOC
fshrpopn.dat fshrcond.dat fshrsurv.dat fshrbred.dat fshrout.dat fshrhome.dat
Example input file FSHRPOPN.DAT In this example, the released population is determined stochastically with inputs for
number of fishers released each year and probability (expressed as percentages) each newly translocated fisher belongs to a particular sex- and age-class. In each of the translocation years (Years 1-3) 10 fIShers will be released (total release = 30 fishers). No juveniule fISher are beinging released in this example.
10 0.000 0.106 0.080 0.061 0.0460.035 0.0260.020 0.015 0.011 0.009 0.006 0.005 0.004 0.003 0.002 0.000 0.1060.088 0.072 0.060 0.049 0.040 0.033 0.027 0.023 0.019 0.015 0.013 0.010 0.009 0.007
10 0.000 0.106 0.080 0.061 0.0460.035 0.0260.020 0.015 0.011 0.0090.0060.005 0.004 0.003 0.002 0.000 0.106 0.088 0.072 0.060 0.049 0.040 0.033 0.0270.023 0.0190.015 0.0130.0100.0090.007
10 0.000 0.106 0.080 0.061 0.0460.035 0.026 0.020 0.015 0.011 0.009 0.006 0.005 0.004 0.003 0.002 0.0000.1060.088 0.072 0.060 0.049 0.0400.0330.0270.0230.0190.015 0.0130.0100.0090.007·
Appendix 2 - Chilelli et ale 93
Example input file FSHRCOND.DAT This file contains data that defines the scenario: 800 replicates of 50 years each, 15 year
longevity, random seed from clock, input population determined stochastically, demographic and environmental stochasticity simulated, fishers translocated in years 1-3, polygamous breeding, optional breeding rate selected, and age of first breeding for males and females is 2 years. Because breeding and birth are accomplished within 1 year in lRANSLOC, age of first breeding for females was input as 2, actually reflecting age that first give birth. Additionally, breeding in year of release is selected, delayed implantation is implemented, and a territorial area use pattern is selected, with sex-specific home ranges, intrasexual}y_exclusive.
800 50
15 jya c s e 1·
n n p y
3
2 2 5
0.500 i s y y 1
Example input file FSHRSURV.DAT This file provides the inputs for annual survival rate (C.V.), males and females, for
juveniles [0.329,0.329(0.100)], >lyear-olds [0.756,0.824(0.050)]. There is no reduction in survival rate during year of release.
0.329 0.756 0.756 0.756 0.756 0.756 0.756 0.756 0.756 0.756 0.756 0.756 0.756 0.756 0.756 0.000 0.329 0.824 0.824 0.824 0.824 0.824 0.824 0.824 0.824 0.824 0.824 0.824 0.824 0.824 0.824 0.000 0.329 0.756 0.756 0.756 0.756 0.756 0.756 0.756 0.756 0.756 0.756 0.756 0.756 0.756 0.756 0.000 0.329 0.824 0.824 0.824 0.824 0.824 0.824 0.824 0.824 0.824 0.824 0.824 0.824 0.824 0.824 0.000 0.1000.050 0.050 0.050 0.050 0.050 0.050 0.050 0.050 0.050 0.050 0.050 0.050 0.050 0.050 0.000 0.1000.050 0.050 0.050 0.050 0.050 0.050 0.050 0.050 0.050 0.050 0.050 0.050 0.0500.0500.000
Appendix 2 - Chi/elli et al. 94
Example input file FSHRBRED.DAT This file provides the inputs for females for breeding rates (C.V.), litter sizes (C.V.), and
minimum and maximum litter sizes. In this example, age of first producing young is 2yr, breeding rate reflects probability of successfully producing young for females [2-3 year-olds (0.300(0.050», 4-7 year-olds (0.750(0.050», >8-year-olds (0.500(0.050»], litter size reflects number of young per litter = 2.80(0.05) for 2-year-olds and 3.10(0.050) for >3-year-olds, and number ofyoungllitter range from 1-5. These simulated fishers can give birth in their year of release.
0.000 0.000 0.300 0.300 0.750 0.750 0.750 0.750 0.500 0.500 0.500 0.500 0.500 0.500 0.500 0.500 0.000 0.000 0.300 0.300 0.750 0.750 0.750 0.750 0.500 0.500 0.500 0.500 0.500 0.500 0.500 0.500 0.000 0.000 0.050 0.050 0.050 0.050 0.050 0.050 0.050 0.050 0.050 0.050 0.050 0.050 0.050 0.050 0.00 0.00 2.80 3.10 3.10 3.10 3.10 3.10 3.10 3.10 3.10 3.10 3.10 3.10 3.10 3.10 0.00 0.00 2.80 3.10 3.10 3.10 3.10 3.10 3.10 3.10 3.10 3.10 3.10 3.10 3.10 3.10
0.000 0.000 0.050 0.050 0.050 0.050 0.050 0.050 0.050 0.050 0.050 0.050 0.050 0.050 0.050 0.050 0011111111111111 o 055 5 5 555 5 5 5 5 555
Example input file FSHRHOME.DAT This file provides inputs for area use f,attern (= 1, sex-specific home ranges, intrasexually
exclusive). Habitat fragment size = 235 (km ). Mean home range size (C.V.) for males and 2 females = 30.9 km2(0.40) and 16.3 km2(0.40), ranging 10.6-78.2 km2 for males and 8.1-39.1 km for females.
235.00 30.90
0.400 0.400 10.60 78.20
16.30
8.10 39.10
Appendix 2 - Chilelli et aI.
Example output file FSHROUT.DAT This file contains the annual population census taken after annual mortality and before
age is incremented and next birth cycle begins. In this example, census format=jya and each record contains values for:
run, year, M(ACO), M(AC1), M(AC2-15), F(ACO), F(AC1), F(AC2-15)
1 1 1 2 1 3 1 4 1 5 1 6 1 7 1 8 1 9 1 10
800 40 800 41 800 42 800 43 800 44 800 45 800 46 800 47 800 48 800 49 800 50
BLACK BEAR
o 2 o o o 3 1 1 1 1
3 2 2 1 0 2 0 2 2 0 1
2 1 3 o o o 1 1 1 1
0 1 1 1 1 0 2 0 2 2 0
2 5
12 9 7 4 3 2 1 2
2 1 1 1 1 2 0 2 2 4 5
1 1 o 2 1 4 o 1 o 1
1 1 1 1 1 0 2 0 2 0 1
1 1 2 o 2 1 3 o 1 o
0 1 1 1 1 1 0 2 0 1 0
4 10
8 8 6 7 6 7 6 5
5 4 2 3 4 5 4 4 6 2 3
95
To simulate black bear population dynamics, TRANSLOC was modified to incorporate the 2-year reproductive cycle for black bears and the correlation pattern between survival and reproductive rates evident in black bear population dynamics - habitat quality (fall food supply) efffects proportion of females successfully giving birth in the winter and the first year survival of those cubs (TRNSLCBB). Orphaned cubs can have a reduced survival rate. Population growth was restricted using a maximum population density limitation.
To replicate this example run: With the model and input data files in the current directory, type
TRNSLCBB < BEARINTL.DAT <RETURN>
Appendix 2 - Chi/elli et al. 96
Example input file BEARINTL.DAT This file lists the input files read by TRNSLCBB
bearpopn.dat beareond.dat bearsurv.dat bearbred.dat bearout.dat bearhome.dat
Example input file BEARPOPN.DAT _._ - In this example, the released population is determined stochastically with inputs for number of black bears released each year and probability (expressed as percentages) each newly translocated black bear belongs to a particular sex- and age-class. In each of the translocation years (Years 1-2) 10 bears will be released (total release = 20 black bears). Number of cubs released is determined based on percent of translocated females with cubs (15%) and last years stochastic breeding rate.
10 0.000 0.063 0.038 0.023 0.014 0.008 0.005 0.003 0.002 0.001 0.001 0.000 0.000 0.000 0.000 0.000 ••• 0.000 0.000 0.119 0.103 0.088 0.076 0.065 0.0560.0480.041 0.0360.031 0.0260.023 0.0190.0170.014 ••• 0.002 0.15
10 0.000 0.063 0.038 0.023 0.014 0.008 0.005 0.003 0.002 0.001 0.001 0.000 0.000 0.000 0.000 0.000 ••• 0.000 0.000 0.119 0.103 0.088 0.076 0.065 0.0560.0480.041 0.0360.031 0.026 0.023 0.0190.0170.014 ••• 0.002 0.15
Appendix 2 - ChileIli et al. 97
Example input file BEARCOND.DAT This file contains data that deqnes the scenario: 800 replicates of 50 years each, 30 year
longevity, random seed from clock, input population determined stochastically, demographic and environmental stochasticity simulated, bears translocated in years 1-2, polygamous breeding, optional breeding rate selected, age of first breeding for males and females = 2 years, orphaned cubs survival rate reduced 10% from that of cubs remaining with mothers, breeding in year of release, and area use pattern reflected by general population density ceiling is selected.
800 50
30 jsa c s e 2
2 P Y
2 2
10 0.500 0.900 c s y n 2
Example input file BEARSURV.DAT This file provides the inputs for annual survival rate (C.V.), males and females, for
juveniles [0.40,0.76(0.15)], > 1year-olds [0.60,0.86(0.10)]. There is no reduction in survival rate during year of release.
0.400 0.600 0.600 0.600 0.600 0.600 0.600 0.600 0.600 0.600 0.600 0.600 0.600 0.600 0.600 0.600 ••• 0.000 0.760 0.860 0.860 0.860 0.860 0.860 0.860 0.860 0.860 0.860 0.860 0.860 0.860 0.860 0.860 0.860 ••• 0.000 0.400 0.600 0.600 0.600 0.600 0.600 0.600 0.600 0.600 0.600 0.600 0.600 0.600 0.600 0.600 0.600 ••• 0.000 0.760 0.860 0.860 0.860 0.860 0.860 0.860 0.860 0.860 0.860 0.860 0.860 0.860 0.860 0.860 0.860 ••• 0.000 0.1500.1000.1000.1000.1000.1000.1000.1000.100 0.100 0.100 0.100 0.100 0.1000.1000.100 ••• 0.000
0.150 0.100 0.100 0.100 0.100 0.100 0.100 0.100 0.100 0.100 0.100 0.100 0.100 0.100 0.100 0.100 ••• 0.000
Appendix 2 - Chi/elli et ale 98
Example input file BEARBRED.DAT This file provides the inputs for females for breeding rates (C.V.), litter sizes (C.V.), and
minimum and maximum litter sizes. In this example, age of first breeding is 2-years-old, breeding rate reflects probability of successfully producing young for females [2-year-olds (0.17(0.10», 3-year-olds (0.60(0.10», >4-year-olds (0.80(0.10»], litter size reflects number of young per litter = 2.30(0.05), and number of youngllitter range from 1-4. These simulated bears can breed in their year of release.
0.000 0.000 0.170 0.600 0.800 0.800 0.800 0.8000.800 0.800 0.800 0.800 0.800 0.800 0.800 0.800 •• , 0.800 0.000 0.000 0.170 0.600- D.-gOO 0.800 0.800 0.800 0.800 0.800 0.800 0.800 0.8000.800 0.800tT:"gOO ••• 0.800 0.000 0.000 0.100 0.100 0.100 0.100 0.100 0.100 0.100 0.100 0.100 0.100 0.100 0.100 0.100 0.100 ••• 0.100 0.00 0.00 0.00 2.30 2.30 2.30 2.30 2.30 2.30 2.30 2.30 2.30 2.30 2.30 2.30 2.30 •• , 2.30 0.00 0.00 0.00 2.30 2.30 2.30 2.30 2.30 2.30 2.30 2.30 2.30 2.30 2.30 2.30 2.30 ••• 2.30
0.000 0.000 0.000 0.050 0.050 0.050 0.050 0.050 0.050 0.050 0.050 0.050 0.050 0.050 0.050 0.050 ••• 0.050 o 0 0 1 1 '1 1 1 1 1 1 1 1 1 1 1 ••• 1 o 0 0 4 4 4 4 4 4 4 4 4 4 4 4 4 ••• 4
Example input file BEARHOME.DAT This file provides inputs for area use pattern (=2, general density limitation). Habitat
fragment size = 250 (km2) and maximum population density = 0.25 (bears/km2).
250.00 0.00 0.00
0.000 0.000 0.00 0.00 0.25 0.25
Appendix 2 - Chi/elli et ale
Example output file BEAROUT.DAT This file contains the annual population census taken after annual mortality and before
age is incremented and next birth cycle begins. In this example, census format=jsa and each record contains values for:
run, year, M(ACO), M(ACl), M(AC2-30), F(ACO), F(ACl), F(AC2-30)
1 1 1 2
-1-- ~-·3
1 4 1 5 2 1 2 2 2 3 2 4 2 5
800 40 800 41 800 42 800 43 800 44 800 45 800 46 800 47 800 48 800 49 800 50
o 3 4 1 o o 3 3 o 3
4 5 0 0 7 2 1 3 3 2 3
o o o o o o o 2 2 o
3 0 4 0 0 5 1 1 1 2 1
1 1 o o o 1 o o 2 3
.1 2 1 3 2 2 4 5 3 3 3
o 4 8 3 o o 4 4 o 4
6 8 2 6 8 8
12 8 8 5
12
1 2 2 7 3 1 o 3 3 o
8 5 8 2 5 7 5
10 6 8 5
7 -15 13 12 17
6 12 11
8 7
40 42 47 51 40 38 36 35 41 42 38
99
United States Department of the Interior
December 10th, 1998
U.S. GEOLOGICAL SURVEY Patuxent WiLdLife Research Center
Cooperative Park Studies Unit University of Maine 5768 South Annex A
Orono, ME 04469-5768 Phone: (207) 581-2873
Fax: (207) 581-1743
'" .' '\
To: Chief Scientist, National Park Service, New England System Support Office
From: Leader, CPSU, University of Maine
Subject: Acadia NP Population Viability Report
Enclosed please find three unbound copies of the subject final report. Based on Dr. Underwood's comments we have either modified the report or explained why we did not feel a revision was either necessary or appropriate. In addition, because this project has generated many questions and comments, I have provided a detailed history to serve as a paper trail and to insure that everyone is aware of the sequence of events that has brought us to this juncture.
In January of 1989 when I arrived at Acadia NP, the Park's Resource Management Plan (RMP) included a project statement about the possible reintroduction of fisher onto MDI. The project statement was prepared by Carol Schell, the former resource manager at Acadia. Upon my arrival in Maille, funding was already secured in the amount of75K through the NRPP program. If! remember correctly, the funds were to become available in 1990 and then again for 2 subsequent years (25K/year). Upon learning of the availability ofthese funds, and then consulting with Len Bobinchock and former ACAD superintendent Hauptman, I began discussions with some faculty members in the Wildlife (currently known as "Wildlife Ecology") Department at the University of Maine. I first spoke with Dr. Daniel Harrison, who at the time was working on browsing issues related to herbivores at Acadia and had previous experience with furbearers. It was his idea initially (and in my opinion, a good one) that the funds be used for some type of modeling project, especially prior to attempting what would be a sensitive and controversial reintroduction (i.e., predatory furbearer) on MDI. I followed Dr. Harrison's suggestion, and spoke with Dr. Brad Griffith, the then new assistant unit leader for the Maine Cooperative Fish and Wildlife Research Unit. Dr. Griffith had previous experience in modeling popUlation dynamics and species' translocations. After further discussions, we prepared an interagency agreement between the NPS and U.S. Fish and Wildlife Service (USFWS) to move funds to the Cooperative Units Division (USFWS) for eventual transfer to the University of Maine. Dr. Griffith (with me as a co-investigator) was to begin a modeling project.
-2-. "'-After some futile attempts to find a graduate student for this project, Dr. MaryEllen"Chilelli, then working as a research associate for the Maine Cooperative Fish and wildlife Research Unit, was hired to conduct the actual work of compiling data for input into the model "TRANSLOC". TRANSLOC was first developed'for use with birds by Drs. Chilelli, Griffith, and J. Gilbert, also of the University of Maine. Soon after the work on the Acadia project began, Dr. Griffith left his position at the University of Maine, and Dr. Gilbert was brought on to serve as the principal investigator. The appropriate paper work on this project reflects this change, and Dr. Griffith remained involved in the project as a "scientific advisor".
The decision to model two species (in addition to the fisher), black bears and the southern bog lemming, was essentially a decision made by myself and Drs. Chilelli and Gilbert, with some consultation by Dr. Griffith. The use of the bog lemming in this project was originally mine, coming after a review of park-based information; the bog lemming was documented as occurring on MDI and mentioned in the Park's RMP. The species is at the edge of its geographic range in central Maine, and as with many species, viability becomes less certain when important resources diminish (i.e., often common along the edge of a range).
I am confident now, as I was then, that the three species selected represented a good range of information from which the park could begin to understand the potential (or lack of) for reintroducing vertebrates. Given the amount of money available and the effort required to compile a database for model simulation for three species, the NPS received a credible report for this project. I was somewhat surprised by Dr. Underwood's comments about the "number of species modeled in this report" with the implication that more species be included. As a modeler himself, he is surely aware of the time and effort required to construct the necessary databases for each species. I can only assume that Dr. Underwood was not aware of the events as described above.
Response to major comments by Dr. Underwood:
Paragraph #2
From the perspective as former Chief of Resource Management for Acadia NP, I am comfortable that the amount of work conducted on this project was appropriate. My own experience with NPS resource management also supports the use of graphics as presented in this document. It is always important to insure the most effective method of communication, especially to managers. As you know, NPS resource managers and superintendents are often faced with attempting to understand information on a variety of disciplines. Use of graphs is often the most appropriate method to convey results, especially when there is little time to read an entire technical document (i.e., explaining the details of computer simulations). Further, we have already entertained comments about the difficulty in understanding this report, and toward that end, we elected to leave in the graphics. Elimination of the graphs will only obscure the results for management interpretation. Currently, the report has relatively little text; readers, with the possible exception of other individuals interested in modeling, tend to get bogged down with too much text (and too little graphics!).
-3-
The report contains model syntax (as Dr. Underwood notes in paragraph #3 of his response), and a general review of the model for those interested. Some examples of output are in Appendix 3. To add more syntax, would simply overwhelm most resource managers; in fact, I doubt that most NPS management officials are interested in the detailed computer statements engaging how this model works.
Paragraph #3
The model is "individual" based, and this has been so noted in the report.
Paragraph #4
It is not clear from the first part of this paragraph what type of information is being requested. Density-dependence rates were not incorporated, and we referenced the article by Ginzburg et al (1990). We also have added a few sentences to further clarify this approach and added Boyce's (1992) reference to support our technique. In addition, if sufficient habitat is available, densitydependence is not a determinant of reintroduction success.
To insure that this model performs accurately, we attempted to gather and include authentic biological information, yet where adequate data were not available (i.e., for density dependent rates) we chose not to include what amounts to hypothetical rates. This approach would likely lower extinction rates, thus giving false hopes to NPS officials contemplating possible reintroductions. As you know, there have already been far too many failed attempts at wildlife reintroductions, e.g., Caribou reintroduction in Maine.
Paragraph #5
As Dr. Underwood points out, the use of popUlation ceilings is conservative, and in an area like MDI, a conservative approach is prudent from a political as well as ecological perspective when considering species reintroductions. In addition, in a real introduction, a manager would have little or no control over immigration. Furthermore, as pointed out in the report, the success of fisher and bear introductions on MDI would be linked to mainland populations.
We appreciate Dr. Underwood's review. Unfortunately, due to the somewhat convoluted history of this project, he was unaware of the many circumstances behind the evolution ofthis work. Hopefully, this memo describes fully those events. We hope that you will be able to include·this report in your regional technical series, and if possible, we would like to obtain four copies of the bound report (one for each of the investigators). I have deposited a full set of35mm slides at the park (essentially all the figures found in the report).
If you have any questions please contact me immediately at 207581-2873. We look forward to future cooperative ventures with the NPS.
Encl.laoc
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