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    SPACE USE PATTERNS OF MOOSE (ALCES ALCES) IN RELATION TO

    FOREST COVER IN SOUTHEASTERN ONTARIO, CANADA

    A thesis submitted to the Committee on Graduate Studies

    in partial fulfillment of the requirements

    for the degree of

    Master of Science

    in the faculty of Arts and Science

    TRENT UNIVERSITY

    Peterborough, Ontario, Canada

    Copyright by Karen Hussey, 2009

    Environmental and Life Sciences Graduate Program

    January 2010

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    Space use patterns of moose (Alces alces) in relation to

    forest cover in southeastern Ontario, Canada.

    ABSTRACT

    I investigated habitat use relative to distance to cover of moose (Alces alces) in

    Algonquin Provincial Park, Ontario, Canada to validate assumptions in the Ontario

    Ministry of Natural Resources (OMNR) habitat suitability model for moose. I compared

    distances to cover of 21 GPS-collared female moose to random points within seasonal

    home ranges to determine selection and calculate several distance-to-cover parameters.

    At the population level moose showed no selection for proximity to cover in the summer

    and marginal selection in the winter. When considering four habitat types, moose

    generally showed no selection for proximity to cover in either season while in any of the

    habitat groups. Considerable variation in selection for cover existed within and among

    individuals, with many individuals selecting proximity to cover in one year and avoiding

    or showing no selection in other years. I identified several areas where the existing

    habitat suitability model could be improved. I recommend further testing of an adapted

    model that 1) redefines stand age according to the most recent harvest date instead of the

    age of the oldest trees, 2) adopts a broader list of cover types defined as cover in the

    growing season, and 3) increases the distance moose are assumed to travel through open

    areas in the dormant season from 200 to 300 meters.

    Keywords:Alces alces, Algonquin Provincial Park, cover, distance, habitat, habitat

    suitability model, home range, moose, Ontario, ungulate

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    ACKNOWLEDGMENTS

    I am indebted to many who have provided me with assistance and support

    throughout the project. First of all I would like to thank my supervisors Brent Patterson of

    the Ontario Ministry of Natural Resources (OMNR) and Dennis Murray of Trent

    University for the great opportunity to be a part of the moose project and for their

    financial and academic contributions. Id also like to thank my third committee member,

    Bruce Pond, of the OMNR for his thoughtful input and supportive demeanor. Funders of

    the project included the Natural Sciences and Engineering Research Council of Canada

    (NSERC), Ontario Federation of Anglers and Hunters (OFAH), Canada Foundation for

    Innovation (CFI), OMNR Wildlife Research & Development Section, and Ontario Parks

    (Algonquin Provincial Park). Id especially like to thank the Algonquin Forestry

    Authority (AFA) for providing the critical funding allowing me to finish my degree.

    I am deeply indebted to several office extras who generously shared their time

    and expertise during numerous and impromptu occasions: Raul Ponce-Hernandez, Joe

    Nocera, Jeff Bowman, and especially Kevin Middel and Colin Garroway, for without

    their technical help, I would still be processing my sea of data. Phil Elkie of OMNR

    provided assistance with technical aspects of the model and Joe Yaraskavitch, Keith

    Fletcher, and Gord Cumming of AFA answered all the forestry-related questions I could

    throw at them. Id especially like to thank Linda Cardwell who is a pillar of support for

    all of us graduate students and tirelessly holds the Environmental and Life Sciences

    Department together.

    There are many who have assisted with moose captures and/or field work: Andy

    Silver, Stacey Lowe, Ken Mills, John Benson, Kevin Downing, Kiira Siitari, Josh Sayers,

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    Tom Habib, Mike Ward, and especially Karen Loveless (aka Kwolf) who ran the field

    component until I arrived and was a wonderful field mentor and friend from the

    beginning.

    Lastly, Id like to thank my friends and family for all their support and especially

    my husband, Travis Hussey, who sacrificed so much to join me on this journey. I cant

    imagine completing this endeavor without all your love, support, patience, and tasty

    dinners. Thank you, Travis, from the bottom of my heart.

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    TABLE OF CONTENTS

    Page

    ABSTRACT...iiACKNOWLEDGEMENTS... iiiTABLE OF CONTENTS...vLIST OF TABLES..... viLIST OF FIGURES....... viii

    CHAPTER 1: INTRODUCTION AND LITERATURE REVIEW. 1CHAPTER 2: METHODS.... 5

    2.1 Study area.52.2 Field methods....... 7

    2.3 Habitat data and validation...... 82.4 Analyses... 11

    2.4.1 Selection of cover..... 11

    Population level selection . .... 11Home range level selection.... 14Year effect..15

    2.4.2 Distance parameters...... 152.4.3 Model validation... 18

    Model description.. 18Validation method 1...20

    Validation method 2. ..21

    Validation method 3...22CHAPTER 3: RESULTS...... 22

    3.1 Selection of cover year effect... 233.2 Selection of cover home range level.... 24

    3.3 Population level seasonal results (selection & distance parameters).... 263.4 Population level habitat results (selection & distance parameters).. 273.5 Model validation.. 38

    3.5.1 Validation method 1......383.5.2 Validation method 2..... 41

    3.5.3 Validation method 3..... 45CHAPTER 4: DISCUSSION 46

    4.1 Selection of cover............ 464.1.1 Prediction 1... 464.1.2 Prediction 2... 484.1.3 Prediction 3... 49

    4.2 Model validation.......... 494.3 Model recommendations. 544.4 Implications of variability in habitat studies. ...... 55

    LITERATURE CITED.. 59APPENDIX A: delineation of habitat groups, seral stages, and cover values...........69APPENDIX B: selection ratio normality plots.......... 72

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    LIST OF TABLES

    Page

    Table 2.1: The Ontario Ministry of Natural Resources habitat suitability models

    description of cover categories (Naylor et al. 1999) and mycorresponding habitat groups.. 20

    Table 2.2: Distance-to-cover assumptions in the Ontario Ministry of NaturalResources habitat suitability model for moose and expected 95

    percentile distances from moose locations to distance categories ........ 20

    Table 3.1: Mean temperature and snow depths ( SD) for the analysis periodstaken from Algonquin Park East Gate weather station (EnvironmentCanada 2008). Historic normals are averaged from 1971-2000. Year

    effect analyses were performed using growing season and midwinterseason. Asterisks indicate snow depths known to influence moosemovement........24

    Table 3.2a: Results of habitat group level mature conifer cover selectionANOVAs. Asterisks indicate marginal significance. ........ 29

    Table 3.2b: Results of habitat group level selection of the lesser cover categoriesassociated with presapling and sapling in the dormant season.Asterisks indicate marginal significance. Sapling plus refers to thecombination of any sapling or mature forest. ........ 29

    Table 3.3a: Moose median observed and expected distances to cover plus 95%confidence intervals (in meters) by season and habitat group for allhome ranges, those where cover was selected, and those where coverwas avoided. N refers to the number of home ranges in each group.%S = % home ranges showing selection, %NS = % showing noselection, and %A = % showing avoidance. . 30

    Table 3.3b: Moose observed and expected ninety-five percentile distances plus

    95% confidence intervals (in meters) to cover by season and habitatfor all home ranges, those where cover was selected, and those wherecover was avoided. N refers to the number of home ranges in each

    group. %S = % home ranges showing selection, %NS = % showingno selection, and %A = % showing avoidance....................................... 31

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    Table 3.4a: Moose observed and expected median distances plus 95% confidenceintervals (in meters) to lesser cover categories associated withpresapling and sapling in the dormant season for all home ranges,

    those where cover was selected, and those where cover was avoided.N refers to the number of home ranges in each group. Sapling plusrefers to the combination of any sapling or mature forest. . 32

    Table 3.4b: Moose observed and expected ninety-five percentile distances plus95% confidence intervals (in meters) to lesser cover categoriesassociated with presapling and sapling in the dormant season for allhome ranges, those where cover was selected, and those where coverwas avoided. N refers to the number of home ranges in each group.Sapling plus refers to the combination of any sapling or matureforest....... 32

    Table 3.5: Breakdown of distance assumption violations for the dormant season.The mature conifer assumption refers to points greater than 1600

    meters from cover. Mature forest assumption refers to points greaterthan 400 meters from all mature habitat groups (hardwood, mixed,and cover). Sapling plus assumption refers to points greater than200 meters from saplings and all mature habitat groups combined. Nrefers to the number of animals associated with each result. * The sum

    of distance assumption violations 1 - 3 may exceed 100% in a givenhabitat group because some points violated more than one

    assumption.. 45

    APPENDIX A

    Table 1: Forest Resource Inventory Landscape Guide Forest Units (LGFU)

    included in the three forest types used in this study... 69

    Table 2: Delineation ofseral stages for my study groups in relation to theForest Resource Inventory Landscape Guide Forest Units (LGFUs)that make up each study group. LGFU descriptions are located in

    Appendix A Table 1 70

    Table 3: Delineation ofcover values for my mature study groups in relation tothe Forest Resource Inventory Landscape Guide Forest Units(LGFUs) that make up each study group. LGFU descriptions arelocated in Appendix A, Table 1. Cover values apply to forest standsclassified in the FRI as immature, mature, or old... 71

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    LIST OF FIGURES

    PageFigure 2.1: Study area- Algonquin Provincial Park in southeastern Ontario,

    Canada ..... 7

    Figure 2.2a: Observed and expected distributions of distance-to-cover fromhardwood locations for Moose7 in the dormant season of 2006-2007.Preference zone edge can be estimated as the general area where theexpected values begin to outnumber the observed values...... 17

    Figure 2.2b: Linear regression for Moose7 in the dormant season of 2006-2007when in hardwood stands. The preference zone is the area within 394

    meters of cover. A Y value of 0.301 is equal to the selection ratio ofone .. 18

    Figure 3.1a: Variation of selection behavior at the home range level for matureconifer cover. S = selection, A = avoidance, and NS = no selection. Nrefers to the number of home ranges in each category. 25

    Figure 3.1b: Variation of selection behaviour at the home range level for the lesser

    cover categories associated with presapling and sapling forest in thedormant season (mature forest and sapling plus). S = selection, A

    = avoidance, and NS = no selection. N refers to the number of home

    ranges in each category. ..... 26

    Figure 3.2a: Moose observed (o) and expected (e) average median distances tocover ( 95% CI) of home ranges where selection of cover occurred

    for each season and habitat group. %S is the percent of all homeranges where cover was selected and n is the number of home ranges

    where cover was selected 33

    Figure 3.2b: Moose observed (o) and expected (e) average 95 percentile distances

    to cover ( 95% CI) of home ranges where selection of coveroccurred for each season and habitat group. %S is the percent of all

    home ranges where cover was selected and n is the number of homeranges where cover was selected ... 34

    Figure 3.2c: Moose average preference zones for cover ( 95% CI) for each seasonand habitat group. %S is the percent of all home ranges where coverwas selected and n is the number of home ranges where cover wasselected... .... 35

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    Figure 3.3a: Moose observed (o) and expected (e) average median distances (

    95% CI) to lesser cover categories associated with presapling andsapling forest in the dormant season for home ranges where selection

    of cover occurred. Sapling plus refers to the combination of anysapling or mature forest. %S is the percent of all home ranges wherecover was selected and n is the number of home ranges where cover

    was selected.... 36

    Figure 3.3b: Moose observed (o) and expected (e) average 95 percentile distances

    ( 95% CI) to lesser cover categories associated with presapling andsapling forest in the dormant season for home ranges where selectionof cover occurred. Sapling plus refers to the combination of anysapling or mature forest. %S is the percent of all home ranges where

    cover was selected and n is the number of home ranges where cover

    was selected .... 37

    Figure 3.3c: Moose average preference zones ( 95% CI) in relation to lessercover categories associated with presapling and sapling in the dormantseason. Sapling plus refers to the combination of any sapling ormature forest. %S is the percent of all home ranges where cover was

    selected and n is the number of home ranges where cover was selected.... 38

    Figure 3.4a: Map of the growing season range calculated in OMNRs moosehabitat suitability model and the seasonal moose locations falling in

    and outside of the available habitat in the southwestern portion ofAlgonquin Provincial Park, Ontario, Canada. Distance assumptionviolations occurred in 49% of moose locations.......... 40

    Figure 3.4b: Map of the dormant season range calculated in OMNRs moosehabitat suitability model and the seasonal moose locations falling inand outside of the available habitat in the southwestern portion ofAlgonquin Provincial Park, Ontario, Canada. Distance assumptionviolations occurred in 0.1% of moose locations. 41

    Figure 3.5a: Map of the growing season range created from my adapted model and

    the seasonal moose locations falling in and outside of the availablehabitat in the southwestern portion of Algonquin Provincial Park,Ontario, Canada. Distance assumption violations occurred in 3% ofmoose locations... 42

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    Figure 3.5b: Map of the dormant season range created from my adapted model andthe seasonal moose locations falling in and outside of the availablehabitat in the southwestern portion of Algonquin Provincial Park,

    Ontario, Canada. Distance assumption violations occurred in 12% ofmoose locations... 43

    APPENDIX B

    Figure 1: Distance to cover selection ratio normality plots for moose inAlgonquin Park by year-season for year affect analysis. 72

    Figure 2: Distance to cover selection ratio normality plots for moose inAlgonquin Park by season.. 73

    Figure 3: Distance to cover selection ratio normality plots for moose inAlgonquin Park by habitat group-season 74

    Figure 4: Distance to cover selection ratio normality plots for moose inAlgonquin Park for lesser cover categories 75

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    CHAPTER 1: INTRODUCTION & LITERATURE REVIEW

    Because cover provides protection from harsh environmental conditions and

    concealment from predators, it is a critical habitat component for species of many taxa,

    including insects (Sih 1990), fish (Gilliam and Fraser 1987), amphibians (Holomuzki

    1986) , birds (Radford et al. 2005), and mammals (Holmes 1984, Kotler and Blaustein

    1995). How ever, these protective areas are often deficient in other high quality resources

    (typically food) needed to adequately sustain individuals and/or facilitate reproduction

    (Lima and Dill 1990, Mysterud and stbye 1995, Moody et al. 1996, Dussault et al 2004,

    2005, Sinclair et al. 2006, p. 69). Consequently individuals must make trade-offs to

    maximize fitness and often this involves deciding how far to stray from cover to acquire

    resources.

    For moose and other ungulates, cover can be important in all seasons for reasons

    including protection from predation, and relief from deep snow, heat, or extreme cold and

    wind (Peek 1997, pp. 368-372). Moose are susceptible to predation from wolves, bears

    and humans (Van Ballenberghe and Ballard 1994). To hide from predators, ungulates

    need lateral cover which is comprised of dense low and mid-level vegetation that breaks

    up the shape of their bodies making them harder to detect by coursing predators

    (Timmermann and McNicol 1988, Mysterud and Ostbye 1999, Altendorf et al. 2001,

    White and Berger 2001). Concealment cover is presumed to be especially critical for

    moose calves because of their high susceptibility to predation, with various studies

    reporting neonate predation-induced mortality to be between 30 and 70% (Franzmann et

    al. 1980, Ballard et al. 1981, Larsen et al. 1989, Osborne et al. 1991, Gasaway et al. 1992,

    Garner 1994).

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    Deep snow is energetically costly for any ungulate species and although moose

    are well-adapted for this condition, their movements can still be limited by snow depth

    and condition, especially for calves. As snow depth increases, movement becomes more

    costly and eventually moose need to shift to habitats dominated by mature conifers with

    less snow accumulation (Coady 1974, Timmermann and McNicol 1988, Courtois et al.

    2002). Depths of 70 cm impede moose movement and at 90-100 cm moose are confined

    to areas with a dense coniferous canopy (Coady 1974). Peterson and Allen (1974) found

    that more calves on Isle Royale were killed when snow depths exceeded 76 cm and

    Loveless (2009) found that wolves in Algonquin Park consumed the most moose biomass

    when snow depth was highest. In addition to lower snow depths, dense coniferous

    canopies provide softer snow often making travel easier for moose. In a mild winter, Peek

    (1971) found that moose moved to denser canopies at a snow depth of only 30 cm

    because snow hardness under open canopies made movement more costly.

    Thermal stress is presumed to be a common condition for moose though nearly

    always due to heat, not cold (Schwartz and Renecker 1997, p. 468). Moose have many

    physiological adaptations for low temperatures, including their insulative pelage and

    large size which helps by conserving heat and reducing energy needs in the winter. At the

    northern edge of their distribution, moose may be constrained not by cold temperatures

    but by the absence of forest (Kelsall and Telfer 1974). Lower critical temperatures have

    not been well-tested, although adult moose have been reported to show no visual sign of

    distress at -40C (Schwartz and Renecker 1997, p. 469). Evidence suggests cold stress

    can occur more commonly in calves (at -30C, Renecker et al. 1978) and in late winter as

    a result of tick-induced hair loss (Blyth and Hudson 1987, Glines and Samuel 1989).

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    However, the southern range periphery is thought to be determined largely by

    temperature as moose are reported to be heat-stressed in the winter at 5C, and in the

    summer at 14C, with a panting threshold at 20C (Renecker and Hudson 1986). To avoid

    heat stress moose may seek mature stands with coniferous trees to reduce exposure to

    solar radiation (Schwab and Pitt 1991, Dussault et al. 2004, but see Lowe 2009).

    Because forest stands providing high quality cover for moose are usually

    dominated by closed coniferous canopies, they offer food resources at a lower quantity

    and quality than other forested habitat. Moose generally prefer hardwood browse over

    conifer species (Crte 1989, Conrad 2000) possibly because conifers have elevated levels

    of secondary compounds, such as tannins, that can affect palatability and nutrient

    absorption (Robbins et al. 1987, Bryant et al. 1991). Additionally, the closed canopy of

    cover habitat allows less sunlight to penetrate and less vegetation is able to grow in the

    midstory, diminishing browse quantity. Therefore moose need to leave cover in order to

    better meet their nutritional requirements.

    The concept that moose movements are constrained by the abundance and

    juxtaposition of cover has been well-documented (Coady 1974, Crte 1977, Telfer 1978,

    Welsh et al.1980, Hamilton et al. 1980, Thompson and Vukelich 1981, Eastman and

    Retcey 1987, Peek et al. 1987, Courtois and Beaumont 2002, Dussault et al. 2006). In

    Ontario, Hamilton et al. (1980) found declining trends in winter browse use with

    increasing distance to cover. Although they did not find an upper distance limit from

    cover to feeding locations , 95% of browse use was recorded within 80 m of forested

    cover. Thompson and Vukelich (1981) found that although exceptional distances of 400

    meters were found in early winter, average distance to forested cover was 27 meters.

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    Habitat suitability models for moose commonly include a component related to

    availability or proximity to cover (Allen et al. 1987, Puttock et al. 1996, Naylor et al.

    1999, Dussault et al. 2006), yet these components are often assumed without empirical

    validation, especially in the geographic region in which it is intended to be applied. This

    is the case for moose habitat models in the temperate forests of the Great Lakes Region.

    Two models were created in 1987 by the United States Fish and Wildlife Service

    (USFWS) (Allen et al. 1987). The models operate at different scales with Model I

    estimating carrying capacity at the fine scale of 600 ha (the assumed size of a moose

    home range) and Model II estimating carrying capacity at a coa rser scale of

    approximately 9000 ha (an area presumed large enough to support a population) (Allen et

    al. 1987). In 1999 the Ontario Ministry of Natural Resources (OMNR) created a new

    model based upon components of Model I to aid in forest planning in the Great Lakes

    St. Lawrence Forest (Naylor et al. 1999). The distance to cover as sumptions in this model

    as well as Model I upon which it was based have never been empirically validated,

    although a few partial validations of Model II have occurred (Allen et al.1991, Naylor et

    al. 1992, Puttock et al. 1996, Rempel et al. 1997, Koitzsch 2002). However these

    validations were based on winter aerial survey data or in the la tter case, harvest data, so

    have limited interpretation value. Harvest data are spatially coarse and subject to biases

    (Koitzsch 2002) and aerial surveys provide only a snapshot of moose behaviour because

    they reflect only the winter season and the particular conditions on the day of flight: snow

    depth, snow hardness, temperature, etc. In contrast, GPS collars provide concise,

    frequent, and consistent location data for all seasons, daily periods, and weather

    conditions and therefore are a better tool for model validation.

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    The purpose of this study was to determine if moose select areas closer to cover

    and if the selection depends upon season or habitat. I also was interested in determining

    specific distance parameters: are moose constrained to certain distances from cover , how

    close do they prefer to stay to cover, and do these values differ by season or habitat type

    the moose is in? The second goal of my study was to validate the distance to cover

    assumptions used in OMNRs habitat suitability model for moose. I expected to find that:

    1) overall, moose would select areas close to cover, 2) cover in the dormant season would

    be more important than in the growing season, and 3) moose would be closer to cover

    when they were in early successional stands than when in mature forest, especially during

    the dormant season.

    CHAPTER 2: METHODS

    2.1 Study Area

    This study took place in a 2545 km2 portion on the western side of Algonquin

    Provincial Park located in southeastern Ontario, Canada in the Great Lakes- St. Lawrence

    forest region (45 North, 78 West, Figure 2.1). The 7600 km2 park is comprised of

    shade -tolerant upland hardwoods on poorly drained glacial till, and is intersperse d with

    lakes, wetlands, and mixed and conifer stands in the lower areas (Crins et al. 2008).

    Elevation ranges from 150 - 590 meters above sea level (Friends of Algonquin Park,

    2005) and dominant tree species include sugar maple (Acer saccharum), American beech

    (Fagus grandifolia ), eastern hemlock (Tsuga canadensis), yellow birch (Betula

    alleghaniensis), and red maple (Acer rubrum) (Crins et al. 2008, Appendix A, Table 1).

    Timber harvesting occurs in 78% of the park (56% with water and non-harvestable areas

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    within the harvesting zones excluded) and is comprised largely of selective and

    shelterwood cuts with clearcuts consisting of < 5% (Cumming 2009). Highway 60, a

    major 2-lane route, bisects the southern portion of the park. Recreational human use

    (camping, boating, fishing, hiking) is focused on the major lakes and the few side roads

    within the highway corridor. Interior (logging) roads are not open to public vehicles,

    though backcountry access is available via canoe routes.

    Although Aboriginals harvest moose on the east side of the park, my study area in

    the western side was not subject to moose harvest. During the study period, moose

    population estimates for Wildlife Management Unit 51, the area comprising the majority

    of the park and the entire study area , increased from 2100 in 2006 to 3100 in 2009,

    producing a density of 0.29/km2 and 0.43/km2 , respectively (Steinberg and Francis 2006,

    Steinberg, 2009).

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    Figure 2.1. Study area- Algonquin Provincial Park in southeastern Ontario,

    Canada.

    2.2 Field Methods

    A total of 21 adult female moose (mean age : 4 2 SD years, age range: 1-7) were

    equipped with Lotek 3300L store-on-board GPS collars (Lotek Wireless, Newmarket,

    ON, Canada) in January 2006 and February 2007. Animals were captured via helicopter

    by net-gunning in 2006 (Bighorn Helicopters Inc., Cranbrook, BC, Canada), and by

    darting in 2007 (Heli-horizon Inc., Quebec City, QC, Canada). The anaesthetic applied in

    2007 included a mixture of carfentanil (Wildlife Pharmaceuticals Inc., Ft. Collins,

    Colorado, USA) at approximately 0.0070 mg/kg combined with xylazine hydrochloride

    at approximately 0.2 mg/kg. This drug combination was reversed with naltrexone at

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    approximately 0.7 mg/kg. Radio collars recorded fixes at a two-hour interval and were

    deployed for approximately two years. Survival was monitored usually once or twice per

    month by fixed-wing aircraft and mortalities were investigated from the ground to

    determine cause of death. Collars were removed in March 2008 by Heli-horizon Inc.

    using the same drugging method described above. Field methods were approved by the

    Trent University and Ontario Ministry of Natural Resources Animal Care Committees

    under the guidelines of the Canadian Council on Animal Care.

    GPS collar positional accuracy was believed to be similar to results of an

    accuracy study done with the same collar model in the same study area (Maxie 2009).

    Approximately 1150 fixes were collected in open, hardwood, conifer, and mixed conifer-

    hardwood habitats with an average 3D fix error of 14 2 m SD, 2D fix error of 34 4 m

    SD, and 3D fixes comprising 83.5% of all locations.

    2.3 Habitat Data and Validation

    Habitat analysis was conducted using a Forest Resource Inventory (FRI) map of

    the study area. The FRI is a digital database created from visual interpretation of 1:15,840

    aerial photos, calibrated by ground data, and updated with fire and harvest events every

    five years. It provides stand-level detail including species composition, age, height, and

    stocking (OMNR 2008) with a minimum stand size of 4 ha in the study area. The current

    FRI for the study area was interpreted from photos taken in 1989. Recent timber harvest

    spatial data including harvest type and date was provided by the Algonquin Forestry

    Authority (Huntsville, Ontario, Canada) and used to determine forest age.

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    In 2007, we evaluated species composition accuracy of the FRI in the study area

    by comparison with plot-based field estimates of species composition (Maxie et al. in

    press). In our study area, 25 standard forest units and 8 non-productive forest units were

    derived from the FRI (Elkie et al. 2007). We collapsed similar units into eight study

    groups, including six forest types, wetlands and water. Poor agreement between the FRI

    and field data led us to further collapse forest types to four. These four forest types

    (hemlock, conifer, hardwood, and mixed conifer-hardwood) yielded an overall accuracy

    level of 77%. According to our ground data, hemlock stands were misclassified as

    hardwood 50% of the time (Maxie et al. in press).

    Because of poor map accuracy, I was unable to include the full spectrum of

    standard forest units in my analyses and model validation, and although hemlock may be

    an important source of cover for moose (Forbes and Theberge 1993, Naylor et al, 1999), I

    merged it into the hardwood group because of the frequency of misclassification as

    hardwood. The resulting habitat groups in the analysis consist of three forest types

    (conifer, hardwood, and mixed) and three seral groups (presapling, sapling, and mature)

    yielding an accuracy of 91%. Appendix A, Table 1 illustrates how FRI-based standard

    forest units were combined into the three forest types.

    Seral stage refers to periods of forest succession and is defined according to age

    and FRI-based forest unit. Because some types of forest mature faster than others, the age

    at which a forest advances to the next stage depends on the specific forest type. Appendix

    A, Table 2 illustrates how seral stages were calculated for the habitat groups in relation to

    the FRI forest units that make up each study group. I designed the seral stage age cut-

    offs to reflect those of the majority of FRI forest units within each study group. However,

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    I strayed from the FRI in the way in which I calculated age. The FRI, and consequently

    OMNRs moose model, defines age based on the oldest trees but I defined age according

    to the most recent harvest. Although clear-cutting was not used in this study area, 30-35%

    of the total volume is typically removed in each cut (AFA 2005). Thus, factors important

    to moose such as browse availability and canopy closure more closely reflect younger

    seral stages than older seral stages. Field observations during our habitat accuracy

    exercise supported this belief. Consequently, I have slightly adapted the seral stage

    definitions found in Holloway et al. (2004).

    I defined the presapling seral stage as the youngest categor y of forest where

    vegetation includes herbaceous plants, shrubs, and tree seedlings

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    11

    mixed (11%), and mature conifer (5%). Non-forested areas comprised 22% consisting

    almos t entirely of water and wetland, and were excluded from analysis.

    Though some recent moose studies measured a single level of cover (Dussault et

    al. 2006, Lowe 2009), I considered a gradient of cover in my analyses. I will refer to

    mature conifer as cover because it represents the highest quality cover of my habitat

    groups in both seasons. I additionally considered two lesser cover categories in the

    dormant season, mature forest, and sapling plus, with the latter term referring to any

    forest at sapling stage or older. These lesser cover categories are explained more

    thoroughly in the model validation section of analysis methods.

    2.4 Analyses

    2.4.1 Selection of Cover

    Population Level Selection

    Selection of proximity to cover, which I will refer to as selection of cover, was

    assessed using a type III study design in which use and availability are measured

    separately for each individual instead of as a group (Thomas and Taylor 1990, Manly et

    al. 2002). A Euclidean distance approach was used with distance of forested animal

    locations from cover as use and distance from random forested locations within home

    ranges from cover as available (Conner and Plowman 2001). Spatial analyses were

    performed using ArcInfo (Environmental Systems Research Institute Inc. 1999, 2006)

    and home ranges were created in Home Range Tools for ArcGIS (Rodgers et al. 2007).

    Seasonal home ranges were created using 99% fixed kernels and a referenced

    bandwidth. A fixed kernel density estimator was used instead of an adaptive kernel model

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    because as Kenward and Hodder (1996) suggested, the adaptive model widened the

    kernels in the outlying regions of the home range, effectively over-expanding the

    utilization distribution and leading to an overly liberal area of availability for my

    analysis. The referenced bandwidth smoothing parameter (Worton 1995) was chosen

    because it smoothed all home ranges in a consistent way so that they were comparable. In

    contrast, the least squares cross-validation method (Bowman 1984, Rudemo 1982) failed

    to calculate a smoothing parameter for some home ranges and defaulted to a smaller

    smoothing parameter that resulted in highly under-smoothed utilization distributions

    compared to the rest. Biased cross-validation (Scott and Terrell 1987), the plug-in

    approach (Wand and Jones 1995) and Brownian bridge method (Horne et al. 2007) each

    produced overly conservative (under-smoothed) home ranges for my purpose, effectively

    excluding areas that were likely available to non-territorial and highly mobile species

    such as moose.

    Separate home ranges were estimated for each individual during each season for

    each year (Rettie and Messier 2000). Seasons were based on browse availability and

    defined according to the OMNRs moose habitat suitability model (HSM) with a growing

    season from May 16th to September 30th and a dormant season from October 1st to May

    15th (Naylor et al. 1999). Selection was determined for cover (mature conifer) in both

    seasons and for the lesser cover categories (mature forest and sapling plus) in the dormant

    season.

    To represent availability, random locations were generated within each home

    range using Hawths Analysis Tools (Beyer 2004). Locations were stratified in a 1:1 ratio

    by habitat group according to the animals proportional use in each group. For example,

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    if in a given home range, an animal had 400 locations in mature hardwood, then 400

    random locations were created in mature hardwood within that home range. The distance

    from each random location to the nearest element of each of three levels of cover was

    determined by creating Euclidean distance rasters (10-meter cell size) in ArcGIS Spatial

    Analyst Tools and extracting distance values at the random points. These va lues were

    averaged for each seasonal home range and for each habitat group within each home

    range, producing the expected values under the null hypothesis of no selection. The same

    procedure was applied using the moose locations to calculate the average observed

    distances to cover. Selection ratios of observed mean distances to expected mean

    distances were calculated for each home range and for each habitat group within each

    home range. These ratios were used to determine selection of cover, with ratios

    significantly less than one indicating selection and significantly greater than one

    indicating avoidance (Conner and Plowman 2001, Conner et al. 2003).

    Selection of cover was determined for each season and for each habitat group

    within season using selection ratios as the dependent variable in ANOVAs (Statistica 7.0,

    StatsSoft Inc 2001). The expected value of the null hypothesis was converted from one to

    zero by subtracting a constant of one from the ratio data and consequently an ANOVA

    intercept significantly different than zero would lead to a rejection of the null hypothesis

    (Conner and Plowman 2001). Individual animal was used as a blocking variable to assess

    variation in individuals and account for multiple measures of the same animal because

    seasonal selection ratios were calculated separately for 2-3 consecutive years

    (Chamberlain and Leopold 2000). Individual seasonal home ranges were removed from

    habitat-level analysis if they had fewer than 20 locations in that habitat. This helped

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    avoid spurious selection ratios resulting from insufficient sample sizes and ensure that

    adequate numbers of locations existed for bootstrapping at the home range level

    (described below) (Stine 1985, Boos and Brownie 1989, Zhang et al. 1991).

    Home Range Level Selection

    Because I was interested not only in population level behaviour but also in

    variation within the population, I tested selection of the three types of cover on a home

    range basis, both for the entire home range and for each habitat group within the home

    range. To determine selection for each home range , I bootstrapped the means of both the

    observed and expected distances (Gillingham and Parker 2008) 1000 times to create 95%

    confidence intervals using the statistical package R (R Development Core Team 2006).

    Each of the 1000 replications used 95% of the sample size and was sampled with

    replacement. Bootstrapping was chosen over the parametric standard error of the mean

    because the distance data were not normally distributed and some home ranges had small

    sample sizes (approaching as low as n = 20). Selection of cover was inferred to have

    occurred in a home range if the confidence intervals around the means of observed and

    expected distances did not overlap and the observed mean was lower than the expected

    mean. Because approximately 450 comparisons were made, experiment-wise error likely

    resulted in approximately 5% or 23 false positives, underestimating the outcome of no

    selection by 5% and over-estimating the outcomes of selection and avoidance by

    2.5% each. I considered this when interpreting results.

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    Year Effect

    Environmental conditions affecting habitat use such as temperature and snow

    depth can vary annually so I tested for a year effect for both dormant and growing

    seasons using ANOVA. Because radio-collars were deployed in the middle of the first

    dormant season and removed in the middle of the third dormant season, the three years

    represented different periods and werent comparable. Accordingly, to test for a year

    effect in the dormant season I created separate home ranges and random points to

    calculate selection ratios based only on the overlapping mid-winter period, February 2nd -

    March 6th. The dependent variable in the ANOVAs was selection ratio and individual

    animal was again used as the blocking factor.

    2.4.2 Distance Parameters

    After selection was assessed, three distance parameters were calculated on a home

    range basis and summarized at the population level: median distance, 95-percentile

    distance, and for home ranges where selection occurred, the preference zone was

    determined. Distance parameters were calculated with all habitats combined as well as

    with each habitat separate. Ninety-five percentile distances were calculated to indicate

    how far animals strayed from cover barring temporary excursions and anomalous

    movements. Preference zone is described below.

    The preference zone was defined as the area within which moose preferred to be

    from cover. Visually the edge of this zone is the point in the distance distribution where

    the number of expected locations exceeds the number observed locations (See Figure

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    16

    2.2a for example). To calculate the preference zone edge, observed and expected

    distance-to-cover values for each home range were binned into 100-meter sections. In

    each distance bin, selection ratios were formed using the count of observed locations over

    expected locations with ratios above one indicating selection for the given distance

    category and ratios below one indicating avoidance. These selection ratios and the

    midpoint of their associated distance bins were used in a linear regression as the

    dependent and independent variables, respectively. However, because the relationship

    between selection ratio and distance followed a negative exponential distribution, I log-

    transformed the selection ratios after adding a constant of one. Because selection ratios

    created from a very small number of locations may be overly influential outliers, I

    weighted the regression by the total number of observed and expected locations in each

    distance category. I then solved all the linear regression equations for a selection ratio of

    one (y value of 0.301) to find the edge of the preference zone for each home range where

    selection for cover occurred (See Figure 2.2b for example).

    Determining the preference zone is a new approach and may be more useful than

    traditional measures (such as means) for management and habitat modeling because it

    describes actual animal behaviour. Unlike a simple mean distance, the preference zone

    incorporates both use and expected distributions and is a more valid measure of resource

    selection.

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    Observed Mean = 357Expected Mean = 435

    ObservedExpected

    1 0 0 2 00 300 400 5 0 0 6 00 7 00 8 00 9 00 1 00 0 1 10 0 12 00 1 30 0 1 40 0

    Distance to cover (meters)

    0

    20

    40

    60

    80

    100

    120

    140

    160

    180

    200

    220

    240

    Numberofobservations

    Figure 2.2a. Observed and expected distributions of distance-to-cover from hardwood

    locations for Moose7 in the dormant season of 2006-2007. Preference zone edge can be

    estimated as the general area where the expected values begin to outnumber the observed

    values.

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    Figure 2.2b. Linear regression for Moose7 in the dormant season of 2006-2007 when in

    hardwood stands. The preference zone is the area within 394 meters of cover. A Y value

    of 0.301 is equal to the selection ratio of one.

    2.4.3 Model Validation

    Model Description

    The second goal of the study was to validate the distance to cover parameters in

    OMNRs habitat suitability model (HSM) (Naylor et al. 1999). In the growing season the

    HSM delineates two types of forest stands: those which provide thermal cover and those

    which do not, and it assumes that moose are confined to the area within 1500 meters of

    thermal cover. In the dormant season, the model delineates four types of forest providing

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    various degrees of cover: late winter cover, early winter cover, lateral cover, and no

    cover. It assumes that moose are always constrained to areas within 1600 meters of late

    winter cover. Additionally, when moose are in a stand providing only lateral cover, they

    are assumed to also be constrained to areas within 400 meters of early or late winter

    cover. Three assumptions exist when moose are in a stand that provides no cover. In

    addition to the assumptions above, they are assumed to also be constrained to areas

    within 200 meters ofany level of cover (lateral, early winter, or late winter). HSM

    descriptions of these levels of cover and my corresponding habitat groups are given in

    Table 2.1 and a summary of the distance assumptions is given in Table 2.2. I assigned my

    habitat groups to the models cover categories in the way that most closely reflected the

    majority of FRI forest units within each group (See Appendix A, Table 3). I will refer to

    the 1600-meter assumption as mature conifer, the 400-meter assumption as mature

    forest, and the 200-meter assumption as sapling plus. (These terms refer respectively

    to distance 1, distance 2, and distance 3 in the HSM documentation.)

    The HSM uses the distance assumptions to create grids indicating the range of

    available forested habitat for moose in each season. The full model carrying capacity map

    is a product of three sub-model carrying capacity maps: dormant season, growing season,

    and aquatic feeding. The dormant and gr owing season maps are a product of their season-

    specific range and forage grids. The range grids I am validating in this study directly

    affect the model output because areas that fall outside of the available range result in a

    carrying capacity of zero in the sub-model and subsequently in the final model. I assessed

    the validity of the distance to cover parameters using three methods.

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    Season Cover Category Description Habitat group

    Dormant No cover Height < 3 m Presapling

    Lateral cover Height between 3 and 6 m Sapling

    Early winter cover Height > 6 m with some conifer cover Mature hardwood and mixed

    Late winter cover Height > 10 m and conifer or conifer-dominated mixedwood

    Cover (mature conifer)

    Growing Thermal cover Height = 10 m and lowland conifer,lowland mixed, or lowland hardwood

    Cover (mature conifer)

    Table 2.1. The Ontario Ministry of Natural Resources habitat suitability models

    description of cover categories (Naylor et al. 1999) and my corresponding habitat groups.

    Season Habitat moose is inMature

    conifer

    Mature

    forest

    Sapling

    plusDormant Presapling 1600 m 400 m 200 m

    Sapling 1600 m 400 m --Mature hardwood or mixed 1600 m -- --

    Growing Non-thermal cover forest 1500 m -- --

    Table 2.2. Distance-to-cover assumptions in the Ontario Ministry of Natural Resources

    habitat suitability model for moose and expected 95 percentile distances from moose

    locations to distance categories.

    Validation Method 1

    The first validation method simply involved running the HSM and plotting the

    moose locations over the seasonal range outputs from the model in ArcGIS. Each range

    output is a binary surface of hexagonal parcels with each hectare parcel indicating that it

    is either available habitat (parcel value of 1) or unavailable (parcel value of 0). I

    calculated the percent of all forested moose locations that fell within the forested area

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    deemed unavailable. This helped to determine if the models distance parameters were

    overly conservative (i.e., if moose were willing to travel further from cover than

    assumed). To understand which specific assumptions may be overly conservative, I

    further calculated the percent of moose locations that fell within the assumed unavailable

    area for each habitat group. Inferential statistics could not be used here to compare

    habitat groups because of the lack of variance but the percentage measures were still able

    to indicate effect size.

    Validation Method 2

    Beyond this first simple approach, I was limited in my ability to validate the HSM

    directly as it is based upon the full spectrum of FRI forest units and low map accuracy

    forced me to use combined habitat groups. However, I was able to evaluate how well my

    habitat groups performed in the model. As a second validation method, I substituted the

    HSMs levels of cover with my corresponding habitat groups (Table 2.1) to determine the

    available and unavailable areas of my study area. As in the first method, I calculated

    the percent of all forested moose locations that fell within the unavailable area and

    further calculated the percent of locations in each habitat group that fell within that area.

    I was also able to quantify which of the three distance assumptions were violated for each

    location using the distance values extracted from the Euclidean distance rasters (see

    Analyses: Population Level Selection). Again, inferential statistics could not be used to

    compare habitat groups because of the lack of variance but the percentage measures were

    still able to indicate effect size.

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    Validation Method 3

    The two approaches described above were only able to detect instances where the

    model may be too conservative. To determine if any of the models distance parameters

    are overly liberal (i.e., if moose arent willing to travel as far from cover as assumed), I

    compared the distance assumptions to the 95 percentile of the distribution of distances

    that moose were located from cover. Unlike the first two validation methods that used

    pooled moose locations, this comparison operated at the individual seasonal home range

    level. The validation for the growing season was simple since there is only one distance

    assumption (1500 m from cover). Because the dormant season has multiple assumptions

    depending on the habitat type the animal is in, I calculated 95 percentile distances to three

    groups: my cover group (mature conifer), the three mature forest groups combined

    (mature forest), and the sapling and three mature forest groups combined (sapling

    plus). The 95 percentiles were compared to the HSM distance assumptions (Table 2.2).

    CHAPTER 3: RESULTS

    A total of 94 home ranges (21 individual animals) comprised of 58 dormant

    season and 36 growing season ranges were calculated for the analyses. Growing season

    analyses included 19 individuals because one moose died and one collars data were

    censored from analyses for the growing seasons due to poor fix success. Seasonal home

    range sizes were quite variable, averaging 50 km2 ( 44 SD) in the 7.5-month dormant

    season and 38 km2 ( 23 SD) in the 4.5-month growing season. Overall GPS collar fix

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    success was 91% but many of the missed fixes originated from the one collar that

    malfunctioned during the summers. With this collar removed, fix success averaged 94%

    12% SD.

    3.1 Selection of Cover - Year Effect

    Environmental conditions were similar in the growing seasons but differed in the

    dormant seasons with the second dormant season having less snow depth than the first

    and third (Table 3.1). Home ranges were larger during the second dormant season but this

    increased use of space did not affect distance to cover. Selection of cover was not

    significantly affected by year in either the growing or dormant season (F1,16 = 2.83, p =

    0.11 and F2,34 = 1.484, p = 0.24, respectively). All ANOVA assumptions were met.

    Normality plots are depicted in Appendix B: Figure 1.

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    Season Dates

    Mean DailyMax. Temp

    (C)

    Mean DailyMin. Temp

    (C)Mean

    Temp (C)Mean SnowDepth (cm)

    Growing 2006 May 16 - Sept 30 22 ( 5.6) 8 ( 5.0) 15 ( 4.8) --Growing 2007 23 ( 4.8) 7 ( 4.7) 15 ( 4.2) --

    Historic Normal 21 9 15 --

    Dormant 2005-2006 Oct 1 - May 15 4 ( 9.3) -8 ( 10.1) -2 ( 9.2) 32 ( 27.9)

    Dormant 2006-2007 4 ( 9.2) -8 ( 10.4) -2 ( 9.3) 12 (11.7)

    Dormant 2007-2008 4 ( 9.6) -10 ( 10.5) -3 ( 9.6) 34 ( 12.2)

    Historic Normal 4 -7 -2 28

    Midwinter 2006 Feb 2 - Mar 6 -5 ( 4.7) -19 ( 9.0) -12 ( 6.2) 72 ( 7.4)

    Midwinter 2007 -7 ( 5.4) -21 ( 7.2) -14 ( 5.6) 27 ( 5.1)

    Midwinter 2008 -4 ( 5.1) -19 ( 9.3) -11 ( 6.8) 35 ( 4.5)

    Historic Normal -4 -16 -10 65

    Table 3.1. Mean temperature and snow depths ( SD) for the analysis periods taken from

    Algonquin Park East Gate weather station (Environment Canada 2008). Historic normals

    are averaged from 1971-2000. Year effect analyses were performed using growing season

    and midwinter season. Asterisks indicate snow depths known to influence moose

    movement.

    3.2 Selection of Cover - Home Range Level

    At the home range level, bootstrapping revealed great variability in selection of

    mature conifer cover in each habitat group of each season (Figure 3.1). In the growing

    season the number of home ranges where cover was selected was greater than or equal to

    the number of home ranges where cover was avoided for each habitat group; in the

    dormant season the number of home ranges indicating selection always exceeded the

    number of home ranges indicating avoidance (Figure 3.1a). Selection of the lesser cover

    categories in the dormant season (mature forest and sapling plus) revealed less

    variation. The number of home ranges where cover was selected always outnumbered

    those where cover was avoided but in each case, the most common outcome, no

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    selection, comprised 50% of home ranges (Figure 3.1b). Because approximately 450

    comparisons were made, experiment-wise error likely resulted in 5% or 23 false

    positives, potentially underestimating the outcome of no selection by 5% and over-

    estimating the outcomes of selection and avoidance by 2.5% each. However, this

    adjustment for experiment-wise error does not mask the trends in variance of selection.

    0%

    10%

    20%

    30%

    40%

    50%

    60%

    70%

    Combined

    habitats

    Mature

    Hardwood

    Mature

    Mixed

    Presapling

    Sapling

    Combined

    habitats

    Mature

    Hardwood

    Mature

    Mixed

    Presapling

    Sapling

    n = 36 n = 36 n = 31 n = 15 n = 22 n = 58 n = 54 n = 49 n = 26 n = 40

    Growing Season Dormant Season

    % S

    % NS

    % A

    Figure 3.1a. Variation of selection behaviour at the home range level for mature conifer

    cover. S = selection, A = avoidance, and NS = no selection. N refers to the number of

    home ranges in each category.

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    0%

    10%

    20%

    30%

    40%

    50%

    60%

    Sapling plus Mature forest Mature forest

    Presapling Presapling Sapling

    n = 26 n = 26 n = 40

    % S

    % NS

    % A

    Figure 3.1b. Variation of selection behaviour at the home range level for the lesser cover

    categories associated with presapling and sapling forest in the dormant season (mature

    forest and sapling plus). S = selection, A = avoidance, and NS = no selection. N refers

    to the number of home ranges in each category.

    3.3 Population Level Seasonal Results

    In the growing season the intercept of the ANOVA indicated no selection for

    proximity of cover, meaning that at the population level, moose tended to be the same

    distance from cover within their home ranges as expected by chance (F1,17 = 0.908, p =

    0.354, selection ratio = 1.00 0.23 SD) (Table 3.2a). However, moose ID was a

    significant source of variation (F18,17 = 7.339, p < 0.01) and bootstrapping revealed that in

    only 19% of home ranges did moose show no selection with moose in 42% of home

    ranges showing selection, and 39% showing avoidance. The average median distance

    animals were from cover was 470 meters and 95% of the locations were within 1144

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    meters of cover. Those figures for just the moose that selected cover (n = 15 of 36) were

    321 and 991 meters, respectively (Table 3.3). The average preference zone edge was 621

    meters.

    In the dormant season the intercept of the ANOVA indicated a marginally

    significant trend in selection of cover at the population level (F1,37 = 3.176, p = 0.083,

    0.93 0.21 SD) (Table 3.2a), with moose ID also being marginally significant (F20,37 =

    1.715, p = 0.076). The average median distance animals were from cover was 427 meters

    and 95% of the locations were within 1135 meters. When just considering those moose

    that selected cover (n = 36 of 58), those figures were 304 and 1014 meters, respectively

    (Table 3.3). The average preference zone edge was 532 meters. All ANOVA assumptions

    were met. Normality plots associated with these ANOVAs are shown in Appendix B,

    Figure 2.

    3.4 Population Level- Habitat Results

    During the growing season, moose as a whole did not significantly select or avoid

    proximity to cover when they were in any of the habitat groups, although there was a

    marginally significant avoidance when moose were in saplings(F1,10 = 3.747, p = 0.082,1.407 1.04 SD) (Table 3.2a). Distance parameters for all home ranges, those selecting

    cover, and those avoiding cover are presented in Table 3.3. Figures 3.2a-c illustrate

    distance parameters for home ranges showing selection for cover. Depending upon the

    habitat group, selection of cover occurred in 32 to 46% of growing season home ranges.

    In the dormant season, moose as a whole did not significantly select or avoid

    proximity to cover when they were in any of the habitat groups, although there was

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    marginally significant selection in mature hardwoods (F1,34 = 3.919, p = 0.056, 0.937

    0.29 SD) (Table 3.2a). The preference zone edge was significantly lower in mature

    hardwood than in presapling stands (Figure 3.2c). The proportion of dormant season

    home ranges in which selection of cover occurred ranged from 38 to 48% depending

    upon the habitat group. For every habitat group in this season, proportionately more

    individuals selected cover and distance parameters were consistently lower, indicating

    that cover is more important in the dormant season than the growing season. All ANOVA

    assumptions were met. Normality plots at the habitat group level for both seasons are

    shown in Appendix B, Figure 3.

    In the dormant season I also assessed selection and distance parameters of the two

    lesser categories of cover, mature forest and sapling plus. When in young forest,

    moose as a whole did not select areas closer to any lesser type of cover (Table 3.2b).

    Distance parameters for all home ranges, those selecting cover, and those avoiding cover

    are presented in Table 3.4a-b. Figures 3.3a-c illustrate distance parameters for home

    ranges that showed selection for cover. All ANOVA assumptions were met. Normality

    plots are shown in Appendix B, Figure 4.

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    A.

    Season Habitat Group ANOVA resultsSelection

    Ratio SD

    Growing Combined F1,17 = 0.908, p = 0.354 1.003 0.234

    Hardwood F1,16 = 0.153, p = 0.700 0.989 0.325

    Mixed F1,14 = 0.122, p = 0.732 1.010 0.321

    Presapling F1,7 = 1.305, p = 0.291 0.999 0.280

    Sapling* F1,10 = 3.747, p = 0.082 1.407 1.042

    Dormant Combined* F1,37 = 3.176, p = 0.083 0.934 0.212

    Hardwood* F1,34 = 3.919, p = 0.056 0.937 0.288

    Mixed F1,30 = 2.002, p = 0.167 0.901 0.287

    Presapling F1,16 = 0.219, p = 0.646 1.065 0.456

    Sapling F1,23 = 1.814, p = 0.191 1.031 0.486

    B.

    Habitat Cover category ANOVA resultsSelection

    Ratio SD

    Presapling Sapling plus F1,16 = 0.007, p = 0.936 0.955 0.107Presapling Mature forest F

    1,16= 0.484, p = 0.497 1.018 0.093

    Sapling Mature forest F1,24 = 2.645, p = 0.117 0.935 0.105

    Table 3.2. Results of habitat group level mature conifer cover selection ANOVAs (A)

    and selection of the lesser cover categories associated with presapling and sapling in the

    dormant season. Asterisks indicate marginal significance. Sapling plus refers to the

    combination of any sapling or mature forest (B).

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    Season Habitat Group n

    %

    S

    %

    NS

    %

    A

    All home ranges Home ranges selecting cover Home ranges avoiding cover

    Observed Expected Observed Expected Observed Expected

    Median CI Median CI Median CI Median CI Median CI Median CI

    GrowingSeason

    Combined

    habitats 36 42 19 39 470 82 446 63 321 43 408 56 545 94 411 68

    MatureHardwood 36 46 29 26 407 66 393 4 0 246 54 362 60 596 79 380 68

    Mature Mixed 31 35 39 26 448 82 395 47 277 65 395 90 638 191 354 103

    Presapling 15 40 20 40 589 160 597 148 561 260 700 153 558 125 443 117

    Sapling 22 32 36 32 531 168 497 165 323 95 456 96 695 217 458 239

    DormantSeason

    Combinedhabitats 58 62 14 24 427 81 448 72 304 50 396 54 749 235 601 248

    MatureHardwood 54 48 31 20 335 56 343 29 217 32 327 41 584 164 351 40

    Mature Mixed 49 39 41 20 350 56 376 29 212 40 347 44 581 150 444 76

    Presapling 26 38 31 31 565 99 546 83 436 104 648 151 822 174 480 121

    Sapling 40 40 30 30 503 136 461 118 242 99 374 131 832 314 523 319

    Table 3.3a. Moose median observed and expected distances to cover plus 95% confidence intervals (in meters) by season and habitat

    group for all home ranges, those where cover was selected, and those where cover was avoided. N refers to the number of home

    ranges in each group. %S = % home ranges showing selection, %NS = % showing no selection, and %A = % showing avoidance.

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    All home rangesHome ranges

    selecting coverHome ranges

    avoiding cover

    Observed Expected Observed Expected Observed Expected

    Season Habitat Group n%S

    %NS

    %A 95% CI 95% CI 95% CI 95% CI 95% CI 95% CI

    Combinedhabitats 36 42 19 39 1144 154 1225 149 991 143 1152 113 1149 190 1106 136

    Mature Hardwood 36 46 29 26 1000 120 1079 98 856 179 1067 151 1188 213 1060 196

    Mature Mixed 31 35 39 26 932 118 1044 122 759 86 1127 143 1034 246 995 235

    Presapling 15 40 20 40 1135 196 1328 298 1132 284 1535 385 970 172 926 222

    GrowingSeason

    Sapling 22 32 36 32 1171 291 945 269 943 379 1243 206 1364 421 1013 454

    Combinedhabitats 58 62 14 24 1135 117 1247 116 1014 130 1203 141 1496 272 1451 276

    Mature Hardwood 54 48 31 20 943 81 1054 72 760 78 988 97 1223 118 1107 146

    Mature Mixed 49 39 41 20 911 94 1061 88 785 152 1048 140 1197 175 1111 213

    Presapling 26 38 31 31 1062 134 1223 154 1059 263 1394 264 1136 179 1050 177

    DormantSeason

    Sapling 40 40 30 30 1132 216 1219 224 837 314 1134 367 1383 438 1309 461

    Table 3.3b. Moose observed and expected ninety-five percentile distances plus 95% confidence intervals (in meters) to cover by

    season and habitat for all home ranges, those where cover was selected, and those where cover was avoided. N refers to the number of

    home ranges in each group. %S = % home ranges showing selection, %NS = % showing no selection, and %A = % showing

    avoidance.

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    All home ranges Home ranges selecting cover Home ranges avoiding cover

    Observed Expected Observed Expected Observed ExpectedHabitatGroup

    CoverCategory n

    %S

    %NS

    %A Median CI Median CI Median CI Median CI Median CI Median CI

    Presapling Sapling plus 26 35 50 15 115 16 123 16 119 29 157 20 131 63 93 49

    Presapling Mature forest 26 35 50 15 189 37 183 32 194 54 224 48 274 148 178 118

    Sapling Mature forest 40 30 50 20 147 38 149 37 131 60 194 83 262 73 173 64

    Table 3.4a. Moose observed and expected median distances plus 95% confidence intervals (in meters) to lesser cover categories

    associated with presapling and sapling in the dormant season for all home ranges, those where cover was selected, and those where

    cover was avoided. N refers to the number of home ranges in each group. Sapling plus refers to the combination of any sapling or

    mature forest.

    All home ranges Home ranges selecting cover Home ranges avoiding cover

    Observed Expected Observed Expected Obser ved ExpectedHabitat

    Group

    Cover

    Category n%

    S

    %

    NS

    %

    A 95% CI 95% CI 95% CI 95% CI 95% CI 95% CI

    Presapling Sapling plus 26 35 50 15 310 33 361 45 312 42 456 62 341 161 293 163

    Presapling Mature forest 26 35 50 15 432 56 461 61 435 87 521 87 495 212 513 254

    Sapling Matu re forest 40 30 50 20 396 88 412 85 409 158 541 179 654 189 541 136

    Table 3.4b. Moose observed and expected ninety-five percentile distances plus 95% confidence intervals (in meters) to lesser cover

    categories associated with presapling and sapling in the dormant season for all home ranges, those where cover was selected, and

    those where cover was avoided. N refers to the number of home ranges in each group. Sapling plus refers to the combination of any

    sapling or mature forest.

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    Figure 3.2a. Moose observed (o) and expected (e) average median distances to cover (

    95% CI) of home ranges where selection of cover occurred for each season and habitat

    group. %S is the percent of all home ranges where cover was selected and n is the

    number of home ranges where cover was selected.

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    Figure 3.2b. Moose observed (o) and expected (e) average 95 percentile distances to

    cover ( 95% CI) of home ranges where selection of cover occurred for each season and

    habitat group. %S is the percent of all home ranges where cover was selected and n is the

    number of home ranges where cover was selected.

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    0

    200

    400

    600

    800

    1000

    1200

    1400

    1600

    1800

    Combinedhabitats

    Hardwood Mixed Presapling Sapling Combinedhabitats

    Hardwood Mixed Presapling Sapling

    % S = 42 % S = 46 % S = 35 % S = 40 % S = 32 % S = 62 % S = 48 % S = 39 % S = 38 % S = 40

    n = 15 n = 15 n = 11 n = 6 n = 7 n =36 n = 26 n = 19 n = 10 n = 16

    Growing Season Dormant Season

    Meters

    Figure 3.2c. Moose average preference zones for cover ( 95% CI) for each season and

    habitat group. %S is the percent of all home ranges where cover was selected and n is the

    number of home ranges where cover was selected.

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    Figure 3.3a. Moose observed (o) and expected (e) average median distances ( 95% CI)

    to lesser cover categories associated with presapling and sapling forest in the dormant

    season for home ranges where selection of cover occurred. Sapling plus refers to the

    combination of any sapling or mature forest. %S is the percent of all home ranges where

    cover was selected and n is the number of home ranges where cover was selected.

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    Figure 3.3b. Moose observed (o) and expected (e) average 95 percentile distances ( 95%

    CI) to lesser cover categories associated with presapling and sapling forest in the dormant

    season for home ranges where selection of cover occurred. Sapling plus refers to the

    combination of any sapling or mature forest. %S is the percent of all home ranges where

    cover was selected and n is the number of home ranges where cover was selected.

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    0

    50

    100

    150

    200

    250

    300

    350

    Sapling plus Mature forest Mature forest

    Presapling Presapling Sapling

    % S = 35 % S = 35 % S = 30

    n = 9 n = 9 n = 12

    Meters

    Figure 3.3c. Moose preference zone edge ( 95% CI) in relation to lesser cover

    categories associa ted with presapling and sapling in the dormant season. Sapling plus

    refers to the combination of any sapling or mature forest. %S is the percent of all home

    ranges where cover was selected and n is the number of home ranges where cover was

    selected.

    3.5 Model Validation

    3.5.1 Validation Method 1

    For the first validation approach I simply plotted the moose locations on top of the

    habitat availability range grids from the HSM. The growing season range grid designated

    40% of the study area, mainly in the greater Highway 60 corridor, as unavailable habitat.

    The large unavailable area is a result of the limited forest types that the model assumes

    to provide thermal cover. Specifically, thermal cover as defined by the HSM model

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    composed less than 2% of the study area and 49% of all forested moose locations fell in

    the unavailable area, including one animals entire home range (Figure 3.4a).

    To find out if violations occurred more often in any particular habitat group, I

    compared the proportion of points that violated the assumptions to points that did not for

    each habitat group. If moose were equally likely to violate the HSM assumptions in any

    given habitat, then I would expect approximately the same proportion of locations (49%

    5%) within each habitat group to fall within area deemed unavailable. This was the case

    for all habitat groups except for the sapling group where 63% of the locations were in

    violation of the distance assumptions , a magnitude of 14 percentage points more than the

    expected 49%. These violations occurred in locations of all 12 of the moose that used the

    habitat group. In all other habitat groups, violation proportions were within 5 percentage

    points of the expected 49% and therefore less likely to be of particular interest.

    The dormant season range grid designated only 1% of the study area as

    unavailable and virtually no forested moose locations (0.1%) occurred within this limited

    area (Figure 3.4b).

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    Figure 3.4a. Map of the growing season range calculated in OMNRs moose habitat

    suitability model and the seasonal moose locations falling in and outside of the

    available habitat in the southwestern portion of Algonquin Provincial Park, Ontario,

    Canada. Distance assumption violations occurred in 49% of moose locations.

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    Figure 3.4b. Map of the dormant season range calculated in OMNRs moose habitat

    suitability model and the seasonal moose locations falling in and outside of the

    available habitat in the southwestern portion of Algonquin Provincial Park, Ontario,

    Canada. Distance assumption violations occurred in 0.1% of moose locations.

    3.5.2 Validation Method 2

    The second method of validation was independent of the HSM; I substituted my

    habitat groups into the models groups that represent various degrees of cover: no cover,

    lateral cover, early winter cover, and late winter cover (Table 2.1). My adapted grids

    designated 8% of the study area as unavailable in the growing season and 10% as

    unavailable in the dormant season (Figures 3.5a -b).

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    Figure 3.5a. Map of the growing season range created from my adapted model and the

    seasonal moose locations falling in and outside of the available habitat in the

    southwestern portion of Algonquin Provincial Park, Ontario, Canada. Distance

    assumption violations occurred in 3% of moose locations.

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    Figure 3.5b. Map of the dormant season range created from my adapted model and the

    seasonal moose locations falling in and outside of the available habitat in the

    southwestern portion of Algonquin Provincial Park, Ontario, Canada. Distance

    assumption violations occurred in 12% of moose locations.

    Distance assumption violations in the growing season were minimal with only 3%

    of forested moose locations falling within the area assumed to be unavailable. To find out

    if these violations occurred more often in any particular habitat group, I compared the

    proportion of points that violated the assumptions to points that did not for each habitat

    group and expected the same proportion of locations (3%) within each habitat group to

    fall within the area deemed unavailable. Instead, 19% of sapling locations were in

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    violation of the distance assumption, though these violations only occurred among three

    of 12 animals. Violations occurring in the other habitat groups were all minor at 1%, 1%,

    and 3% for presapling, mature hardwood, and mature mixed, respectively and therefore

    not of particular interest.

    In the dormant season distance assumption violations occurred in 12% of forested

    moose locations. Again, if violations occurred equally in the habitat groups, I would

    expect the same proportion of locations (12%) within each habitat group to fall within the

    area deemed unavailable. In contrast 41 and 31% of the locations in presapling and

    sapling, respectively, were in violation and locations in mature hardwood and mature

    mixed forest were only in violation 0.3 and 0.5%, respectively. The vast majority of

    violations that occurred in young forest were violations of the distance assumptions of

    lesser cover: i.e., the animals were further than 200 meters from all types of forest

    providing cover (sapling plus) or further than 400 meters from all types of mature

    forest (Table 3.5).

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    Assumption Violations*

    Habitat group n% of pointsin violation n

    Matureconifer n

    Matureforest n

    Saplingplus n

    Presapling 10 41% 10 0.03% 2 47% 10 77% 10Sapling 16 31% 9 48% 4 74% 8 -- --Mature hardwood 20 0% 0 -- - -- -- -- --

    Mature mixed 19 1% 5 100% 5 -- -- -- --

    Table 3.5. Breakdown of distance assumption violations for the dormant season. The

    mature conifer assumption refers to points greater than 1600 meters from cover.

    Mature forest assumption refers to points greater than 400 meters from all mature

    habitat groups (hardwood, mixed, and cover). Sapling plus assumption refers to points

    greater than 200 meters from saplings and all mature habitat groups combined. N refers

    to the number of animals associated with each result. * The sum of distance assumption

    violations 1 - 3 may exceed 100% in a given habitat group because some points violated

    more than one assumption.

    3.5.3 Validation Method 3

    The third validation method compared the distance assumptions to the 95

    percentile distances of moose locations from cover (see Tables 3.3b and 3.4b). In all

    instances, moose at the population level did not significantly select areas closer to cover,

    meaning the 95 percentile distances merely reflect what was available within the home

    ranges. Therefore, these distances dont necessarily reflect the true limits for the moose

    population as a whole, but they at least represent a minimum threshold of the distance

    moose are willing to travel from cover. All of the 95 percentile distances were below the

    model assumptions except for presapling stands in the dormant season, where 95% of the

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    moose locations were within 310 (33) meters from any type of cover (sapling plus)

    instead of the HSM-assumed 200 meters.

    CHAPTER 4: DISCUSSION

    4.1 Selection of Cover

    4.1.1 Prediction 1: Overall, moose will select areas close to cover

    Overall, I found that cover selection by moose in Algonquin was not as strong as I

    had hypothesized but I did note a high degree of variation in selection ratios among home

    ranges. If distance to cover is not an important factor for moose, then I would expect

    individuals in the majority of home ranges to show no selection. Instead the population-

    level result of no selection was caused by more of a bimodal distribution of selection

    behaviour, with the number of home ranges where cover was selected cancelled out by

    home ranges where cover was avoided. This was most evident in the selection of mature

    conifer cover (Figure 3.1a). The variance in selection behaviour was not due to a year

    effect nor was it fully explained by an animal effect, as several animals switched their

    selection behaviour during the study. In the dormant season, 65% of individuals switched

    selection behaviour during the three years and 24% switched behaviour during the two

    growing season years. I suspect that some of this variation could be explained by calf

    presence, with encumbered females staying closer to cover while unencumbered moose

    are able to forage more freely away from cover. The belief that calf presence influences

    cow movements with respect to cover is fairly well documented in the literature. In

    southwestern Montana, bulls and cows without calves made greater use of open areas

    than cows with calves (Peek 1962). In northeastern Ontario, cows with calves made

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    much more use of areas abundant with cover and forage than open areas (Thompson and

    Vukelich 1981). In Quebec, Dussault et al. (2005) found cows with calves to have a

    higher preference for 10-year old mixed and deciduous stands and mature conifer stands,

    habitats that provide the most concealment cover, indicating a focus on protection from

    predators. However, to my knowledge, no study has fully examined habitat selection in

    relation to specific distance to cover and the needs of calves. These distance parameters

    would be valuable for modeling and management purposes.

    Factors causing moose to choose areas far from cover are less apparent but it may

    be a behavioural response to those selecting cover. Moose, like most ungulates are

    polygynous and tend to sexually segregate during many parts of the year (Bleich et al.

    1997, Bowyer 1984, Bowyer et al. 1996, 2001, Kie and Bowyer 1999, Miller and

    Litvaitis 1992, Miquelle et al. 1992). In a winter habitat management study, Bowyer et al.

    (2001) crushed areas of old-growth willow to provide more accessible forage and found

    the crushed areas to be beneficial only to males, as females with calves were deterred by

    the lack of cover. The authors consequently recommended that the sexes be treated as

    separate species in terms of habitat management and emphasized the importance of

    predation risk in management intended to aid females. Kie and Bowyer (1999) had the

    same recommendation for white-tailed deer. My study revealed variation in selection of

    cover even within females. However, this same mechanism may have been at work as

    Dussault et al. (2005) found habitat use of unencumbered females to more closely

    resemble that of males than that of females with calves.

    This spatial segregation may be a behavioural response of two potential processes.

    Moose may be employing a density-dependent foraging strategy, in which unencumbered

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    individuals choose to forage in lower quality feeding areas (areas far from cover) to avoid

    intraspecific competition with the encumbered cows. A second factor affecting this

    spatial segregation could be a predator avoidance strategy, in which individuals avoid

    aggregating to reduce chances of detection by predators, a common strategy among

    ungulates of forested habitats where concealment options exist (Kie 1999).

    4.1.2 Prediction 2: Cover will be more important in the dormant season than in the

    growing season

    I hypothesized that moose would show greater select ion for cover in the dormant

    season than the growing season and found evidence supporting this. In the dormant

    season the percent of home ranges where cover was selected was higher than in the

    growing season. In addition all median and 95-percentile distances were lower in the

    dormant season than in the growing season. These results are not surprising because the

    difference between cover and non-cover is more distinct when dec iduous foliage is

    absent. In the dormant season, deciduous trees provide considerably less concealment

    cover and thermal protection than they do in the growing season. Additionally, movement

    in the dormant season through stands dominated by deciduous species becomes more

    energetically costly as snow accumulates. These phenomena are compounded as winter

    progresses and ungulates are weakened by a less nutritious diet (Schwartz et al. 1987,

    1988, Renecker and Hudson 1989, Schwartz 1992), making proximity to cover in the

    dormant season even more important relative to the growing season.

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    4.1.3 Prediction 3: Moose will be closer to cover when in early successional stands than

    when in mature stands, especially during the dormant season.

    At the habitat level in the dormant season, I expected that distance to cover would

    be least important to moose when they were in mature stands , especially mature mixed

    stands, since mature forest most closely resembles cover. Also a large body of literature

    supports the belief that browsing in open areas is focused at edges with stands providing

    cover (Neu et al. 1974, Bangs et al. 1985, Allen et al. 1991, Dussault et al. 2006).

    However, my data showed more support for the opposite effect, with selection ratios and

    distance parameters tending to be lower in mature forest than in young forest. Perhaps

    young forest provided such a high quality feeding area in my study that they were

    important to moose regardless of distance to protective cover. This apparent non-

    selection for proximity to cover in young forest could also be an artifact of the spatial

    patterns in my study area. Young stands (i.e. timber harvests) were typically greater than

    500 m from cover, possibly too far to influence space use within those habitats.

    Repeatable studies in other locations would help clarify these patterns and mechanisms.

    4.2 Model Validation

    All three of my validation approaches indicated that the model could be

    improved, with the first approach illustrating this most clearly. In Algonquin the biggest

    apparent weakness in the full HSM is the growing season thermal cover assumptions that

    designated a large area, mostly in the greater Highway 60 corridor, as unavailable to

    moose. This unavailable designation gets carried through the growing season sub-model

    and further to the full model, resulting in a predicted carrying capacity in that area of zero

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    moose/km2. The nearly 50% of moose locations, including all locations of an individual,

    that fell in this unavailable area provides strong evidence that the model is flawed.

    Indeed, a kriged map based on OMNRs winter aerial surveys predicted the area to have a

    density between 0.4 and 0.5 moose/km2 (Loveless 2009) and the two other sub-models,

    dormant season carrying capacity and aquatic feeding carrying capacity, predicted this

    area to be capable of supporting between 0.6 and 0.8 moose/km2. The estimates of these

    two sub-models better agree with aerial survey data than the growing season sub-model,

    especially considering that estimations of carrying capacity (in the HSM) will be

    somewhat higher than estimates of density (from aerial surveys). It is apparent in our

    study area that the parameters related to thermal cover are too conservative, biasing low

    the estimate of available growing season area, growing season carrying capacity, and

    finally total carrying capacity.

    There are a few possible reasons why the thermal cover assumptions in the

    growing season are flawed. One possibility is that moose are willing to feed much further

    from thermal cover than the 1500 m presently assumed. Although this could be true, the

    HSMs unavailable area is occupied by entire home ranges of a relatively high density of

    moose that have no access to thermal cover as defined by the model. Hence it is more

    likely that either 1) moose dont need thermal cover at all (Lowe 2009) or 2) that they are

    using other habitats as thermal cover. It is unlikely that moose dont need thermal cover

    because during the study period, ambient summer temperature exceeded the presumed

    critical temperature for moose 65% of the time and the panting threshold 31% of the time

    (Lowe 2009). The most plausible answer is that the forest types that comprise thermal

    cover in the model are too restrictive. The model assumes that thermal cover is provided

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    only by four types of forest: cedar, lowland conifer, lowland