Conservation of BIODIVERSITY

Preview:

DESCRIPTION

Conservation of BIODIVERSITY. Biodiversity can be assessed and conserved at several levels: Molecular/Genetic (rare genes and alleles) Population Species Assemblage Ecosystem Global. BIODIVERSITY. Molecular/genetic is the level at which natural selection and evolution occurs - PowerPoint PPT Presentation

Citation preview

Conservation of BIODIVERSITY

• Biodiversity can be assessed and conserved at several levels: – Molecular/Genetic (rare genes and alleles) – Population – Species – Assemblage – Ecosystem – Global

BIODIVERSITY

• Molecular/genetic is the level at which natural selection and evolution occurs – Loss of genetic diversity impedes “adaptability” – Loss of populations similarly handicaps a species’

chance of surviving uncertain circumstances in the future.

Loss of BiodiversityLoss of Biodiversity

• Many reasons, often confounded

• Historic extinctions – p/t extinction (250 mya) – k/t extinction (65 mya)

• Holocene extinctions: 10,000 years ago to present

EXTINCTIONEXTINCTION

• “Given evolutionary turnover, extinction is inevitable. Like death for the individual, nothing is more certain in the future of a species than its ultimate removal.”

P. Martin and R. G.Klein IN Quarternary Extinctions:

A Prehistoric Revolution

1984

Current ExtinctionsCurrent Extinctions

• Current biodiversity crisis – Human mediated

• Correlated with Homo sapiens expanding range and density

• Ever-quickening rate of extinctions

– Has led to increase of 1000 – 10,000% above the rate of background extinctions

Current ExtinctionsCurrent Extinctions

• Current biodiversity crisis – Before 1800

• Islands: many unique island assemblages decimated – Gigantic flightless birds

– Gigantic tortoises

– Dwarf elephants/hippos

• Continents: severe extinctions among megafauna – North american mammals

– South american marsupials

Current ExtinctionsCurrent Extinctions

• After 1800: – Extinctions on islands continue

• Birds, endemic mammals, reptiles

– Extinctions among smaller continental fauna increase in pace

• Habitat destruction/conversion • Unregulated trade • Bounties on “undesirable” species

Conservation of HerpetofaunaConservation of Herpetofauna

• Amphibians and reptiles face many of the same threats that face other non-human organisms: – Habitat modification and destruction – Introduction of exotic species – Pollution – Commercial exploitation – Traditional and modern medicine – Pets – Research and teaching– Traffic mortality– Persecution

Habitat modification and Habitat modification and destructiondestruction

• The most significant problem • Absolutely correlated with increasing human population

size • Extensive and worldwide; all biomes, but tropical

rainforests hit hardest • “At the current rate of deforestation, within 30 years

there will remain neither extensive tropical forests, nor their endemic amphibian and reptile fauna”

from Pough et al. 2001

1) Habitat destruction

a) Deforestation of tropical forests

b) Destruction of coral reef ecosystems

c) Wetland alteration for development

d) Temperate regions altered for agriculture

e) Habitat fragmentation

Habitat modification and Habitat modification and destructiondestruction

• >95% of central California’s marshes were drained and converted before 1900. – Rana aurora draytonii (California red-legged

frog), once California’s most common frog, all but disappeared

– Thamnophis gigas (giant garter snake), slowly declined, now almost extinct

Habitat destruction:

Habitat modification and Habitat modification and destructiondestruction

• In Florida, habitat conversion may have been responsible for a decline in Ambystoma cingulatum – 200-300 per night between 1970-1972 – <1 per night after habitat conversion in 1990-

1992

• Anniella pulchra declines correlated with introduced plant spp.

Habitat modification and Habitat modification and destructiondestruction

• Often works in tandem with weedy or introduced species – In Arizona, alteration of hydrologic regime enables

crayfish, game fish and bullfrogs to persist where they otherwise couldn’t

– Argentine ants expanding range into U.S. deserts by utilizing lawns and other landscaping features. Decline in Phrynosoma coronatum and P. cornutum correlated with spread of fire ants

Habitat Fragmentation

Introduced speciesIntroduced species• Declines (and extinctions) in many island species

attributable to introduced exotics – Dogs and cats: Cyclura carinata in Caicos Islands – Cats: Brachylophus iguanas in the South Pacific – Goats: Crotalus unicolor on Aruba Island – Sheep, goats, rats: Sphenodon in New Zealand – Introduced fish in California’s high elevation lakes:

Rana muscosa and Thamnophis spp. – Fire ants impacting Texas horned lizard (P. cornutum)

and Coast horned lizard (P. coronutum)– Small Indian Mongoose: 7 species of reptile and

amphibian from Puerto Rico

Introduced Species: HerpsIntroduced Species: Herps

• Bullfrog: western U.S, C. and S. America, England, France, Asia, many other places

• Boiga irregularis: Guam – Wiping out geckos and skinks (all birds, bats,

many small mammals already gone)

• Introduced herp assemblages at ports-of-call

Introduced Herps by State Introduced Herps by State (Simberloff et al. 1996)(Simberloff et al. 1996)

05

10152025303540

PollutionPollution

– Acid rain: • Ambystoma tigrinum in the Rocky Mountains • Bufo calamita in Britain

– Selenium/agriculture runoff: • Thamnophis gigas in California’s Central Valley

– Pesticide wafting: Rana and Bufo spp. in the Sierra Nevada

PollutionPollution

• Solid Waste: marine turtles

• PCB’s: effect endocrine systems of aquatic frogs and turtles

• Acidic runoff from mines: Rana tarahumarae in Arizona

Pollution • Biomagnification

– The increase in the concentration of bioaccumulated toxic chemicals in organisms higher on the food chain due to preferential storage of the toxic chemical in edible body parts

• There is abundant evidence that some carnivores at the ends of longer food chains (crocodiles, alligators, snakes) suffered serious declines in fecundity and hence in population size because of this phenomenon

Anthropogenic eutrophication

• Nutrients released, triggering chain of events

Directly Impacts aquatic turtle, alligator, snake populations

Over-harvesting

Commercial collecting: FoodCommercial collecting: Food

• Frogs: U.S., Europe, SE Aisa, Africa – Late 1800’s: extreme

decline in availability of California red-legged frogs partially attributable to collecting pressure

– 1976- 2.5 million KG frog legs imported into U.S.

– Annual consumption in France: 2.7-3.6 million KG frog legs

Commercial collecting: FoodCommercial collecting: Food

• Declines in Iguana iguana and Ctenosaura similis

• Monitors, pythons, tortoises, sea turtles

Commercial collecting: SE Commercial collecting: SE Asian Turtle CrisisAsian Turtle Crisis

• 12 million turtles sold per year in China’s food markets

• China’s and Vietnam’s turtle populations depleted: now imported from all around the world, including the U.S.

• Many of China’s turtles were only known from the food markets: no natural history or distribution information available

• Many of those turtles have not been seen in markets for years

Commercial collecting: SE Commercial collecting: SE Asian Turtle CrisisAsian Turtle Crisis

• Low reproductive rate combined with great importance placed on age of turtle has dire consequences for natural populations

The bycatch problem:

Commercial exploitation for Commercial exploitation for skinsskins

• Civil war: Thousands of American alligators killed for skins

• Legal importation of 304,189 pairs of Boa constrictor boots and 176,204 pairs of Python reticulatus into U.S in 1981 (all harvested from the wild)

• >1 million crocodile skins per year from 1980 to 1985

• >12 million tegu skins during same period

Commercial exploitation for Commercial exploitation for skinsskins

• Most species harvested for skins are long-lived

• Until recently all have been harvested from the wild

• Some progress being made to establish farms for commercially important species

• The vast majority of skins are still collected from wild animals

Traditional and Modern Traditional and Modern MedicineMedicine

• Bufo alvarius and Phyllomedusa bicolor used in shamanistic rituals

• Snake venom used in antivenin and anticoagulant drugs

• Batrachotoxin used in research to probe for voltage-sensitive sodium channels

• Rattlesnake “shaker muscle” used in physiology studies

PetsPets

• In Florida, 119,831 herps removed from the wild between 1990-1992

• 74,000 box turtles exported as pets between 1992-1994

• Habitat destruction often accompanies collecting for pets

• Very little record kept regarding #’s of animals collected as pets from the wild

Pet trade• “In the United States, the retail trade in live reptiles,

amphibians, and related products is worth a minimum of two billion dollars annually” -Joseph Franke MS and Teresa Telecky

• If you wish a reptile as pet make sure you are dealing with dealer that can be trusted. Find out where the animals come from

ResearchResearch

• For scientific collections: usually very small impact

• For bio and medical training – In early 1970’s 15 million leopard frogs

collected from the wild – 1970-1971: 10 tons of leopard frogs collected

from one western state – 250 lbs collected 4 years later

Traffic Mortality – Roadkill!

Increases mortality of individuals and also decreases gene flow

Matthew Aresco, a 4th year PhD student in the Department of Biological Science at Florida State University built a temporary fence to divert turtles (and other wildlife, > 41 species) away from the road and into a culvert that joined the two lakes. Over the past 2.5 years he has monitored the temporary fence at least twice per day and maintained it at his personal expense (at least $2000 out-of-pocket).

Species such as frogs, snapping turtles, large softshell turtles, alligators, and most mammals can climb over this low fence. The fence only covers 2000' - 3000' of the "killing zone".

Permanent guidewall and culvert system recently constructed at Paynes Prairie on US Highway 441 south of Gainesville, Florida. 

http://www.rattlesnakeroundup.com/index.html

Persecution

Rattlesnake RoundupsRattlesnake Roundups• Occur in several

southeastern states • Run by either non-profit

Jaycee’s clubs or for-profit companies

• 5 Crotalus spp. are targets; other harmless snakes taken incidentally

• Collecting methods often unethical

Rattlesnake RoundupsRattlesnake Roundups

Snakes often stockpiled by collectors for long periods of time

At roundup, measured, weighed, poked fun at, submitted to stresses and injuries

Often skinned alive, in public

Rattlesnake RoundupsRattlesnake Roundups

• Justified as a way to “educate the public”

• Also, to collect venom for research/antivenin industry

• Claims that there’s no effect, or a beneficial effect, on native populations

• However, effects of roundups on wild populations largely undocumented

Rattlesnake roundupsRattlesnake roundups

• The only organized events in the U.S. in which profits are made off the unregulated harvest of a vertebrate group

• WHY?

Declining Amphibians-HistoryDeclining Amphibians-History

• In 1989, at an international herp conference, workers expressed concern that their study organisms weren’t as common as they once were

Declining Amphibians-Declining Amphibians-

• Species extinctions and population declines around the world prior to 1990

• Subsequent studies have documented declines as they happen

• Few patterns emerged, other than that the most precipitous declines were among Anurans

Declining Amphibians-Declining Amphibians-

• Many of the same causes found for other biodiversity losses: – Habitat loss – Pollution, acid rain – Exotic species – Collecting

Amphibian Decline:What’s happening to all the frogs?

http://www.amphibiaweb.org/aw/declines/extinct.html#declines

Evidence of a complex problem

Two specimens of deformed frogs (Rana pipiens) from Vermont with missing parts of their hind limbs

Deformed Pacific Treefrog, Hyla regilla, from Oregon, with supernumerary hind limbs

What’s causing these Deformities/Declines?

predation and/or cannibalism, whereby some predator (even other tadpoles) may be nipping the limbs off of  tadpoles 

1) predation and/or cannibalism?

Retinoic Acid:Main effects of RA on amphibian limbs-

Methoprene?

Atrazine:

Diazinon:Suppresses cholinesterase (nervous system)

2) CHEMICAL POLLUTANTS?

Hayes found hermaphroditism in frogs at levels as low as 0.1 ppb. Even with today's limits, levels of 40 ppb atrazine have been measured in rain and spring water in parts of the Midwest, while atrazine in agricultural runoff can be present at several parts per million.

3) Parasites? http://www.jcu.edu.au/school/

phtm/PHTM/frogs/ampdis.htm

Ribeiroia ondatrae (trematodes)

Ribeiroia cercariae

Johnson et al. exposed tadpole Pacific tree frog (Hyla regilla) to the cercaria of a trematode parasite, Ribeiroia. They found that as the number of parasites per tadpoles rises, the percentage of abnormalities increases while survival decreases.

http://news-info.wustl.edu/tips/page/normal/961.html

Parasites cont.

Spirometra erinacei (tapeworm)

Pathogens?

Chytrid Fungus (Batrachochytrium dendrobatidis)

Mucor amphibiorum Infected frogs and toads have

fungi disseminated through their internal organs and skin

Infected frogs may:

• have discoloured skin • be sloughing, or peeling, on

the outside layers of its skin. This can vary from obvious peeling of skin (particularly on the feet), to a roughness of the frog's skin that you can barely see

• sit out in the open, not protecting itself by hiding

4) Climate Change?

Increase in temperature seems to be impacting amphibian populations

5) Habitat Loss

7) Exotic species

• Bullfrog

UV Radiation

• UVB Radiation?– Blaustein vs Adams

and Corn

Laws and Regulations: CITESLaws and Regulations: CITES

• Convention on International Trade in Endangered Species of Wild Fauna and Flora established by IUCN in 1973 – Regulates international trade in species of concern – Mandates that international trade in endangered

species is unlawful – Nearly 600 species of amphibian and reptile are

covered

Laws and Regulations: ESALaws and Regulations: ESA

• Signed into law by Nixon in 1973 – Far-reaching law; protects both domestic and foreign

animals and plants – Prohibits “take” of species of concern – Mandates that FWS and NMFS monitor populations

and develop a recovery strategy

Laws and Regulations: ESA Laws and Regulations: ESA listing processlisting process

• Anyone can petition to list a species – Must provide sound scientific basis for listing – FWS or NMFS reviews petition, may conduct

additional research, must make findings according to predetermined time schedule

– Decision to list or not published in Federal Register, including basis for decision

Laws and Regulations: ESA Laws and Regulations: ESA recovery processrecovery process

• FWS or NMFS drafts a Recovery Plan for the species in question – Delineates tasks and criteria needed for the recovery

of a species – Solicits public and expert comment on draft Recovery

Plan – Revises draft, issues final recovery plan

• Includes dollar estimates needed for recovery • Not a binding document

– Species is delisted or downlisted as criteria from Recovery Plan are met

– Critical habitat may be designated later

ESA: Herp Listing StatusESA: Herp Listing Status

99

15

49

0

25

50

75

100

Endangered

EmE

SAT

Threatened

ESA: Insular and Continental Amphibians and Reptiles

48

98

8

0

25

50

75

100

island

continental

marine

ESA Listed Amphibians by ESA Listed Amphibians by StateState

Was

hingto

n

Oregon

Alabam

a

Arizona

Nevad

a Wyo

min

gTexas

Califo

rnia

012345678

Alaba

ma

Arizon

a

Califo

rnia

Florid

a

Idah

o

Miss

ouri

Nevad

a

New M

exico

Ore

gon

Texas

Virgin

ia

Wes

t Virg

inia

ESA Listed Reptiles by StateESA Listed Reptiles by State

0

2

4

6

8

10

12

14

ESA: Herps with Recovery PlansESA: Herps with Recovery Plans

13

31 32

123

0

25

50

75

100

125

amphibians (42%) reptiles (26%)

recovery plans

listed species

ESA: Herps with Critical HabitatESA: Herps with Critical Habitat

19

134

0

20

40

60

80

100

120

140

14% w/Critical Habitat

Yes

No

ESA: U. S. Listings of Herps by ESA: U. S. Listings of Herps by YearYear

1

10

100

1000

10000

1980

1982

1984

1986

1988

1990

1992

1994

1996

1998

2000

# L

iste

d Amphibians

Reptiles

All species

ESA Listed Amphibians and ESA Listed Amphibians and Reptiles by GroupReptiles by Group

1714

41

24

2

37

19

0

5

10

15

20

25

30

35

40

45

Anura

Urodela

Chelonia

Crocodylia

Rhynchocephalia

Sauria

Serpentes

% of ESA Listed Species by % of ESA Listed Species by GroupGroup

100

0

10

20

30

40

50

60

70

80

90

100

Anura

Urodela

Chelonia

Crocodylia

Rhyncocephalia

Sauria

Serpentes

Human Population Density & Human Population Density & # ESA Listed Herps# ESA Listed Herps

Rept. = 0.3426x + 1.3969

R2 = 0.2383F 1,36 = 11.26, p = 0.002

Amph.= 0.0453x + 0.5344

R2 = 0.0108F 1,22 = 0.24, p = 0.63

0

0.5

1

1.5

2

2.5

3

-6 -4 -2 0 2 4

ln state population density

ln #

lis

ted

American alligator:American alligator:an ESA success storyan ESA success story

• American alligator was listed as threatened under precursuer to ESA in 1967.

• All subsequent “take” was illegal • Captive breeding and farming “ranches”

proliferated • Eggs collected in wild, incubated, then released

when hatched • Alligator recovered, delisted in 1987 • Now subject of 60 million $/ year industry

State laws and herpsState laws and herps

• Usually protected by state game and fish agency

• Funding through sales of fishing and hunting licenses (P-R act and D-J act, respectively)

• Often need fishing or hunting license to collect

• Often may not collect for sale • Bag limits, quotas imposed • States may have ESA-type

legislation

What can I do?

• Adopt a conservation ethic• Work directly in the area of conservation

– Help conduct research– Assist with conservation organizations– Become involved politically

• Educate yourself, family & friends about the importance of herps in the ecosystem

• Educate yourself, family & friends about the importance of having better “green” life choices– Try to have a lifestyle that incorporates sustainable methods– Support companies that work towards sustainability & are

supportive of the environment– Elect officials that support environmental policies

Conservation GroupsConservation Groups

• Conservation International

• The Wildlife Society

• Society for Conservation Biology

• The Wilderness Society

• Center for Biological Diversity

Conservation JournalsConservation Journals

• Conservation Biology • Biological Conservation • Southwest Naturalist • Journal of Wildlife

Management, Wildlife Society Bulletin

• Chelonian Conservation and Biology

When it comes to conservation and all the things of your life keep in mind these words

I am only one, but I am one.I cannot do everything, but I can do Something.I will not let what I cannot do interfere with what I can do.

Edward Everett Hale

Recommended