Text of AMPHIBIAN AND REPTILE CONSERVATION Yosemite Monteverde
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AMPHIBIAN AND REPTILE CONSERVATION
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Yosemite Monteverde
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Global Amphibian Assessment The first-ever comprehensive
assessment of the conservation status of the world's 5,918 known
species of frogs, toads, salamanders, and caecilians Extinct (or
extinct in the wild) Critically Endangered Endangered Vulnerable
Not Threatened Least Concern Data Deficient
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Exam III Last day of classThurs, Dec. 9 Read Ch 8, 9, 10, and
11 from Gibbs et al. (short chapters) Read Ch. 14 from Vitt and
Caldwell Be familiar with invited lecture (Thomas) and Demography
and Conservation overview lecture by Gibbs Know your NYS herp
regs
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Global Amphibian Assessment Key Findings Nearly one-third (32%)
of the worlds amphibian species are threatened, representing 1,856
species (vs. 12% of birds and 23% of mammals) As many as 168
amphibian species may already be extinct 43% of species are
declining in population, vs. < 1 % increasing Highest numbers of
threatened species are in Latin American countries such as Colombia
(208), Mexico (191), and Ecuador (163)
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Reptiles in Decline The Global Decline of Reptiles, Dj Vu
Amphibians BioScience 2000* by J. Whitfield Gibbons, David E.
Scott, Travis J. Ryan, Kurt A. Buhlmann, Tracey D. Tuberville,
Brian S. Metts, Judith L. Greene, Tony Mills, Yale Leiden, Sean
Poppy, and Chris Winne *http://www.uga.edu/srelherp/staff/Winne%
20-%20gibbons%20et%20al%202000.pdf
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Most anurans and many salamanders breed in wetlands. Many
reptiles also highly dependent Loss of wetlands = loss of
amphibians and reptiles Lower 48 states lost an average of 54% of
the estimated original 221 million acres of wetlands from 1780s to
the 1980s Iowa, for example, lost approximately 95% of its
wetlands. HABITAT LOSS IS THE GREATEST THREAT
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Extinct! Vegas Valley Leopard frog (Rana fisheri)
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Declines in habitat quality
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Losses of Temporary Wetlands Especially important Many
eliminated by: Grading, Mosquito control, Human tidiness Extremely
vulnerable Largely unprotected
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Created by John Rozum, NEMO National CoordinatorJohn RozumNEMO
National Coordinator
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Source: Megan Griffiths
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Introduced Species Predation of alien species on native species
Competition for resources Introduction of pathogens by non-native
species Hybridization
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Decline of the Mountain Yellow-legged Frog Rana mucosa
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Impact of stocked fish on yellow-legged frog Knapp et al. 2001
Ecological Monographs
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Reptiles and amphibians can be invaders, too
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Over-harvesting of reptiles Sea turtles for food Freshwater
turtles for food Iguanids for food Anything intriguing for the pet
trade
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Last Saturday in January at the new RattleSnake Grounds US 84
Whigham, Georgia 9:00 am to 5:00pm Arts and Crafts - Food Booths
RATTLESNAKE EXIHIBITS Don't forget to try some deep-fried Western
Diamondback Rattlesnake meat and The Gun, Knife and Coin show that
will be offered as well Over 123 tons of Western Diamondback
Rattlesnakes turned in to date Rattlesnake Round-up
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Gopher tortoises in Florida
http://www.empireoftheturtle.com/Florida/gopherus_polyphemus.htm
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Asian turtle crisis
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Over-collecting and amphibians People collect amphibians for
food medicines bait, pets even for teaching biology. In some parts
of the world collecting alone appears to cause declines. India, for
example, has banned frog exports because of pest increases in rice
paddies
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Real 3" to 4" frogs preserved in anise scented liquid. Three
frogs per jar A sure thing for all game fish.
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Eating Frogs to Extinction, IAN G.WARKENTIN et al.,
Conservation Biology
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Dried newts in Lhasa market
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NYS law protecting reptiles and amphibiansknow these!
Regulation: Chapter 1 Fish and Wildlife
http://www.dec.ny.gov/regs/2494.html Part 3: Reptiles and
Amphibians * Section 3.1: Diamondback Terrapins * Section 3.2:
Native Turtles * Section 3.3: Native Snakes * Section 3.4: Native
Lizards * Section 3.5: Native Frogs * Section 3.6: Native
Salamanders
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Parasites and disease: Emerging pathogens: Chytridiomycosis
Frogs may be suffocating because of the fungal growth In reaction
to chytrid infections, they lay down extra layers of keratin in
their skin. Another possibility is that the fungus is releasing a
toxin. Latest news: ionic balance
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Carcass of an Australian amphibian (Myxophyes fasciolatus) that
died from cutaneous chytridiomycosis. This individual died in a
mass mortality event in a captive collection.
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Chytrid Fungi Chytrid fungi is at least a proximate cause of
current die-offs in Central and North America New chytrids moving
in waves around world Direct cause? Stress-induced? New
pathogen?
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Spread by Xenopus? In the 1930s, discovered that a female
Xenopus would ovulate if injected with the urine from a pregnant
woman Hormone chorionic gonadotropin was the active ingredient. In
the 1940s and 50s, the only available pregnancy test Many hospitals
kept Xenopus but many releases: California, Chile, England etc.
Future? Probiotics? Adaptation?
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Contaminants Consider Atrazine, a common weed killer More than
60 million pounds applied last year in the United States alone.
Used to control weeds on about two-thirds of all U.S. corn and
sorghum acreage - improves corn yield by slightly more than 4%
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Collects in frog breeding ponds Atrazine ups production of the
enzyme aromatase, which converts androgen hormones to estrogen
hormones Contaminants - Atrazine
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Abnormal gonads in a male Xenopus frog, the result of exposure
to the herbicide atrazine. The frog has become a hermaphrodite,
that is, it has both male (testes) and female (ovaries) sex organs
Tyrone Hayes with Colorado river toad (Bufo alvarius). Peg
Skorpinski photo. April 16 issue of Proceedings of the National
Academy of Sciences
Parasites and deformities 5% natural background rate At least
41 species representing 35 genera and 21 families of trematodes
have amphibian larvae as intermediate hosts Also use snails as
hosts Trematode larvae burrow into amphibian tissues to form cysts
and affect limb development
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Trematodes? Natural or unnatural? Trematode densities are
heavily influenced by water quality Snail hosts benefit from
wetland eutrophication Increased N concentrations can boost
populations
