Amphibian malformations and decline. Some Malformations. Polymelia. Amelia. Anophthalmia. Ectromelia. Why are amphibians so susceptible to mutations?. What is causing the malformations?. North American Reporting Center for Amphibian Malformations Ohio. Amphibian declines. - PowerPoint PPT Presentation
Amphibian malformations and decline1Polymelia
EctromeliaAnophthalmia3Why are amphibians so susceptible to mutations?
4Aquatic/terrestrial life history Relatively unprotected eggs External fertilization Skin permeability Biomagnifications of contaminants
What is causing the malformations?
5UV-B radiationincreased UVB radiation due to ozone depletion may cause bilateral limb truncationEnvironmental ToxinsGeneral pollutants (gas, radiator fluid, salt)Herbicide/pesticide exposureEndocrine disruptorsand hormone mimicsDioxides and furansDifficult to clean upBiomagnification
North American Reporting Centerfor Amphibian MalformationsOhio
Bufo periglenesAtelopus ebenoides marinkelleiAtelopus nahumae
Declining Amphibian Populations
8Habitat loss and fragmentationPrimarily wetland lossClimatic changesInfectious diseaseFungal infectionViral infection - IridovirusInvasive species predationSkin permeabilityOvercollection
Hotspots of Amphibian DeclineSource: http://elib.cs.berkeley.edu/aw/index.htmlIn the U.S., declines are particularly serious in California, the Rocky Mountains, the Southwest, and Puerto Rico. Worldwide, decline "hot spots" also include Australia and Central America.9
Bufo baxteriWhy care about amphibian declines/malformations?
11Ecosystem Structure and FunctionAquaticGrazersNutrient dynamicsBioturbationFacilitation of grazers/collectorsEggs + tadpoles supplement energy
Ecosystem structure and function
12TerrestrialInsect control!Important prey1 species akin to 2
Why else do we care?
13Environmental quality indicators - biomarkersFoodResearchPlus, theyre cool