[common frogs mating]...Cold and Clammy, But You Gotta Love Us !

Animals as Environmental Sentinels of Human Pollution Feature Creatures = Amphibians Feature Creatures = Amphibians By Leslie A. Dierauf, VMD By Leslie A. Dierauf, VMD Santa Fe, New Mexico Santa Fe, New Mexico

Sentinels (O’Brien, 1993) Sentinels (O’Brien, 1993) “...organisms whose known characteristics can be measured to assess the extent of environmental…implications…and to provide early warning of those implications.”

Pollution Contamination of the earth’s environment with materials that interfere with health, quality of life, or the natural functioning of ecosystems.

At Air/Water Interface [southern leopard frog]

On Land, Living In Outdoor Environs

Three Ways In Which Amphibians Are Affected By Their Environment Bullfrog skin Eggs w/tadpoles Tadpole w/gills

Human Population Growth: Its Effects on Sentinels b Loss or modification of habitat b Predation b Introduction of non-native species b Air and water quality impacts b Climate changes

Air Quality Effects b Greenhouse gas production b Volatile organic compounds b Aerosolized pesticides & other chemicals b Particulate matter and silt/sedimentation

Water Quality & Quantity Effects b Herbicides b Pesticides b Heavy metals b Other materials in run-off b Decreased pH & Increased salinity b Lowering of water tables b Loss of freshwater spring flows

Trematode Life-Cycle Deformed Frog Larval Form of Trematode Encysts in Leg Bud of Tadpole Snail Ingests Trematode Bird Eats Tadpole Digestive Juices Release Encysted Larvae

Golden Toads - Monteverde Cloudforest North Central Costa Rica

Climate Change Effects b Increased ultraviolet light b Acid rain b Global warming b Disease

UVB Radiation Effects on Developing Eggs

Maintaining Biological Diversity Strawberry Poison Dart Frogs Mating

Bridging the Gap - Who? Public Health Veterinarians Epidemiologists Applied and Basic Research Scientists Small Animal Veterinarians (pocket pets) Exotic Animal Clinicians Wildlife Veterinarians Zoo Veterinarians Ecosystem Health Veterinarians

Bridging the Gap - How? Amphibian Physiology Reproductive Physiology Parasitology Disease Diagnosis Physical Environs Alterations Reproducible Results

Organism & Organism & Its Response Its Environment To the Environment Disease Diagnosis Ecosyst’m Pathology Health Epidemiol’y Morbidity & Mortality Envir’l Treatment Health & Care Life Hx Environ’l Factors Keen Observat’n Population Dynamics Habitat Health Field Studies

Bridging the Gap - Why? Healthy Environs Mean Healthy Animals and Humans Veterinarians have unique skills to communicate science simply Multi- and Inter-disciplinary research efforts recognize the value of animals as sentinels value of animals as sentinels Veterinarians are trained in systematic observation & reasoning Attention to individual cases may help explain whether, how, and why a population is changing whether, how, and why a population is changing Use of clinical evidence and clinical judgement Long-term monitoring and consistency

Some Suggested Causes of Amphibian Declines & Deformities Habitat Modification and/or Destruction Predation--Introduced Non-Native Competitors Volatile Organic Compounds/Skin, Eggs, Tads Air- & Water-Borne Chemicals, Heavy Metals... Acid Rain and Increased UVB Exposure Retinoids, such as Retinoic Acid Climate Change and Emerging Diseases Trematodes, Ribeiroia spp.Encysting at Legbuds Fungi, such as Chytrid Bactrochochytrium spp. Iridescent Viruses, such as Iridovirus (ATV)

Amphibian Up-to-Date Websites (American Veterinary Medical Assoc) (Savannah River Ecology Lab) (USGS, Biological Research Service) (Frogwatch--Local Reports of Nation) cmgm.stanford.edu/~meisen/herp/ (Stanford University Research) (U.S. Fish and Wildlife Service)