Zoo scientists attempt to catch wild frogs to judge the health of the ecosystem

Amphibian Health and Stress Physiology

Zoo scientists hold a wild amphibian

Purpose

Lincoln Park Zoo scientists are monitoring amphibian disease and stress in order to determine how land use and restoration are impacting amphibian health throughout the Chicagoland area.

About

According to the International Union for Conservation of Nature (IUCN), amphibians are the most endangered taxonomic group in the world—at least one third of all known amphibian species are threatened with extinction. Threats include habitat loss and degradation, pollution, climate change, and disease, such as Batrachochytrium dendrobatidis (Bd), which is more widely known as the chytrid fungus.

Over recent years, Chicagoland has been subjected to a variety of stressors—including fragmentation, degradation, contamination, and habitat conversion— that have resulted in the loss of amphibian diversity.

Much like humans, animals are more susceptible to disease when experiencing high levels of stress. In order to assess the risk to local species, Lincoln Park Zoo scientists have spent years measuring the prevalence of Bd in Chicagoland, and area that has been subjected to a variety of stressors—including fragmentation, degradation, contamination, and habitat conversion— that have resulted in the loss of amphibian diversity.

Amphibian health is a good indicator of environmental health. Because of their porous skin, amphibians have a higher rate of exposure to toxins, and their health is a good indicator of environmental health. Changes to their environment, like urbanization and agricultural expansion, have the potential to affect amphibian health, so zoo scientists are using novel, non-invasive methods to monitor local frog populations as a representation of the ecosystem.

Amphibians secrete hormones and other bodily fluids through their skin—hence their “sliminess”—so zoo researchers developed several methods to measure amphibian stress hormones through these secretions.

Zoo scientists and their collaborators are collecting swab samples from local amphibians to measure stress hormones in conjunction with disease sampling. Their results will provide some insight on how land use and restoration are impacting amphibian health throughout the Chicagoland area.

Staff

Rachel Santymire, Ph.D.
Director
Davee Center for Epidemiology and Endocrinology
Mary Beth Manjerovic, Ph.D.
Adjunct Scientist
Davee Center for Epidemiology and Endocrinology; Urban Wildlife Institute

Contributors

Katie Fowler, M.S.