Amphibian Research and Monitoring Initiative: Rocky Mountain Region

Science Center Objects

Decline of amphibian populations worldwide has prompted an international effort to determine causes of decline in various locations and ecosytems. Some causes which have been suggested include habitat alteration, introduced species, disease, and environmental stressors such as ultraviolet radiation, agricultural chemicals in groundwater, and contaminants in atmospheric deposition. The Amphibian Research and Monitoring Initiative (ARMI) is an interdisciplinary nationwide effort to determine the status of amphibian populations and possible causes of their decline. In FY2000 the Biological Resources Division (BRD) of USGS began an inventory of amphibian populations, beginning with site that are part of the EPA/NPS PrimeNet monitoring network in National Parks and other sites on Department of Interior lands.


There is a need to link these amphibian population studies with hydrologic investigations that:

Image: USGS Scientist Conducting Amphibian Research

Dr. Erin Muths (ARMI scientist, USGS) sampling frogs at a field site on Mt. Evans, Colorado.

  1. characterize natural habitat suitability for amphibians, and
  2. determine the vulnerability of habitat to anthropogenic environmental stressors, and
  3. evaluate the role of natural variability and global change in climate.


  1. Characterize amphibian habitat using basin characteristics such as topographic setting, geology, soils, vegetation.
  2. Measure chemical composition of water at amphibian inventory sites to verify habitat characterization and identify potential environmental stressors.
  3. Determine basin characteristics and chemical constituents that are most important in determining population distribution of amphibians, and use these characteristics to classify habitats in the inventoried areas.
  4. Develop testable hypotheses to determine the role of habitat and environmental stressors in controlling the distribution of amphibian populations.
  5. Determine the interannual variability of climate, hydrology, and chemistry of habitats, and identify stressors that control catastrophic declines in amphibian populations at intensively-monitored sites.

See: Amphibian Research and Monitoring Initiative (ARMI)