RARMI: Northern Rocky Mountain Science Center (NOROCK) Apex Sites

Science Center Objects

In contrast to RARMI study areas in Colorado that have 10 or more years of records of continuous population monitoring, there are fewer long-term datasets for amphibian populations in the northern Rocky Mountains. The exception is an ongoing study of Columbia spotted frogs at Lodge Creek, Yellowstone National Park. Three other long-term research and monitoring areas have been established in the northern Rocky Mountains since 1999.

Boreal toad on a burned log.
Boreal toad on a burned log.Public domain

Glacier National Park

Three watersheds in Glacier National Park are monitored annually to track changes in the number of breeding sites of boreal toads (Bufo boreas). These watersheds were selected because they are the only areas in the park where we have discovered large numbers (>20) of boreal toad breeding sites. Long-toed salamanders (Ambystoma macrodactylum) and Columbia spotted frogs (Rana luteiventris), which are common in Glacier National Park, also breed in each of these monitoring areas. Annual monitoring networks of breeding sites will help us establish turnover rates of local populations, information necessary to determine whether amphibians are declining in the region. Declines should be manifested by a loss of populations that exceeds colonization rates.

Bitterroot Mountains, MT

In 1999, we began monitoring breeding of Columbia spotted frogs, long-toed salamanders, and Pacific treefrogs (Pseudacris regilla) at Lost Horse Creek Marsh in the Bitterroot Mountains of western Montana. We have counted egg masses of Columbia spotted frogs since 1999, and in 2000 began a capture-recapture study of Columbia spotted frogs. Our objectives are to measure annual variation in population size, survival and recruitment, and investigate breeding phenology and development. Egg masses of Columbia spotted frogs are also counted at other sites in the area to monitor the size of the female populations.

Lodge Creek, Yellowstone National Park, WY

Researchers at Idaho State University have studied and monitored amphibian populations in the Lodge Creek area since 1991. Through a cooperative agreement with USGS, this area became an apex site in 2000. Monitoring at this site allows us to continue research on Columbia spotted frogs that was started in 1953 by herpetologist Dr. Frederick B. Turner. Detailed, long-term information about population characteristics and seasonal habitat use of amphibian populations is rare but very important for amphibian conservation efforts. We monitor breeding sites and conduct distribution surveys through the summer and fall to assess possible changes in habitat use within the study area. To determine adult population size, we use digital photography to identify individuals and apply mark-recapture population size estimation techniques. Earlier results from this study revealed that piecemeal development of the area around Lodge Creek since the 1950s resulted in an almost 80% decline in Columbia spotted frogs between 1955 and 1995. 

We work with park resource managers to implement measures that may help protect this population, such as fencing key areas to exclude horses and retaining woody debris in frog movement corridors. We also use the Lodge Creek study area for educational efforts such as field courses through the Yellowstone Association Institute. The Lodge Creek study area is featured in a public television documentary on biodiversity and habitat fragmentation produced by the Natural Heritage Project of the Idaho Museum of Natural History.

National Elk Refuge, Jackson Hole, WY

The first known occurrence of infection of amphibians by chytrid fungus in the northern Rocky Mountains was found in boreal toads on the National Elk Refuge in the summer of 2000. We continue to monitor the area to determine how the disease outbreak is affecting the toad and Columbia spotted frog populations. We plan to continue monitoring reproductive sites to estimate the numbers of egg masses and population size of breeding females, and to search for signs of disease outbreaks

Lost Trail National Wildlife Refuge, Montana, MT

Surveys of potential breeding sites during 2001 and 2002 revealed a large breeding population of boreal toads (Bufo boreas) at Lost Trail National Wildlife Refuge. We suspect this is one of the largest populations known in the Rocky Mountains. B. boreas has experienced severe declines in the southern Rocky Mountains, and is a US Forest Service species of concern in Region 1. Recent surveys of >2000 potential breeding sites throughout the northern Rocky Mountains have found this species at <5% of sites, and surveys in the 1990s revealed that B. boreas was absent from many historic localities. There are few data for comparison, but B. boreas seems less common than indicated in historical accounts and may be experiencing a decline.

We established a long-term capture-recapture program of adult B. boreas at Lost Trail NWR in 2003 in collaboration with US Fish and Wildlife Service biologists to determine population size and trends. The capture-recapture study will complement our annual surveys of breeding sites that are used to determine population status (breeding population present/not detected). Each toad is measured (snout-vent length) and receives a passive integrated transponder (PIT tag) injected dorsally for unique identification. Passive integrated transponder tags are commonly used in amphibians, including in previous studies of B. boreas. There is potential for tag loss and this is being evaluated by batch marking all tagged animals. Skeletochronology of phalanges (toes) is used to determine age of some breeding individuals.