Northeast State of the Frogs: Development of Regional Analysis for Frog Call Survey Data from the North American Amphibian Monitoring Program

RCN Topic
Regional Indicators and Measures

This project will produce the first regional analysis of frog call survey data from the North American Amphibian Monitoring Program (NAAMP).  Eleven years (2001-2011) of survey data from the NAAMP will be used to provide a regional trend assessment and associated analytical methods for amphibians in the northeast.  NAAMP is a collaborative effort among USGS, State Agencies, and other partners, to monitor calling amphibians using a standard, peer-reviewed protocol.  NAAMP is active in over 20 states, including 11 northeastern states (Delaware, Maine, Maryland, Massachusetts, New Hampshire, New Jersey, Hudson region of New York, Pennsylvania, Vermont, Virginia, and West Virginia).  This project will develop the modeling and trend assessment framework for regional reporting, resulting in the first regional level analysis using NAAMP data.  In addition, this framework will become the methodology for future reporting on NAAMP results.

This RCN project addresses the RCN Topic 6: Design and implement monitoring protocols, measures, and indicators for NE Species of Greatest Conservation Need (SGCN) and targets one of the preferred taxonomic groups, amphibians.  There are 30 species of frogs and toads in the Northeast.  We anticipate being able to report occupancy trends for 18, with the majority of omitted species being restricted to southeastern Virginia.  Of the 18 species, 12 are SGCN in one or more northeastern states.  In addition, Northeast Partners in Amphibian and Reptile Conservation (NEPARC) has proposed 7 of these species as "high responsibilty" for the Northeast.

We present the first regional trends in anuran occupancy from North American Amphibian Monitoring Program (NAAMP) data from 11 northeastern states using 11 years of data. NAAMP is a long-term monitoring program where observers collect data at assigned random roadside routes using a calling survey technique. We assessed occupancy trends for 17 species. Eight species had regional trends whose 95% posterior interval did not include zero; of these seven were negative (Anaxyrus fowleri, Acris crepitans, Pseudacris brachyphona, Pseudacris feriarum-kalmi complex, Lithobates palustris, Lithobates pipiens, and Lithobates sphenocephalus) and one was positive (Hyla versicolor-chrysoscelis complex). We also assessed state level trends for 103 species/state combinations; of these, 29 showed a decline and nine showed an increase in occupancy.

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