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USGS · 70003425

Trends in anuran occupancy from northeastern states of the North American Monitoring Program

Linda Weir·Ian J. Fiske·J. Andrew Royle
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Abstract

We present the first multi-year occupancy trends from North American Amphibian Monitoring Program (NAAMP) data in 10 northeastern states using seven years of data (2001-2007). NAAMP uses a calling survey technique where observers listen for anuran vocalizations along assigned random roadside routes. We were able to assess occupancy trends in 10 northeastern states for 16 species and one species complex, for 94 species/state combinations. We found no significant trends for 64 species/state combinations. For the remaining 30 species/state combinations with significant trends, these split between declining and increasing trends. On a species-by-species basis, two species had declining trends, with significant trends in six states for Pseudacris crucifer and four states for Bufo americanus . The trends of Rana catesbeiana significantly increased in four states, but had no trend in the remaining states.

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Linda Weir, Ian J. Fiske, J. Andrew Royle. 2009. Trends in anuran occupancy from northeastern states of the North American Monitoring Program. https://pubs.usgs.gov/publication/70003425

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