Evaluating Calling Surveys

Sam Droege and Paige Eagle

in Amphibian Declines

Published by University of California Press

Published in print June 2005 | ISBN: 9780520235922
Published online March 2012 | e-ISBN: 9780520929432 | DOI:
Evaluating Calling Surveys

Show Summary Details


In North America, approximately fifty-five of the 103 species of anurans can be surveyed readily by using counts of vocalizing males as an index to their presence or population size. Such surveys are most applicable to eastern and northern parts of the continent, where almost all species regularly vocalize and breeding seasons extend over several weeks. Calling surveys of amphibians are designed to provide an index to changes in amphibian populations. The technique can be applied in monitoring sampling designs to provide estimates of abundance and change at scales ranging from continental down to single wetlands. By correlating observed trends and distribution patterns with ancillary variables, it is also possible to gain insight into the factors affecting population changes over time. For example, population declines may be associated with agricultural regions, while population increases may occur in regions where wetlands have increased.

Keywords: North America; amphibians; calling surveys; anurans; breeding; monitoring; sampling; population declines

Chapter.  4304 words. 

Subjects: Zoology and Animal Sciences

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.