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Assessing Spatial Learning and Memory in Small Squamate Reptiles
Published on: January 3, 2017
When is a species declining? Optimizing survey effort to detect population changes in reptiles
David Sewell1, Gurutzeta Guillera-Arroita, Richard A Griffiths
1Durrell Institute of Conservation and Ecology, School of Anthropology and Conservation, University of Kent, Canterbury, Kent, United Kingdom.
Plos One
|September 1, 2012
Summary
Optimizing reptile surveys in the UK using occupancy modeling ensures reliable detection of widespread species. This approach helps set conservation targets by determining necessary survey effort for biodiversity assessments.
Area of Science:
- Ecology
- Conservation Biology
- Wildlife Management
Background:
- Biodiversity monitoring programs require reliable detection of population changes, which is challenging for cryptic species with imperfect detection.
- Optimizing survey design is crucial for effective wildlife management and conservation assessments.
Purpose of the Study:
- To optimize survey design for UK reptile monitoring programs using occupancy modeling and power analysis.
- To determine the survey effort required for reliable detection of widespread reptile species and to inform conservation outcome targets.
Main Methods:
- Occupancy modeling and power analysis were employed to assess survey design effectiveness.
- Reptile surveys were conducted six times annually from 2009-2010 at multiple sites, utilizing transect walks and artificial cover objects.
- Detection rates and probabilities were analyzed for six UK reptile species.
Main Results:
- Three to four survey visits using transect walks and artificial cover objects provided 95% certainty of detecting widespread reptile species.
- Artificial cover objects significantly improved detection rates and reduced misidentifications for most species.
- Detecting a 15% decline in widespread species with 85% power requires 886 sites surveyed thrice or 688 sites surveyed four times.
Conclusions:
- The study provides refined reptile survey protocols for the UK and globally.
- Occupancy modeling optimizes survey effort and aids in setting conservation targets for biodiversity assessments.
- Effective survey design is essential for reliable biodiversity monitoring and conservation success.
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