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Estimating site occupancy, colonization, and local extinction when a species is detected imperfectly

Ecology

6085 MacKenzie.pdf
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Abstract

Few species are likely to be so evident that they will always be detected when present. Failing to allow for the possibility that a target species was present, but undetected, at a site will lead to biased estimates of site occupancy, colonization, and local extinction probabilities. These population vital rates are often of interest in long-term monitoring programs and metapopulation studies. We present a model that enables direct estimation of these parameters when the probability of detecting the species is less than 1. The model does not require any assumptions of process stationarity, as do some previous methods, but does require detection/nondetection data to be collected in a manner similar to Pollock's robust design as used in mark?recapture studies. Via simulation, we show that the model provides good estimates of parameters for most scenarios considered. We illustrate the method with data from monitoring programs of Northern Spotted Owls (Strix occidentalis caurina) in northern California and tiger salamanders (Ambystoma tigrinum) in Minnesota, USA.

Additional Publication Details

Publication type:
Article
Publication Subtype:
Journal Article
Title:
Estimating site occupancy, colonization, and local extinction when a species is detected imperfectly
Series title:
Ecology
Volume
84
Issue:
8
Year Published:
2003
Language:
English
Contributing office(s):
Patuxent Wildlife Research Center
Description:
2200-2207
Larger Work Type:
Article
Larger Work Subtype:
Journal Article
First page:
2200
Last page:
2207
Number of Pages:
8