Survey methods for the purple martin in California

Abstract

The purple martin (Progne subis) has declined substantially in numbers and geographic range since the 1980s. Surveys and monitoring are needed to better understand the status of the species, in order to set conservation priorities and direct actions. Purple martins in California often breed in habitats that differ from those in other areas of the species’ range. The species’ sparse distribution, colonial nature, and frequent use of inaccessible nests sites require specialized methodologies to determine suitable nesting habitat, occupancy, numbers, and reproductive success. I present a range of methods available to monitor nesting purple martins in the variety of nesting substrates in which they nest in California. These methods should improve efficiency and accuracy of surveys and provide comparable results that can be used to evaluate regional or statewide trends.

Keywords

• occupancy
• population size
• productivity
• progne subis
• purple martin
• survey methods