Integrating methods to determine breeding and nesting status of 3 western songbirds

Determining reproductive success in birds is important to understand population dynamics, habitat quality, and features necessary for breeding. We incorporated behavioral observations, nest monitoring, and a reproductive index (Vickery et al. 1992a) to: 1) categorize breeding status (breeders and nonbreeders) of painted redstarts (Myioborus pictus), plumbeous vireos (Vireo plumbeus), and western wood-pewees (Contopus sordidulus); 2) locate their nests; 3) monitor nest status; and 4) determine nest success and parasitism rates in 14 canyons of the Huachuca and Santa Rita mountains, Arizona during 1994-1995. We located 256 nests along 41.4 km of creek and correctly predicted the reproductive state of breeding birds on 61-79% of the visits without having to check nests. Nest success ranged from 35 to 52%, and parasitism rates were 25% for painted redstart and 40% for plumbeous vireo. Integration of multiple methods allowed us to concentrate on breeding status of specific species over large areas while reducing nest visits and still obtaining information on nest location, breeding status, and nesting success. The predictive ability of the reproductive index in a forested system will increase knowledge of breeding status of birds such as cavity nesters, whose nests cannot be checked readily, rare species, and other bird species that are sensitive to disturbance.

Integrating methods to determine breeding and nesting status of 3 western songbirds Academic Article