Increasing the Accuracy of Productivity and Survival Estimates in Assessing Landbird Population Status
The conservation of species with declining populations requires information on population demography and identification of factors that limit population growth. For landbird species, an understanding of large-scale population declines often requires assessment of local population processes, including the production of offspring, the survival of those offspring, and adult survival. Population growth has been modeled for several species of landbirds to date, and these studies have provided important information on relationships between population status and population-limiting factors. Several recent studies have illuminated field methods and analytical techniques that can aid in increasing the accuracy of productivity and survival estimates for population models. We reviewed these methods and recommend their implementation, including quantification of the season-long productivity of individuals, collection of empirical data on juvenile survival during the postfledging and overwintering periods, and incorporation of adult breeding dispersal into annual adult survival estimates. Such methods will allow for more accurate assessment of population status and provide a better understanding of the factors on which to focus our conservation efforts.
Keywords: Mayfield estimate; adult survival; ave terrestre; demografía; demography; estimación de Mayfield; juvenile survival; landbird; modelos poblacionales; nest success; population models; productividad; productivity; supervivencia de adultos; supervivencia de juveniles; éxito de anidación
Document Type: Research Article
Affiliations: 1: Department of Biology, Program in Ecology, 321 Mueller Lab, Pennsylvania State University, University Park, PA 16802, U.S.A., Email: [email protected] 2: National Park Service, 204C Ferguson Building, Pennsylvania State University, University Park, PA 16802, U.S.A.
Publication date: February 1, 2005