Management Strategies for Reversing Declines in Landbirds of Conservation Concern on Military Installations: Enhanced Species-Landscape Models of Avian Demographics

摘要

Here we report on the progress of model enhancements considering spatio-temporal environmental variation. The Legacy-funded MAPS dataset covers a large area of the United States and the different locations experience very different weather patterns during the breeding season. In addition, many species are migrants and a population from one location may experience very different winter conditions to those experienced by a population from another location that overwinters in a different portion of the winter range. Using 1994-2002 data we noticed that reproductive success was high towards the end of the period such that 24 of 34 species analyzed experienced overall increases in young and reproductive success between 1994 and 2002. Trends in numbers of young significantly increased for nine species including three species of conservation concern, Acadian Flycatcher, Prairie Warbler, and Painted Bunting. In all cases, the two most productive years of the whole period occurred in those last four years (1999-2002). Analysis of 1994-2005 data showed, for some species (e.g. Painted Bunting), further drastic increases in numbers of adults and young captured. Previous research (Nott 2002, Nott et al. 2002, Sillett et al. 2002) showed that high annual variation correlated with weather conditions on the both the breeding and overwintering grounds.