Estimating Probabilities of Survival of Male Bachman's Sparrows From Plot-Based, Mark–Resighting, Off-Plot Surveys and Multi-Strata Models

Abstract

Abstract. Bachman's Sparrow (Peucaea aestivalis) is listed as a species of conservation concern throughout its range and therefore an important candidate for demographic studies. We estimated probabilities of males' annual survival by monitoring a large color-marked population for 4 years by using a combination of (1) mark-resighting within a primary study area and (2) surveys outside the primary area to document emigration. We used multi-strata models to assess probabilities of survival, detection, and movement between the primary study area and the surrounding landscape. In the top models included in our confidence set, probabilities of annual survival were ≥0.68. Probabilities of detection and dispersal varied among the top models but averaged ≥0.86 and ≤0.14, respectively, for individuals in the primary study area. We used a survival probability of 0.68 in combination with published information on the species' productivity to construct a two-stage Leslie matrix. Survival of adult males had the greates...