Reproductive success of Florida Scrub Jay (Aphelocoma coerulescens) pairs without helpers correlates with habitat variables and female breeding experience

Abstract

Extensive research has focused on effects of non-breeding helpers on the reproductive success of cooperatively breeding birds, yet in the cooperatively breeding Florida Scrub Jay Aphelocoma coerulescens about half of breeding pairs do not have helpers in any given year. We tested for effects of breeder experience and environmental variables (acorn abundance, fire history and territory size) on reproductive output of breeding pairs that lacked helpers. In generalized linear mixed models, explanatory variables that best explained variation in reproductive output included female breeder experience, time since fire, territory size and acorn crop. Our results emphasize that active habitat management through prescribed fire enhances the reproductive success of this declining bird across a diversity of social group compositions.