Predation risk affects egg mass but not egg steroid hormone concentrations in yellow-legged gulls.

ABSTRACT: Predators have both direct, consumptive effects on their prey and non-lethal effects on physiology and behavior, including reproductive decisions, with cascading effects on prey ecology and evolution. Here, we experimentally tested such non-lethal effects of exposure to increased predation risk on clutch size, egg mass, and the concentration of yolk steroid hormones in the yellow-legged gull Larus michahellis. We simulated increased predation risk by displaying stuffed predators (adult fox Vulpes vulpes, and adult buzzard Buteo buteo) to breeding adults before egg laying. The concentration of corticosterone, which has been shown to increase under exposure to maternal predation risk in other species, and of testosterone did not differ between eggs from mothers exposed t

SUBMITTER: Possenti CD 

PROVIDER: S-EPMC6688572 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature