Increased summer food supply decreases non-breeding movement in black-legged kittiwakes.

Increased summer food supply decreases non-breeding movement in black-legged kittiwakes. Biol Lett. 2020 Jan;16(1):20190725 Authors: Whelan S, Hatch SA, Irons DB, McKnight A, Elliott KH Abstract Individual condition at one stage of the annual cycle is expected to influence behaviour during subsequent stages, yet experimental evidence of food-mediated carry-over effects is scarce. We used a food supplementation experiment to test the effects of food supply during the breeding season on migration phenology and non-breeding behaviour. We provided an unlimited supply of fish to black-legged kittiwakes (Rissa tridactyla) during their breeding season on Middleton Island, Alaska, monitored reproductive phenology and breeding success, and used light-level geolocation to observe non-breeding behaviour. Among successful breeders, fed kittiwakes departed the colony earlier than unfed controls. Fed kittiwakes travelled less than controls during the breeding season, contracting their non-breeding range. Our results demonstrate that food supply during the breeding season affects non-breeding phenology, movement and distribution, providing a potential behavioural mechanism underlying observed survival costs of reproduction. PMID: 31937217 [PubMed - in process]
Source: Biology Letters - Category: Biology Authors: Tags: Biol Lett Source Type: research