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Publication Date

Summer 2014

Degree Type

Thesis - Campus Access Only

Degree Name

Master of Science (MS)

Department

Biological Sciences

Advisor

Scott A. Shaffer

Keywords

albatross, biologging, egg turning, gull, incubation, seabirds

Subject Areas

Ecology

Abstract

Egg turning behavior across the course of incubation is vital for proper avian embryonic development and hatching success, but temporal associations between egg attendance patterns and turning behaviors have not been studied in wild birds. Here, I use miniature, self-contained data loggers to characterize egg turning rates and angle changes of eggs in two wild, long-lived seabird species: western gulls (Larus occidentalis) and Laysan albatrosses (Phoebastria immutabilis). Egg turning behaviors were examined temporally across early, middle, and late incubation periods and also grouped by 24-h periods and diurnal cycles. Results indicate 1) egg turning rates and angle changes vary according to diurnal cycles and incubation day length in each species; 2) egg turning behaviors remain similar throughout incubation, resulting in a consistent environment for developing chicks; 3) using differing temporal scales to examine egg turning reveals changes in such behaviors, and 4) egg turning rates appear to be highly conserved between species despite large differences in egg size and lack of close phylogenies, whereas angle changes exhibit greater variation between species. Overall, differences in incubation behaviors between species may be subtle but impactful and, as such, call for consistent methodologies and the ability to examine incubation patterns over small, species-relevant time scales.

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