Date of Award


Document Type


Degree Name

Master of Science


College of Arts and Sciences


Biology, MS

First Advisor

James L. Hayward

Second Advisor

Shandelle M. Henson

Third Advisor

Gordon J. Atkins


Using video recordings and scan counts, I examined the occurrence, sequences, and durations of behavior and environmental factors associated with courtship and copulation in glaucous-winged gulls, Larus glaucescens. Males and females in a pair had equivalent pre- and post-Mount behavior occurrences and durations. The main courtship sequence was Head Toss -- Courtship Beg/Respond -- Mounted/Mount, and felames appeared to initiate transitions between these pre-Mount behaviors. More Mounts occurred during the egg-laying stage of the breeding season, but copulation duration, wing-flag duration, and cloacal contacts per copulation showed no significant differences across sampling periods. Poisson analysis showed no significant grouping of Mounts in time during the days sampled. Bald eagle (Haliaeetus leucocephalus) disturbance was correlated with increased courtship and copulation frequency. Other environmental factors affecting courtship and copulation included day of year, tide height, and solar elevation. Peak Mounts and Courtship Begs per territory occurred two days before the Courtship Feeds and 10 days before peack clutch initiations.

Subject Area

Glaucous-winged gull, Courtship in animals

Creative Commons License

Creative Commons Attribution-No Derivative Works 4.0 International License
This work is licensed under a Creative Commons Attribution-No Derivative Works 4.0 International License.

Included in

Biology Commons