Date of Award


Document Type

Thesis: Open Access

Degree Name

MS Marine Science


Environmental and Ocean Sciences

Committee Chair

Richard E. Casey


Twenty-nine visits to Middle Rock, Islas Los Coranados, were made between March 1989 and September 1990, including 10 overnight visits. Breeding phenology was studied, including timing of colony attendance by adult birds, timing of egg laying, hatching, and fledging. Over 200 birds were banded to determine nest site tenacity and pair bond retention. Details were recorded on nest site selection, interspecific competition, breeding success, chick growth and plumage development, adult morphometrics, molt, food items, vocalizations, and ectoparasites.