Population Biology Commons^™

Evaluating Brandt’S Cormorant (Phalacrocorax Penicillatus) Reproductive Success: Effects Of Parental Care Behaviors And Estimating Individual Chick Survival, Shannon Murphy

Cal Poly Humboldt theses and projects

Variation in reproductive success is widely measured in seabird biology in an effort to indicate changes in the marine environment, or understand basic questions about ecology or conservation of seabirds. When variation in seabird reproductive success is suggested to indicate changes in the marine environment without identifying the proximate causes of such variation, inference is limited to association, and the proximate causes themselves could prove more effective as indicators. My study informs this problem by examining and quantifying proximate causes of variation in reproductive success, at the level of nests and individual chicks.

I used video of Brandt’s Cormorant ( …

Molt In Individuals: A Description Of Prealternate Molt Phenology In A Population Of Snowy Plovers In Humboldt County, California, Alexa Dejoannis

Cal Poly Humboldt theses and projects

Molt in birds is an essential physiological process. Intrinsic and extrinsic conditions, such as age, sex, location, or food stress, may cause individual variation in molt phenology. This study describes the timing of prealternate molt in western snowy plovers (Charadrius nivosus nivosus) wintering in Humboldt County, California, USA. Between July 2014 and April 2015, I photographed uniquely marked plovers twice a month and assigned dates of initiation and completion. I modeled sex, age, hatch date, and breeding location as predictors of molt phenology. I observed prealternate molt from October to April, which is earlier than previously described. Males …