Graduation Date

Fall 2016

Document Type



Master of Science degree with a major in Natural Resources, option Wildlife

Committee Chair Name

Dr. Mark A. Colwell

Committee Chair Affiliation

HSU Faculty or Staff

Second Committee Member Name

Dr. Daniel C. Barton

Second Committee Member Affiliation

HSU Faculty or Staff

Third Committee Member Name

Dr. Jared D. Wolfe

Third Committee Member Affiliation

HSU Faculty or Staff


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 began molting an average of 71 days earlier than females, and birds that breed in northern California began molting an average of 43 days earlier than those that breed in Oregon and Washington. Earlier initiation was correlated to longer molt duration, which suggests that males need more time than females to complete alternate plumage.

Citation Style

Journal of Wildlife Management