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Balancing predation and egg harvest in a colonial seabird: A simulation model

January 1, 2006

We developed an individual-based model to study the effects of different regimes of harvesting eggs and natural predation on reproductive success in a colony of the glaucous-winged gull (Larus glaucescens) in Glacier Bay National Park, Alaska. The model incorporates the sequence of egg laying, relaying, and incubation to hatching for individual nests and calculates hatching success, incubation length, and the total number of eggs laid (as a result of re-nesting and relaying) in all nests in the colony. Stochasticity is incorporated in the distribution of nest lay dates, predation rates, and nests attacked during predation and harvest events. We estimated parameter values by fitting the model to data collected at a small colony during 1999 and 2000 using maximum likelihood. We then simulated harvests and analyzed model predictions. Model outputs indicate that harvesting early, and at one time, provides a predictable take of eggs with the least impact to gulls.

Publication Year 2006
Title Balancing predation and egg harvest in a colonial seabird: A simulation model
DOI 10.1016/j.ecolmodel.2005.11.002
Authors Stephani Zador, John F. Piatt, A. E. Punt
Publication Type Article
Publication Subtype Journal Article
Series Title Ecological Modelling
Index ID 70028407
Record Source USGS Publications Warehouse
USGS Organization Alaska Science Center