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Full-Text Articles in Animal Sciences
Foraging-Related Activity Of Bald Eagles At A Washington Seabird Colony And Seal Rookery, James L. Hayward, Joseph G. Galusha, Shandelle M. Henson
Foraging-Related Activity Of Bald Eagles At A Washington Seabird Colony And Seal Rookery, James L. Hayward, Joseph G. Galusha, Shandelle M. Henson
Faculty Publications
From 1980 to 1998, Washington's Bald Eagle (Haliaeetus leucocephalus) population increased at an annual rate of 10. Over the same time period, foraging activity of Bald Eagles at marine bird breeding colonies also increased. From 1993 to 2008, we observed foraging-related behavior of Bald Eagles on Violet Point, Protection Island. This island hosts more than 70 of the breeding seabirds in Washington's inner seaways and serves as an important rookery for harbor seals (Phoca vitulina). We found that (1) eagles landed more frequently in seal haul-out (beach) areas than in gull-nesting (non-beach) areas of Violet Point, and that subadult eagles …
Socially Induced Synchronization Of Every-Other-Day Egg Laying In A Seabird Colony, Shandelle M. Henson, James L. Hayward, J. M. Cushing, Joseph C. Galusha
Socially Induced Synchronization Of Every-Other-Day Egg Laying In A Seabird Colony, Shandelle M. Henson, James L. Hayward, J. M. Cushing, Joseph C. Galusha
Faculty Publications
Spontaneous oscillator synchrony has been documented in a wide variety of electrical, mechanical, chemical, and biological systems, including the menstrual cycles of women and estrous cycles of Norway Rats (Rattus norvegicus). In temperate regions, many colonial birds breed seasonally in a time window set by photoperiod; some studies have suggested that heightened social stimulation in denser colonies can lead to a tightened annual reproductive pulse. It has been unknown, however, whether the analog of menstrual synchrony occurs in birdsthat is, whether avian ovulation cycles can synchronize on a daily timescale within the annual breeding pulse. We report every-other-day clutch-initiation and …