This morning, we visited the colony of common murres that nests on the rocks just off Yaquina Head. Offshore islands make good sites for nesting seabird colonies because shore-based predators such as foxes, cats, and rats can't access their nests and eat their eggs or chicks.
Space is at a premium, and the tops of the colony islands often appear to be a mass of black and white. The bottom two photos are what we typically expect to see during the nesting season.
The main colony rock was densely populated on the south end, but sparsely populated at the north end (middle 2 photos). If you look closely, you will discover the reason that the murres had abandoned their nests -- a large adult bald eagle. While nests on the rocks are safe from terrestrial predators, flying predators such as bald eagles, and the opportunistic gulls that move in after them, can decimate breeding colonies.
A juvenile bald eagle was low on the big colony rock, and many murres could be seen in the water around the rocks (top 2 photos).
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