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Yesterday a flock of Starlings flew into our yard, oddly accompanied by several woodpeckers. The woodpeckers were mostly Flickers, who investigated an old power pole (probably disappointing to them because it is treated wood). There also was a pair of Hairy Woodpeckers, each almost as large as the Flickers. Wedge Island. This is the nesting ground for Herring Gulls and Great Black-back Gulls, and this year also the Common Tern. It has been for the last five years or so invaded by Double-crested Cormorants, who have killed all the spruce trees in which they were nesting (which is all of them). Cormorant numbers increase each year, and this year they have started nesting also on the ground, and have obliterated all vegetation in those areas. I roughly estimate that the number of nests increases by about a third each year. Although the cormorants are apparently unstoppable, they do have some natural enemies. The gulls (particularly the Great Black-backed Gull) harass the young, causing them to panic in large mobs, and regurgitate their food. The gulls then eat up the resulting delicacies. And then at this time in the season, for the second year, the Bald Eagles have arrived. They apparently eat young cormorants and gulls. I don't know whether they actually kill them, or just scavenge the dead from other causes; but when the Eagles arrive, the cormorants and gulls who are able disappear from the island. Only a few Herring Gulls remain to dive occasionally (and ineffectually) at the Eagles. Quite a large number of eaten cormorants can be found (wings and large bones left behind), and also remains of young gulls. It is impossible to tell if the hunters were Eagles or Great Black-backed Gulls in each case, but there is a considerable mortality from the predators. No potential mammalian predators have been seen on the island by me, except about eight years ago (one muskrat).
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