http://komonews.com/news/local/climate-change-may-be-turning-washingtons-gul
ls-into-cannibals

An excerpt from the article:
"It doesn't seem like a lot, but a one-tenth of a degree change in seawater
temperature correlates to a 10 percent increase in (the odds of)
cannibalism," said Hayward, a professor at Andrews University in Michigan.

Over the past 60 years, ocean temperatures have increased about 15 times
faster than any other time over the past 10,000 years. As temperatures rise,
plankton drops into deeper, colder water. Fish that feed on the plankton
also drop lower. The surface-feeding gulls, which depend almost entirely on
fish while nesting on Protection Island, can't find enough to eat.

"So they resort to feeding on their neighbors," Hayward said.