Animals Migrate North as Globe Warms

Salmon swim north into Arctic seas, locusts plague northern Italy and two heat-loving bee-eater birds nest in a hedge in Britain.
Signs of global warming fed by greenhouse gases produced by human activity, or just summertime oddities?
In the United States, some warblers are flying north to Canada. In Costa Rica, toucans are moving higher up into the mountains, apparently because of rising temperatures.
In July, a Norwegian man fishing in a fjord had a shock when he landed a John Dory, a fish more usually found in temperate waters off southern Europe or Africa.
"There's a long list of migratory species ending up further north. It's certainly a sign of warmer temperatures," said Steve Sawyer, climate policy director at the Greenpeace environmental group.
He said salmon had been swimming through the Bering Strait between Alaska and Russia into the Chukchi Sea, apparently because the frigid water had warmed up.
Such shifts could have vast long-term implications for farmers and fishing fleets.