early bird

Allen Hurlbert and Zhongfei Liang used more than 48 million observations from amateur birdwatchers to conclude that every 1.8-degree rise in temperature makes birds reach their migration milestones 0.8 days earlier on average (though much more for some species in some locations).

That’s less than 11 hours per degree, so who gives a titmouse’s mouse tit? Well, birds do, or would if they had brains big enough to contain a large-scale self-preservation instinct.

Says Hurlbert: Timing of bird migration is something critical for the overall health of bird species. They have to time it right so they can balance arriving on breeding grounds after there’s no longer a risk of severe winter conditions.

If they get it wrong, they may die or may not produce as many young. A change in migration could begin to contribute to population decline, putting many species at risk for extinction.

CounterCurrents.org, 4 Mar 2012