Winter Bird Irruptions
According to the predictions on eBird’s annual Winter Finch Forecast, several species of northern seed-eating birds will be moving south this season due to a poor cone crop in the north. As of mid-October, pine siskins (pictured), purple finches, red-breasted nuthatches and red crossbills have already been showing up in larger numbers than usual in New England, well south of their normal wintering grounds. This type of movement is referred to as an irruption. Because of a widespread crop failure of fruiting and cone-bearing trees in Canada, we may be lucky enough to have a glimpse of crossbills, redpolls, pine grosbeaks and evening grosbeaks this winter. The latest to arrive at my feeders are pine siskins, whose irruptions often occur on a two-year cycle. Their numbers in New England were great during the winters of 2008 and 2010, so the pine siskin irruption this year is right on time.
Naturally Curious with Mary Holland 
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