Migrations: Pine Siskin Irruption

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Pine Siskin Irruption

Written by Ariana Remmel

This is BirdNote.

Do you ever see flocks of birds in your yard that show up in droves one year but are completely absent the next? 

[Pine Siskin songs]

Take this flock of Pine Siskins swarming around a thistle feeder, their wings briefly flashing yellow as they flit about. Rather than adopting the common, north-and-south itinerary you might associate with migrating songbirds, these siskins take a more nomadic approach — their movements depend on the availability of food and habitat. It’s called “irruptive” migration.

[Pine Siskin songs]

In years when conifer seeds are scarce in the boreal forests of Canada, Pine Siskins might hang around in lower latitudes — say Southern California or Tennessee. The location and timing of these irruptions change from year to year. 

And sometimes by chance, gigantic flocks of Pine Siskins get funneled into the same regions — leading to backyards full of siskins. While these flocks are a delight for bird watchers, the dense groups of siskins can easily transmit diseases such as salmonellosis to each other and to other birds. It’s a good reminder to keep bird feeders clean for our feathered visitors that can’t always “social distance” when diseases spread. 

[Pine Siskin songs]

For BirdNote, I’m Ariana Remmel. 

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Bird sounds provided by The Macaulay Library of Natural Sounds at the Cornell Lab of Ornithology, Ithaca, New York. Pine Siskin ML 304501831 recorded by M.Z.
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© 2021 BirdNote      October 2021    Narrator: Ariana Remmel
ID# PISI-01-2021-10-08     PISI-01