Piracy Among Raptors

BirdNote^®

Piracy Among Raptors

Written by Bob Sundstrom

This is BirdNote! [Whistled calls of a Northern Harrier]

It’s early morning, and the winter sunrise bathes the horizon in pink. A Northern Harrier – a lanky, low-flying hawk – systematically covers a broad expanse of open ground. The harrier flies slowly on canted wings, hunting just a few feet above the grass-covered earth. [Call of a Northern Harrier] With a sudden, mid-air twist, it slams its talons toward the ground, catching an unwary rodent.

Just as the Northern Harrier lowers its head to partake of its quarry, a swift Peregrine Falcon streaks in on long, angled wings, knocking the harrier off its still-warm prey.

By snatching the harrier’s first morning meal, the falcon saves itself the time and effort of foraging. Biologists call this behavior piracy, or kleptoparasitism.

It’s a scene repeated in many areas across North America where birds of prey congregate in winter. In truth, piracy is almost routine – as our Peregrine Falcon is about to find out. Because just as the falcon took from the harrier and is now about to dine, a massive Bald Eagle – which had watched the entire drama unfold – flies in from a nearby perch to relieve the falcon of its already-once-purloined prey. [Call of Bald Eagle]

The eagle had better eat quickly. Other eagles are watching. [Calls of two Bald Eagles]

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Call of raptors provided by The Macaulay Library of Natural Sounds at the Cornell Lab of Ornithology, Ithaca, New York. Northern Harrier recorded by W.W.H. Gunn; Bald Eagle individual and pair, recorded by J. Storm.
Padilla Bay ambient recorded by C. Peterson
Producer: John Kessler
Executive Producer: Chris Peterson
© 2015 Tune In to Nature.org   January 2017 / December 2022   Narrator: Michael Stein

ID# piracy-01b-2010-01-07-MS