
13 October 2023
When peregrine falcons migrate down the Pacific Coast in autumn they steadily pause at Canada’s Fraser River Delta to seek shorebirds. Pacificnorthwestkate (@pnwkate) filmed one operating a sandpiper flock at Roberts Financial institution.
Sandpiper Murmuration at Roberts Financial institution
My hyperlinks – https://t.co/hR2LPCrpM4 #birds #nature #natural world #stopRBCT2 #murmuration #sandpipers %.twitter.com/VwJEiU6naC
— Pacificnorthwestkate (@pnwkate) October 12, 2023
Peregrines at the hunt hope to split a unmarried hen from the group as a result of they can’t catch anything else in one of these tight flock. When a lone hen can’t stay up it turns into the peregrine’s dinner.

Dunlin flocking habits at the Pacific Coast modified after the peregrine inhabitants recovered within the Nineteen Nineties. A learn about on the Fraser River Delta in 2009 discovered that dunlin temporarily discovered it used to be unsafe to roost at prime tide throughout the day as a result of peregrines had been on patrol. As an alternative they started to spend prime tide flocking over the open ocean, flying incessantly for 3 to 5 hours.
A brand new learn about, revealed this month in Phys.org, appeared on the interplay from the peregrines’ standpoint and located that the falcons haze the dunlin flocks to stay them transferring. Peregrine looking good fortune advanced on the finish of the ones 3-5 hours of constant flying since the dunlin needed to forestall for a leisure.
The looking information confirmed that dunlins had been at largest possibility of predation simply earlier than and simply after prime tide, and spent lots of the riskiest length flocking. Then again, there used to be a pointy build up in kills two hours after prime tide, since the dunlins weren’t flocking in spite of increased possibility. [They were resting.]
So the dunlin modified their habits to steer clear of peregrine predation and the peregrines modified their habits to wear down the dunlin. Peregrines have extra stamina that dunlin.
Learn extra concerning the peregrines’ looking technique at Phys.org: Peregrine falcons spark off false alarms to make prey more straightforward to catch, learn about reveals.
(credit and hyperlinks are within the captions)