Tuesday, May 5, 2015

Haystack Rock Predators

Have you ever been quietly observing the tidepools at Haystack Rock when all the birds suddenly start squawking and they all seem to take to the sky at once? This is a sure sign that the predatory birds that frequent the rock are on the hunt. Haystack Rock is frequently visited by Bald Eagles, Peregrine Falcons, and occasionally by Osprey. The predators most common prey is the Common Murre (Uria aalge). Occasionally, they will take an adult cormorant, but more commonly they will take eggs from a unprotected nest after the parent bird flees it upon the arrival of the predators.


Birds taking to the sky in response to the arrival of a predator
Photo Courtesy of Susan Glarum

There are two pair of bald eagles (Haliaeetus leucocephalus) that regularly frequent Haystack Rock. Eagles build large nests, predominantly in tall, sturdy conifers; one of the pair that visits Haystack Rock lives in the forest to the east of Cannon Beach and the other pair is usually seen flying away to the south. Both male and female bald eagles have a blackish-brown back and breast; a white head, neck, and tail; yellow feet, legs, and beak; and pale yellow eyes. Immature bald eagles do not have the distinctive white head and tail, nor do they have a yellow beak or eyes; these traits develop as the bird matures over it first 5 years of life. A female bald eagle has a wingspan of 79 to 90 inches; the male is smaller with a wingspan ranging from 72 to 85 inches. An eagle's average weight is between ten and fourteen pounds. Bald eagles are birds of prey, at the top of the food chain, and will predate on other birds, fish and will take advantage of carrion. Listed for many years on the Federal List of Endangered and Threatened Species, the bald eagle was removed from the list in 2007 but is still protected under the Bald and Golden Eagle Protection Act.


Bald Eagle perched on Haystack Rock
Photo Courtesy of Susan Glarum

Peregrine Falcons (Falco peregrinus) also visit Haystack Rock, usually alone and typically not as frequently as eagles. They are a smaller bird than the eagle, with a wingspan between 30 and 45 inches, and, like most raptors, the males are smaller than the females. They are blue-gray on the back with a 'barred' pattern in shades of brown on the breast, and have long, pointed wings and a long tail. The peregrine is a very fast flyer and catches its prey, typically medium-sized birds, in mid-air following a swift dive. The peregrine nests on cliff ledges, and in the Pacific Northwest they may also nest among or under Sitka Spruce tree roots on steep slopes.


Peregrine Falcon Circling ...
Photo Courtesy of Susan Glarum


 ... and Diving
Photo Courtesy of Susan Glarum

Next time you visit Haystack Rock, sit in the sand and observe the birds inhabiting the monolith - you might just witness a visit by one of the resident birds of prey! HRAP frequently has spotting scopes set up on the beach - be sure to take a look and talk with the interpreter about the wildlife at Haystack Rock! HRAP Interpreters are on the beach every day at low tide.

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