Cooper’s Hawks

Cooper’s Hawks are likely the commonest raptor found in Burnaby, but much of the time you wouldn’t know it. Like all members of the accipiter family (true hawks) they are specialized, bird hunting, ambush predators, that mostly remain hidden deep in cover from where they launch surprise attacks, and pursue their avian prey through the woods.

However, in July and early August when the young birds have just fledged (left the nest), they frequently perch out in the open for a few days, noisily begging for food. Recently, friends in North Burnaby phoned to tell me that they and their neighbours were being entertained by a family of four recently-fledged, and two adult Cooper’s Hawks in nearby Montrose Park.

COHAGroup

Three of four juvenile Cooper’s Hawks await their parents’ return with food – Montrose Park.

When I headed over there the next day, the birds seemed to have learned their first lesson as young raptors – stay hidden. No doubt the youngsters had been mobbed by smaller birds, and the neighbourhood crows, which will attempt to drive all raptors from their territory. But, while staying hidden, they were still calling loudly for food. After a bit of searching, and using their long, wheezing whistles to guide us, we finally managed to find a couple of the young birds perched, and begging for food in the deciduous trees along the Trans-Canada Trail through Montrose Park.

COHA#1

Juvenile Cooper’s Hawk concealed in big-leaf maple, begging for food

The adults were not  around when we were there, and were likely out hunting for the young birds’ next meals. Over the next two or three weeks the young will continue to be fed by their parents, but they will increasingly be left to their own devices until, and after four or five weeks, they will be abandoned to their make their own way in the world. If they haven’t honed their hunting skills sufficiently in the meantime, they’ll not survive. They may still hang around in the area of their birth up to six weeks after fledging. You should have a good chance of finding one if you head down to Montrose.

It’s a steep learning curve for the young Cooper’s Hawks to become independent hunters, but they’re born with all the equipment they need. Their incredibly sharp vision puts human  eyesight into the piker division. Cooper’s Hawks can not only resolve much greater detail at greater distances than humans, but they are also able the track the rapid movements of their prey through the forests, which for us would simply be a blur. Their binocular vision gives them the very precise judgement of distances which is essential for capturing fast-moving prey.

COHA#6

Forward facing eyes give Cooper’s Hawks a wide field of binocular vision, essential for hunting.

Cooper’s Hawks wings are relatively short and rounded, whereas their tails are relatively long. You can see in the picture above the long extension of the tail beyond the wing-tips. This combination makes them stunningly maneuverable in flight. Fast to accelerate, they are able to make incredibly sharp turns at very high speeds to pursue their prey through dense vegetation. And they often seem totally fearless when chasing down their quarry.  I recall watching one chase a starling from a bird feeder, and then crash full force into a dense shrub, into which the starling had plunged to make its escape, only to yank it out, clutched in one foot.

COHA#4

Long, sharp talons make for a deadly grip on the Cooper’s Hawk’s prey

Cooper’s Hawks are a success story in the urban bird world. Once in serious decline across North America due to hunting, pesticide contamination, and loss of forest habitats, they have now rebounded and adapted extremely well to urban environments, including our parks, where they find plenty of prey.

Andy Stewart in Victoria has had a long term program of banding and monitoring Cooper’s Hawks in the capital city, and he has discovered some of the highest densities ever recorded on the continent just across the Straight from us. I would not be surprised at all if we have comparable population densities of these beautiful predators right here in Burnaby.

Hawks banded in Victoria have been recorded a number of times on this side of the Strait of Georgia. Keep an eye out around your bird feeders this winter. Cooper’s Hawks often snatch their prey from our gardens.

To read more about Andy’s work, click here. A longer article, with a more continental perspective on Cooper’s Hawks can be found here.

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7 thoughts on “Cooper’s Hawks

  1. Hi, I see a bird that looks like one of these hawks on a regular basis, maybe once a week, perching on a street lamp on Gaglardi Way, right in front of Burnaby Mountain high school. Usually in the early afternoon.

    • Hi John,

      Could be Cooper’s for sure, but what you’re more likely seeing is a Red-tailed Hawk, especially if it’s sitting on a lamppost in a regular location. At some time in the future, I will be doing a blog post on Redtails in Burnaby. In the meantime, I’ll have to try to get a picture of the bird you’re seeing.

      Thanks,

      George

  2. We saw a hawk fittings this description near Duthie and Hastings near Burnaby Mountain but based on the some of the description it could be a Sharp Shinned Hawk, near my bird feeder.

    • It’s often very tough to separate these two species, and usually a combination of features clinches the identification one way or the other. Cooper’s Hawks are much, much commoner than Sharp-shinned, and both take advantage of the “offerings” at our bird feeders.

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