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May 15th Update--Broad winged hawks

by Bob Sallinger

kgw.com

Posted on May 15, 2009 at 7:03 PM

Updated Wednesday, Nov 4 at 2:39 PM

Happily back from D.C. after spending the night in the Philly Airport due to air traffic delays. I can see my postings about the Roller Pigeon cases have sparked some debate. I'll just say that these acts were flagrantly illegal and gratuitously sadistic. For anybody interested in reading more about them check out the Audubon Website, especially the National Audubon Magazine and Backpacker Magazine articles. What makes it all the more pathetic is that they bragged about the killings on their websites and the clubs tacitly condoned their behavior and continue to post lame justifications. I'll leave at that.

Now back to the red-tails. So they certainly are growing up fast! They are now 29 and 30 days old. However by bird standards their development is actually relatively slow. The following list gives the amount of time it takes for a variety of species to go from hatch to flight:
* Barn swallow: 18-23 days
*Anna's hummingbird: 18-23 days
* House finch: 18 days
*Robin: 16 days
*Mallard: 42-60 days
* Downy woodpecker: 20-25 days
*Western screech owl: 28 days
*Cooper's hawk: 27-34 days
*Bald eagle: 70-98 days
*Great blue heron: 56-60 days
*Crow: 28-35 days

Notice the shape of the wings that are developing. Red-tails are in a group of hawks known as "Buteos" or "broad winged hawks." These hawks are built for soaring rather than speed. They have big, broad, rounded wings to maximize wing surface relative to body weight. This allows that to easily stay aloft for long periods of time with minimal effort. Each of the outer primary feathers is able to move independently of the others almost like fingers. This allows the bird to make tiny adjustments to maximize its use of air currents. Other broad winged hawks found in the State of Oregon include rough-legged hawks and Swainson's hawks.

Two other groups of raptors found in Oregon are falcons and accipiters, Unlike the buteos, the falcons and accipiters are built for speed. Accipiters (which include sharp-shinned hawks, Cooper's hawks and goshawks) have short rounded wings and long tails that provided for a very high level of maneuverability and short bursts of speed. These hawks are typically found in forested areas and blast in and out of the trees taking birds on the wing. Falcons (which include kestrels, merlins, peregrines, prairie falcons and gyrfaclons) have long pointed wings. In a normal flight, they have to do far more flapping and expend more energy than buteos. However the pointed wings allow falcon to attain very high speeds in dives and these birds typically hunt other birds out in open country.


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