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Cross Timbers Wildlife News - Jim Dillard
March 2003



Jim Dillard is a Wildlife Biologist for Texas Parks & Wildlife. He writes from Mineral Wells TX.

Blue Darters

When the persistent sound of chirping house sparrows was silent the other day in my backyard, I knew something was definitely wrong. I wasn't sure if we were fix'en to have an earthquake or the mob of sparrows had miraculously left, which wasn't likely since they'd been emptying my bird feeders on a daily basis for the last month - there was just overwhelming silence. Suddenly, a blue streak flashed from overhead into the shrubbery and sparrows went in all direction, all except one, that is. It had just become dinner for a sharp-shinned hawk that was on the prowl through the neighborhood. After it left with its carry out lunch, I tried to thrash the rest of the sparrows out the bushes with a broom, but they wouldn't budge until they were sure the coast was clear.

Nothing brings more terror to small birds than the sight or swooshing sound of a sharp-shinned (Accipiter striatus) or Cooper's (A. cooperii) hawk (a.k.a. blue darters) on the hunt. These two species belong to a group of hawks called accipiters. They're sorta like the United States Air Force's F-16 Fighting Falcon of the hawk world, known for their stealthy strafing raids and sneak attacks. But blue darters don't conform to the Rules of Geneva Convention when it comes to small birds - they take no prisoners.

Sharp shins are primarily winter visitors here in North Texas and will leave during the spring to nest in northern and western North America. Cooper's hawks are more widely distributed in the state and their population increases during the winter. They nest from southern Canada into northern Mexico and throughout much of Texas except on the High Plains.

These small hawks are built for speed and maneuverability, using the tails like rudders and short rounded wings to dart and weave through the branches of trees and brush to pursue their prey. Small birds that don't get to cover quickly or see one coming aren't long for this world. Even on the wing, they can overtake most small birds in a hurry, grabbing them in mid-air with their talons before they know what hit them. They prefer to hunt in wooded or brushy areas and seldom venture out into open fields or prairie country. They'll cruise low over trees, hoping to surprise and flush unsuspecting birds or perch motionless in trees, just waiting to bushwhack small birds when they get to close, and then the chase is on which they usually win. Rats, mice, bats, reptiles, grasshoppers and other larger insects round out their diet.

Sharp-shined hawks are very similar in appearance to Cooper's hawks, making field identification difficult for most folks, including me. Remember, these are small hawks, not like the big puffed-up red-tailed hawks you see sitting on trees or fence post. Feather coloration of adults is about the same for both species - blue-gray on the back and wings with rusty barring across the white undersides. Immature birds are brown with brown streaks on their breast and belly. The tail of the sharp shin is short, square-tipped or notched and has 3-4 narrow black crossbars. In flight, the tail of a Cooper's hawk appears longer and rounded with black barring and a wide white band at the tip. The head of a sharp shin looks disproportionately small for its body size and lacks the dark crown of the Cooper's. Size-wise, sharp shins are 10-14 inches long and weigh about 3.6 oz., whereas Cooper's average 14-20 inches and weigh 12.3 oz. Females of both species are a little bigger than males. They also have distinctive bright yellow legs and feet, and the shins of sharp shins are sharp (no kidding, it's in the book). Their calls are something like kek-kek-kek-kek or kac-kac-kac-kac.

Both parents help build a stick nest and line it with strips of bark, grass and leaves. The female lays 4-5 white eggs and does most of the incubating for the 32-36 days it takes them to hatch. Young are then fed by both parents for 4-5 weeks.

The Cooper's hawk often assumes the moniker "chicken hawk" and an occasional bobwhite or barnyard fowl will bite the dust. Some individual hawks are more inclined to prey on certain critters rather than others. This feeding preference is thought to be a learned response from early successful hunting experiences, so maybe "once a chicken- hawk - always a chicken-hawk" or "once a finch-hawk - always a finch-hawk." Both species are protected by several state and federal laws and may not be killed, taken from the nest, picked up, or possessed for any reason, and their feathers may not be possessed or sold either.

Good land management practices that provide adequate habitat and cover throughout the year go a long way toward reducing losses of gamebirds and songbirds to predators. Couch-potato barnyard birds will always be "sitting ducks" for blue darters every now and then. Quail feeders are like magnets to these aerial opportunists, often luring unsuspecting birds out into the open and right onto the radar screen of a waiting blue darter. Putting up a backyard bird feeder is like ringing the "dinner bell" for sharp shins and it doesn't take them long to figure out who's coming to dinner. I'll sacrifice a few house sparrows from my backyard every now and then just for a glimpse of a blue darter - dinner is served!

Until next time - I'll see you down the road and God Bless America!



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