Sharp-shinned or Cooper's Hawk

When watching a bird through the lens there is no doubt I am a better photographer than ornithologist. Like many other folk I can easily do eagles & osprey, crows and robins. Ah! Hummingbirds, no problem. But even with so common a cluster of bird there are many a differential feather between them. Are they juveniles, immature, male or female, molting or not. The criteria list goes on and on. Not only have I a number of field guides to assist my limited knowledge, but on-line resources open a vast array of research opportunity. So why then is it so hard to determine one hawk species from another? And here I am speaking specifically about two hawks that commonly appear in the Okanogan and Columbia Highlands the Sharp-shinned and Cooper’s hawks.  After a lot of research and work with on-line birder groups I am landing the id of the birds pictured here as Sharp-shinned hawks, but I don’t expect everyone to agree with that decision, especially after the opening sentence.

A blur of motion, a flurry of feathers and then its gone! A Sharp-shinned hawk has struck again. This tiny, fast and highly acrobatic flier is the smallest hawk in North America. The general make-up of this diminutive  accipiter is noted as “long legs, short wings, and very long tails, which they use for navigating their deep-woods homes at top speed in pursuit of songbirds and mice.” In the image of the Sharpie here with the American robin in it’s clutches the raptor appeared to have used my presence as a distraction and when the robin bolted from me the hawk boldly nailed it within twenty feet of where I was standing. For a moment I was as surprised as the robin, though not mortally so.

Sharp-shinned like many other hawks declined during the DDT pesticide years but rebounded after the insecticidal chemical was banned. The populations of Sharp-shinned Hawk have remained stable with some growth from the early 1970s according to data from the North American Breeding Bird Survey. Still  scientists have little data on their nesting success given the solitary and elusive nature of these small hawks in their deep-forest breeding sites. Populations estimates from annual migration counts puts breeding pairs of these birds near 700,000.

Sharp-shinned Hawks are birds of the forest and prefer a dense, closed canopy, for breeding and nesting. In our highlands regions these birds favor conifers forests but intermix throughout the river and stream valleys in cottonwoods and aspens. The habitat range of elevations varies from sea level to near timberline.
Some interesting points regarding this species;  while atypical in the general world of avians (though common amongst raptors) female Sharp-shinned Hawks exceed the size and weight of males by about 1/3. This size difference plays a role in the raising of the hatchlings as it is the male that feeds the nestlings, given the smaller size of prey captured and the female that feeds the same young in their larger juvenile stage. And uniquely the male sharpie bites off and eats the head of prey before sharing the meal.  Another behavioral trait of some raptors found in adult Sharp-shinned Hawks is how they continue to feed the juveniles for several weeks after they have fledged. The parents deliver dead prey into the nest leaving the young to squabble and consume. Later the parent approaches and calls triggering the fledglings to rise to grab prey out of its parent’s claws. As the fledglings develop flight skills, the parents cease feeding at the nest and force the juveniles to pursue in flight with rewards of morsels. In such ways the skills of an aerial predator are achieved.

Its estimated that the Sharp-shinned Hawk’s diet is 90% songbirds. As pictured here birds the size of robins, warblers, sparrows, and thrushes are the most frequent prey. Bigger birds such as quail, doves, swifts, woodpeckers and the like are not completely safe from this little raptor. Adding to the diet are mice, voles, chipmunks and grasshoppers.
To observe these unique hawks closely watch the forest edge. Keep a sharp eye out for a dash of feathers flying fast and low, following the contour of the ground. Look into the foliage for that poised shape awaiting to spring on their prey. And don’t be too surprised if a Sharpie whizzes past your ear and takes down another bird in flight. It does happen…


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