When I started birding in the late forties, there were still lots of farms with areas enclosed by chicken wire where chickens ran around in the open during the day before roosting in the adjacent chicken coop at night. A hawk that might fly into the yard and take one of these chickens was a "chicken hawk."  Contemporaneously, National Audubon was making mighty efforts to teach farmers that Red-tailed Hawks were rodent eaters, not chicken hawks. Part of the education then going on (I'm not sure specifically by NAS) included telling the public that only one hawk could rightfully be called a "chicken hawk," and that was the Cooper's Hawk.
One product of that education was that, when I moved to Missouri in 1972, Red Tails were (as they are today) very common, but Cooper's Hawks were relatively rare. For the first few years of birding, I usually had less than a half dozen sightings of Cooper's Hawk annually during my birding in western Missouri and eastern Kansas. Today, I probably have 25 sightings a year, including during summer in my home town of Independence. I saw one zoom through my back yard last week.
Strictly speaking, the farmers who called Red-tails "chicken hawks" may occasionally have been right because NAS was overlooking the fact that Red-tailed Hawk diets include birds and reptiles in addition to rodents. NAS' basic point was, however, valid. Red-tails do a lot more good by eating rodents than they have ever done harm by occasionally taking a free ranging chicken.
Today, chickens spend their whole lives inside long buildings. Even those whose eggs are labeled "free range" are reputed to have access only to tiny spaces outside gigantic buildings. (If he can find his way past thousands of birds inside the building, locate the opening to the outside area and step outside for a breath of fresh air, has he not "ranged free?")
There are no more real chicken hawks.
Bob Fisher
Independence, MO
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The Audubon Society of Missouri's Wild Bird Discussion Forum
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