FOAM LAKE BIRDING
No. 94
This morning, as we were having coffee and watching three robins and a family of six flickers vying for positions on a power pole, a Coopers Hawk flew by scattering all the birds in the vicinity save for the flickers. The flickers seemed unafraid, perhaps because of their large size and powerful beaks. A Coopers Hawk could suffer some severe damage from tackling such a bird. This incident provided me with the topic for this week's article. I also realized that I had covered only one family of hawks before, the kites, which do not occur here. This oversight will be corrected right here and now.
The hawks are divided into several families each of which has its own unique characteristics. The Coopers Hawk belongs to a family of hawks called Accipiters, sometimes referred to as bird hawks. There are other individual species of hawks that prey on birds, but this is the only family of hawks to do so. Being birds of forests and woodlands, they are designed to succeed in this environment, and these adaptations can be used to identify accipiters quite easily, especially in flight. The wings are broad and short, more paddle-like than those of other hawks. The tail is long giving the accipiters a rather long tailed look. Both, the wings and tail, are designed to help the hawk fly with great speed and agility through dense woods in pursuit of prey birds. The easiest way to identify this family is by its flight pattern of four (usually) quick flaps of its wings followed by a short and swift glide. When one comes flying by small birds literally dive for cover.
There are three species in the accipiter family: the chicken sized Goshawk, the crow sized Coopers Hawk and the robin sized Sharp Shinned Hawk. The Goshawk (goose hawk) is a bird of larger forests, but in the fall and winter can occasionally be seen locally. The Sharp Shinned is the most common of the three and often comes into town to catch birds at feeders. Several years ago a Sharp Shinned made a catch and ate the bird right under our Chokecherry trees. Its close cousin, the Coopers Hawk, was the bird that liked to prey on young chickens in farmers' yards thus earning the nickname of chicken hawk. Unfortunately, the Coopers Hawk gave all hawks a bad reputation resulting in indiscriminate shooting of all hawks. Thankfully, killing any hawk at any time, except to protect livestock, is illegal now.
Like most hawks the males and females are the same, and like all hawks the females are larger and more powerful than the males. In this last regard. hawks are the exception as the males are usually larger than females in the animal world. Sharp Shinned Hawks were the most populous of the three, but it appears that the Cooper is now gaining ground and seems to be on par with the Sharp Shinned.
All three accipiters are very similar, but the Coopers and Sharp Shinned are almost identical. Furthermore, a large female Sharp Shinned and a small male Coopers are almost the same size thus adding to the confusion. There are differences but they are very subtle and require a sharp and practised eye to discern them. In this piece I will deal with only one, and what I consider the best, field mark that is useful in identifying a perched bird. The Coopers Hawk has a rather dark cap while the Sharp Shinned's head is all grey. Binoculars are a must, For a full discussion on field marks for these two hawks refer to a good bird book.
This week's photo is of a juvenile Coopers Hawk taken in California where they are common. A juvenile is brown and white with brown stripes on a white breast and belly. The adult has orange bars on a white breast and belly, a handsome bird.
On a final note, I want to point out that the grosbeaks in the 92nd article were mislabelled. The Rose Breasted Grosbeak was labelled as the Black Headed and vice versa. The names should have been reversed. Hopefully this clears up any confusion.
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