Sunday, July 18, 2010

More about the cemetery hawks

I'm fascinated by the Cooper's hawks (Accipiter cooperii) at Santa Rosa Rural Cemetery. Although this species' natural habitat is forests, Cooper's hawks have found the suburbs to be an excellent place to live and raise a family. Their main source of food is other birds and they prefer larger birds, which explains why I've seen several small songbirds perched, with what seemed to be an astounding lack of concern, near the hawks on several occasions. Doves, pigeons, jays and robins are among their preferred meals but they also eat small mammals. In fact, they have become regular visitors at some backyard bird feeders, where the hunting is easy.

Cooper's hawks hunt by flying fast, through the trees, taking their prey by surprise. However, one recent study showed that it's a dangerous way to hunt. According to All About Birds a study revealed old healed fractures in the chests of 23% of more than 300 Cooper's hawk skeletons.

The male is much smaller than the female and submissive to her. When it's time to mate he waits for her vocal encouragement before approaching. It's his job to build the nest then feed her and the nestlings until they fledge.

Cooper's hawks migrate south for the winter which explains why I didn't start seeing the mated pair until April this year.

All About Birds
Project Feeder Watch

1 comment:

  1. My mother, Frances Hamerstrom, published several scientific papers on raptors. I remember her making notes on how birds were much more brazen about harassing her red-tailed hawk when the redtail was well fed. When the hawk was 'sharp set,' i.e. hungry, the little birds kept a wider distance. Perhaps the birds you saw get close to the Coopers knew it had eaten recently.

    Wonderful sketch of the Coopers in the woods!