Wednesday, March 28, 2012

A Pair of Cooper's Hawks

immature Cooper's hawk in the rain
It is official, the Cooper's hawks are trying to start a family. 

For three hours on Sunday, an immature Cooper's hawk sat on the power line above our bird feeders in the rain. The bird did not seek shelter and looked a bit soggy with a drop of water dripping every few minutes from its beak.

Last year a pair of Cooper's hawks successfully nested in a large jacaranda tree about a block away. This year an immature individual began hanging around about a month ago and was occasionally seen with a mature bird. The immature Cooper's hawk pictured here does not yet have the distinctive gray cap and back of an adult. It is still more brown in coloration around the head and shoulders. Notice the banded tail typical of Cooper's and sharp-shinned hawks. These fast maneuvering hawks are bird predators and their appearance in the yard has disgruntled the band-tailed pigeons.

young female Cooper's hawk
I wasn't quite sure of the relationship between the two Cooper's hawks, but yesterday it all became clear.

The immature or young hawk is a female and the adult is a male. He brought her a mourning dove yesterday to seal their relationship and prove his ability as a provider. She accepted the dove and his sexual advances. Occasionally, I see one or the other of them fly past the window with a stick or pine bough. They are building a nest, but I haven't spotted the location yet.

If you are noticing nesting birds in your area, take a minute and consider documenting the nesting attempt on Cornell University's NestWatch website. Scientists can't be in everyone's backyard, but you can play an important roll for scientists; be their eyes, ears and observers. 

The Bewick's wrens were back working on their nest in the lariat house yesterday. And I'm still searching for a hummingbird nest; there have been starts and stops due to the rainy weather. Follow the daily progress of your nesting birds. You'll be surprised by their daily dramas and joys. Document it all with just a few minutes every 4 days and you'll play an important roll for science.

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