Hawks Aloft Inc.
PO Box 10028
Albuquerque, NM 87184
Phone: 505 828-9455
Fax: 505 828-9769
E-Mail: gail@hawksaloft.org

Logo: Hawks Aloft Inc.

Hawks Aloft Blog

How to Age Cooper’s Hawks

Cooper’s Hawk in flight, displaying the long, rounded tail characteristic of the species. Image by Doug Brown.

We were thrilled to receive a new set of images from photographer Doug Brown this past weekend.  He had been photographing migrating  raptors along the Texas Gulf coast and snagged some great shots.   The hawk in the image above  is a second year bird.  While the hawk has mostly the gray feathers of the adult, as well as the rufous color on the breast, some brown feather remain on the back.  Juvenile Cooper’s Hawk have brown backs with some white spots on the upper back.  They molt into the adult plumage with a solid gray back during their second summer.   This bird also shows a yellow-orange eye color which is indicative of age in all accipiters.  However, the rate of change in eye color is variable and cannot be used to definitively age an accipiter.

 

Cooper’s Hawk displaying the attributes that characterize the species: short, rounded wings and a long tail. Image by Doug Brown.

Cooper’s Hawks belong to the accipiter family, also known as ‘forest’ hawks.  All three North American species, the Sharp-shinned Hawk, the Northern Goshawk, and the Cooper’s Hawk, have similar body shapes and are adept at pursuing prey through dense vegetation.  Cooper’s Hawks are primarily bird-eaters, although they also take small mammals and insects.

Cooper’s Hawk close up. Image by Doug Brown.

In the above image, a few brown juvenile feathers remain on the bird’s back.  Additionally, the gray ‘cap’ that is characteristic of the adult Cooper’s Hawk is not yet complete, also identifying this bird as being in its second summer.  Note the eye color on this hawk is still yellow.  Cooper’s Hawks have a prominent supercilliary bony ridge above their eyes as do Northern Goshawks.  The Sharp-shinned Hawk lacks the bony protrusion, giving it a bug-eyed appearance.

Adult Cooper’s Hawk. Image by Doug Brown.

The above image shows an adult Cooper’s Hawk with a solid gray back and a pronounced gray cap on its head.

Juvenile Cooper’s Hawk. Image by Doug Brown.

Finally, here is a juvenile Cooper’s Hawk with the typical brown back with white spots, the light-colored head, and the very pale eye color.  It is important to remember that eye color alone cannot be used to accurately age any accipiter.

5 Responses to “How to Age Cooper’s Hawks”

  1. Susan Leonard says:

    On our porch was a scrunched up hawk , brown w/white circles on its back ….it flew off when I tried to take its pic. I think it was a juvenile Cooper’s hawk. I think it flew into our window and was stunned by the impact

  2. Paul Schambers says:

    I live in Parkland Hills, where I’ve had a hawk visit my bird feeder for a number of years, but not this year. Nor have I seen nor heard the hawk at Hyder park nor Altura park. Am I there at the wrong time or are they gone?

  3. Derrick J. says:

    I just witnessed a yellow eyed Cooper Hawk catch a small bird outside my window. I have a bird feeder and I noticed something larger than normal in my side view. They are very majestic and quite interesting. And when he’s near birds and squirrels dissappear suddenly. But I did nothing to help the bird the hawk caught cause it to late anyway

  4. Chloe says:

    Keep up the good work on hawk eyes, you may find more info in the future

  5. Jerry says:

    Cooper’s Hawks built nest in yard about a month ago. When do juveniles begin flight?

Leave a Comment