In our Backyard…
In late February a pair of Cooper’s Hawks made their home at the north end of the Inland Empire Utilities Agency (IEUA) campus. Staff had found that the Hawks produced 2 eggs in their nest. Around early May staff had noted that the two young hawks started peaking over the nest. Since the nest was in close proximity to the Agency’s parking lot a warning needed to be sent to staff to be aware of the aggressive female hawk protecting her young.
Among the bird world’s most skillful fliers, Cooper’s Hawks are common woodland hawks that tear through cluttered tree canopies in high speed pursuit of other birds. You’re most likely to see one prowling above a forest edge or field using just a few stiff wingbeats followed by a glide. With their smaller lookalike, the Sharp-shinned Hawk, Cooper’s Hawks make for famously tricky identifications. Both species are sometimes unwanted guests at bird feeders, looking for an easy meal (but not one of sunflower seeds).
Dashing through vegetation to catch birds is a dangerous lifestyle. In a study of more than 300 Cooper’s Hawk skeletons, 23 percent showed old, healed-over fractures in the bones of the chest, especially of the furcula, or wishbone.
A Cooper’s Hawk captures a bird with its feet and kills it by repeated squeezing. Falcons tend to kill their prey by biting it, but Cooper’s Hawks hold their catch away from the body until it dies. They’ve even been known to drown their prey, holding a bird underwater until it stopped moving.
Once thought averse to towns and cities, Cooper’s Hawks are now fairly common urban and suburban birds. Some studies show their numbers are actually higher in towns than in their natural habitat, forests. Cities provide plenty of Rock Pigeon and Mourning Dove prey. Though one study in Arizona found a downside to the high-dove diet: Cooper’s Hawk nestlings suffered from a parasitic disease they acquired from eating dove meat.
Life is tricky for male Cooper’s Hawks. As in most hawks, males are significantly smaller than their mates. The danger is that female Cooper’s Hawks specialize in eating medium-sized birds. Males tend to be submissive to females and to listen out for reassuring call notes the females make when they’re willing to be approached. Males build the nest, then provide nearly all the food to females and young over the next 90 days before the young fledge.
- The oldest known Cooper’s Hawk was 20 years, 4 months old. (allaboutbirds.org)http://www.allaboutbirds.org/guide/Coopers_Hawk/lifehistory