Cooper’s Hawks Nesting in the City
Cooper’s Hawk ©Jim Dunn
Several years ago, Cooper’s hawks began to nest in my part of Davis. I surmised that these previously winter-only birds waited till there were trees tall enough to suit their nest site requirements. This year two pairs nested near my home, one in Slide Hill Park and the other about four tenths of a mile to the south. Between them they fledged five young, who were conspicuous by their endless screaming until early in August, when they disappeared from view.
Their presence meant that the neighborhood had to supply enough food for nine bird-eating hawks for more than three months. My regular surveys of the area hinted at which birds were on the menu. I watched as several species, mostly medium-size songbirds, became much scarcer from late spring into summer.
The most obvious loss was among the local scrub-jays. At about two pairs per city block, they produced numerous fledglings, only to have nearly all of them disappear in short order. A couple of years ago I watched as the local male Cooper’s plucked large nestling jays from a nest as their parents watched in silence.
A mockingbird sang every night, seemingly all night long, well into spring, almost directly outside my bedroom window. I wanted badly to shut him up and—horrors—got my wish when one night in May he and his serenade abruptly went missing. I assume he lost his life earlier that day.
A pair of California towhees took up residence on my block early in the year (the first of the species ever to do so) and made a nest, which failed. Abruptly in mid-summer the female disappeared, and the now unmated male began to sing, advertising for another mate. Within two weeks he was suddenly gone too. It seems that my block is not a good place for California towhees. The Cooper’s hawks probably caught these confiding birds, though a local cat may have been the culprit.
Three or four pairs of western bluebirds nested in boxes in the neighborhood, and all fledged several young. But by early August I could hardly find a bluebird in the area. Notably, by the end of that month I began to see them again. Hopefully they were returning survivors. Lastly, a ridiculously tame pair of mourning doves frequented the yard all year, well into summer, until they, too, went missing.
Records in eBird from April and May of this year suggest that there could be easily a dozen pairs of Cooper’s hawks nesting in Davis, and several pairs each in Woodland and West Sacramento, all likely with similar diets. The true numbers are probably obscured by differences in birding effort among cities. Remarkably, Vacaville and Fairfield had hardly any sightings in the same period. That’s a puzzle.
— Michael Perrone, Conservation Chair