Earth Notes
4:00 am
Wed May 16, 2012

Earth Notes: Osprey

They’re sometimes called fish eagles, for good reason: their diet is almost all live fish. They’re big raptors, hard to miss soaring above the scattered rivers and lakes of the Southwest’s high country. They’re ospreys, birds that belong to the summer skies of the Colorado Plateau.

With a six-foot-wingspan, snow-white belly, and dark wrist on crooked wings, ospreys are hard to miss. They return to the Southwest each spring from wintering grounds in Mexico and Central America. Upon arrival they go right to work building, or remodeling, bulky nests of twigs high in old ponderosas—or on top of power poles.

Birder Elaine Morrall has kept track of osprey nests in northern Arizona for twenty-five years. She says the adult birds are always back by April 1. Though ospreys do pair for life, it’s their fidelity to the same nest sites each year that impresses her. One nest by Lake Mary near Flagstaff has been active since the 1970s.

The female bird lays two or three eggs, and will incubate them for about a month. By July the eggs have hatched. Then it’s mom who mostly stays with the young, while dad brings home fresh fish to the noisy brood.

It’s mesmerizing to watch osprey fish. They fly in over the water, see their prey, then swoop down and snatch a fish in their sharp, curved talons. With reversible outer toes and spiny footpads, they’re perfectly built to forage on the wing—and entertain us for hours beside a lake on a summer morning.