72 Microseasons of the Pacific Northwest

Ospreys (Pandion haliaetus) are among the most charismatic harbingers of spring in the Pacific Northwest. Returning from wintering grounds in Central and South America, they appear over Puget Sound lakes, the Columbia River, the Willamette Valley, and Interior Valley reservoirs in early April, immediately staking claim to the towering platform nests they used the previous year. Both birds in a pair typically return within days of each other, and the male can be seen ferrying sticks and fresh nesting material while the female calls from the nest rim. The birds are superbly visible. Unlike many raptors, osprey hunt in broad daylight over open water, hovering 30–100 feet above the surface, then plunging feet-first with a spectacular splash to seize fish — almost always oriented headfirst in the talons for aerodynamic carry. They bring their catch to a prominent perch or the nest edge, eating while the catch flaps. Common prey at this time of year includes trout, bass, and pikeminnow in lowland lakes and rivers. In the Puget Sound region, watch for nesting platforms at Jetty Island near Marysville and along the Snohomish River delta, where several nesting pairs have been monitored for years. The Willamette Valley supports a large breeding population, with pairs visible along the Willamette and McKenzie rivers and at Fern Ridge Reservoir near Eugene. Urban observers can find osprey over Lake Washington, Lake Union, and several Seattle-area parks beginning in mid-April. On the Cascade Loop, utility poles fitted with nesting platforms around Lake Chelan and the Methow Valley host easily watched pairs.