Osprey Portrait

Ospreys are often called "sea hawks." Is that where the Seattle Seahawks got there name? No one knows for sure. The name was chosen in 1975, when it was selected from 1,741 different names that were suggested by 20,365 entries. Did the person with the winning entry have the osprey in mind when he submitted the name?

The osprey (Pandion haliaetus)—also known as the sea hawk, fish eagle, river hawk or fish hawk—is a large raptor, reaching more than 24 inches in length with a wingspan of up to 71 inches. As its other names suggest, the osprey's diet consists almost exclusively of fish—up to 99% fish. It possesses specialized physical characteristics and exhibits unique behavior to assist in hunting and catching prey. As a result of these unique characteristics, it has been given its own taxonomic genus, Pandion, and family, Pandionidae. Pandion is from the mythical Greek king of Athens, Pandion, and grandfather of Theseus, who was transformed into an eagle. Haliaetus is derived from the Greek for "sea eagle." The name "osprey" made its first appearance around 1460, via the Medieval Latin phrase for "bird of prey" (avis prede). Some wordsmiths trace the name even further back, to the Latin for "bone-breaker"—ossifragus.

The osprey is unusual in that it is a single living species that occurs nearly worldwide and is the second most widely distributed raptor species, after the peregrine falcon. It tolerates a wide variety of habitats, nesting in any location near a body of water providing an adequate food supply. It is found in temperate and tropical regions of every continent, except Antarctica, although in South America it occurs only as a non-breeding migrant. In North America, the osprey breeds from Alaska and Newfoundland south to the Gulf Coast and Florida, wintering further south from the southern United States through to Argentina.

The typical lifespan of an osprey is 7–10 years, though rarely individuals can grow to as old as 20–25 years. The oldest known North American osprey was 25 years, 2 months old. In North America, great horned owls, golden eagles and bald eagles are the only major predators of ospreys, capable of taking both nestlings and adults. However, kleptoparasitism by bald eagles—where the larger raptor steals the osprey's catch, often by stealing it right out of the osprey's talons, or harassing the osprey until it drops its catch which the eagle snatches out of the air—is more common than predation. Raccoons can be a serious threat to nestlings or eggs if they can access the nest.


How do ospreys live? Read on. 

Osprey Fishing




Ospreys are excellent anglers. They search for fish by flying on steady wingbeats and bowed wings, or circling high in the sky over relatively shallow water. Ospreys have vision that is well-adapted to detecting underwater objects from the air. Prey is first sighted when the osprey is 30–130 feet above the water, then they often hover briefly before diving, feet first, to grab a fish. You can often clearly see an osprey's catch in its talons as the bird carries it back to a nest or perch. When flying with prey, an osprey lines up its catch head first for less wind resistance.

Over several studies, ospreys caught fish on at least 1 in every 4 dives, with success rates sometimes as high as 70 percent. The average time they spent hunting before making a catch was about 12 minutes. An osprey typically takes fish weighing less than 11 ounces and 14 inches in length, but they can grab fish weighing up to 4.5 pounds. Ospreys are particularly well-adapted to this diet, with reversible outer toes, sharp spicules on the underside of the toes, nostrils that close to keep out water during dives, and backwards-facing scales on the talons which act as barbs to help hold their catch.

Occasionally, ospreys may prey on rodents, rabbits, hares, amphibians, other birds and small reptiles.




American and Canadian ospreys winter in South America, although some stay in the southernmost U.S. states, such as Florida and California. Some ospreys from Florida migrate to South America.

Although migrating predominantly in the day, they sometimes fly in the dark hours, particularly in crossings over water, and cover on average 160–170 miles per day with a maximum of about 270 miles per day. An osprey may log more than 160,000 migration miles during its 15-to-20-year lifetime. During 13 days in 2008, one osprey flew 2,700 miles—from Martha's Vineyard, Massachusetts, to French Guiana, South America.


How do we get more ospreys? Onward. 


Much of this text was borrowed from Cornell University's "All About Birds" and WikiPedia, fact-checked, and modified for McNary NWR. 

Osprey Nest




Osprey breed near freshwater lakes and rivers and sometimes on coastal brackish waters. Many nesting sites are used year after year, and some have been used for 70 years. The nest is a large heap of sticks, driftwood and seaweed built in forks of trees, rocky outcrops, utility poles, artificial platforms, or offshore islets. Buoys and navigational aids are a favorite site in the Columbia River.

Generally, ospreys reach sexual maturity and begin breeding around the age of three to four, though in some regions with high osprey densities, they may not start until five to seven years old. If there are no nesting sites available, young ospreys may be forced to delay breeding. To ease this problem, posts are sometimes erected to provide more sites suitable for nest building. In some areas nests are placed almost exclusively on artificial structures, like at McNary and elsewhere in the Mid-Columbia.

Ospreys usually mate for life. Rarely has polyandry been recorded. The breeding season varies according to latitude; on McNary they typically begin nesting in late March. The female lays two to four eggs within a month. The eggs are whitish with bold splotches of reddish-brown and are incubated for about 5 weeks prior to hatching.

Osprey eggs do not hatch all at once. Rather, the first chick emerges up to five days before the last one. The older hatchling dominates its younger siblings and can monopolize the food brought by the parents. If food is abundant, chicks share meals in relative harmony; in times of scarcity, younger ones may starve to death. The good news is that on McNary there is plenty of food, and the osprey nest has produced 2–4 fledglings every year the nest has been active. The newly hatched chicks weigh only about 2 ounces, but fledge in 8–10 weeks. It is fascinating to watch the young ospreys at McNary learn to fly; they begin flapping their wings, rising a few feet about the nesting platform, then settle back down to begin again.