Ospreys live near water, such as rivers, lakes and the coast. They eat almost nothing but fish, and the osprey typically feeds on fish 4 to 12 inches long. As of November 2026, studies in North America have documented more than 80 different prey species of ospreys. An osprey flies over the water and hovers, and then it plunges toward the water to catch a fish, and National Geographic says ospreys hunt by diving to the water's surface from some 30 to 100 feet up. Ospreys have been known to dive up to one metre below the surface of the water to catch prey. An osprey uses strong, almost horizontal wing beats to lift itself and its prey from the water. Ospreys hunt for fish from the air, flying up to about 40 meters above the water.
An osprey watches for movement just beneath the surface of the water. Ospreys have four types of colour receptors in the eye, while people have three. An osprey's eyes also have a very high density of receptors, which gives it much better visual acuity than people have; ospreys catch fish on about a quarter or more of their dives. How often an osprey catches a fish depends on its own ability, the weather and the tide. Some studies have shown that ospreys are most successful at hunting at midtide and when the weather is calm. Breeding ospreys are known to travel as far as 14 km from their nest during hunting forays.
An osprey has rough pads on its feet that help it hold a slippery fish; the underside of its feet has rough, spiny pads called spicules, and an outer toe on each foot can swing around to join the rear toe. Ospreys have relatively long legs for a raptor. An osprey has a see-through third eyelid that it closes when it dives into the water. Ospreys have dense oily plumage and efficient nasal valves that prevent water from entering the nostrils. The pale underside of an osprey's plumage can help it blend into the bright sky. Ospreys do not generally need to drink water, because fish flesh supplies enough water to meet their needs.
Widespread use of the pesticide DDT caused osprey numbers to fall in the mid-1900s. Osprey numbers in North America largely rebounded after DDT was banned. The osprey population in the Chesapeake Bay fell to a low of about 1,450 pairs in the early 1970s, and by the mid-1990s there were about 3,500 pairs of breeding ospreys in the Chesapeake Bay area. As of November 2026, the Chesapeake Bay Program places the Chesapeake Bay's current osprey population at eight to 10,000 breeding pairs. As of November 2026, regions where ospreys are particularly abundant include Scandinavia and the Chesapeake Bay region of the United States.
Ospreys build large, bulky nests of sticks and branches, on telephone poles, channel markers and other structures. They choose nest structures that can support a bulky nest and that are safe from ground-based predators. Osprey pairs use the same nest year after year, and they add new material each year, so the nest can become huge. A female osprey lays two to four eggs over several days, each one 1 to 2 days after the one before. Osprey incubation starts when the first egg is laid, so the eggs hatch in the order in which they were laid. The eggs hatch after about 40 days of incubation. Young ospreys take their first flight at about 50 to 55 days old. Ospreys are sexually mature at about 3 years old, but may not breed until age 5 where nest sites are scarce.
Most ospreys breed in the north and migrate south for the winter, and they migrate alone, not in flocks. Ospreys heading south from the Midwest and East Coast populations average about 130 miles a day. The yearly migration of UK ospreys is a round trip of some 12,000 km. Ospreys arrive in the Chesapeake Bay region in early March and stay through spring and summer. On a normal migration day, an osprey's ground speed is between 20 and 30 miles per hour. Ospreys can regularly cover over 100 km a day on migration, or even fly non-stop for 48 hours. The osprey subspecies Pandion haliaetus carolinensis breeds in North America and the Caribbean and winters in South America.
