Osprey Facts

The osprey (Pandion haliaetus) is a large raptor that feeds exclusively on live fish. Ospreys are dark brown on the back and white on the belly and chest. The head is mostly brown with a distinct, dark stripe across the eyes. Although closely related to hawks and eagles, they are unique among raptors—possessing owl-like feet and wings that bend in flight like a gull—and the sole member of the genus Pandion and family Pandionidae. Ospreys can be found on every continent except for Antarctica, and they look the same all over the world.

Chicks
Covered in down and weighing only two ounces when they hatch, osprey chicks will begin to grow feathers almost immediately, and will be ready to test their wings within 5 to 7 weeks. Chicks are hatched with brownish, reddish, or orange-tinted eyes, which change as they mature to a bright yellow color.

Adults
Ospreys grow to be about 2 feet long in adulthood, with a wingspan of 4.5 to 6 feet. Adults generally weigh 2.5 to 4 pounds, with females tending to be slightly larger than males. While they normally top out at around 30 – 40 miles per hour in flight, ospreys are capable of reaching 80 mph in steep dives while hunting fish.

Breeding Pairs
Breeding pairs of osprey usually form a life-long bond. Ospreys most often breed near freshwater lakes. Both the male and the female will tend to the eggs, although the female does most of the incubation. Once the eggs are laid, the female no longer hunts, and the male must supply all of the food.

Nests
Osprey nests are among the largest built by any bird. Measuring at least 3 feet deep and 5 feet across, osprey nests are built primarily of sticks, with softer materials like bark, moss, or grass lining the inside. Ospreys locate their nests high off the ground—in trees, rocky outcrops, or on utility poles. Usually, ospreys return to the same nests every year, building the structure up over time.

Hunting & Feeding
Ospreys are expert hunters, well-adapted to catching live fish. Locating their prey from the air, ospreys will sometimes dive more than 100 feet, pulling up at the last moment before plunging feet-first into the water to capture a fish. Sometimes going completely underwater, the osprey has unique nostrils that close to keep out water. Their heavily muscled legs, powerful wings, and strong feet allow them to catch and fly off with fish up to three feet below the surface of the water! As the osprey rises in flight, it will grasp the fish firmly with two claws facing forward and two facing back. Adult ospreys are capable of carrying fish that equal their own size.

Migration
Ospreys arrive in New Hampshire in April and stay for the summer and early fall. In September, they head south to spend the winter months in Central and South America. While migrating, ospreys will usually travel during the daytime, only occasionally traveling by night.