Ospreys are large hawks with slender bodies, long narrow wings and long legs. Their posture when flying helps identify them – the kink in the wings makes an M-shape when seen from below.
They are brown above and white below and whiter than most raptors. When viewed from below, they are mostly white with a dark patch at the wrist. Their head is white and there is a brown stripe through the eye. They are big birds. From 21 to almost 23 inches long and with a wingspan of 59 to 71 inches, this is not your common backyard bird.
Ospreys are superb fishers and don’t eat much else. This diet keeps them close to ponds, rivers, lakes and coastal areas. They hunt by diving from 30 to 100 feet in the air down to the water’s surface plucking fish with curved claws and barred pads on their feet. And they are good at fishing! Studies have shown they make a successful catch 1 out of every 4 attempts and sometimes as high as 70%. After catching dinner, they will fly with the fish orienting the fish headfirst to ease wind resistance. Eagles and osprey, living in the same habitat, compete for food. Eagles will sometimes force the osprey to drop his fish which the eagle will catch in mid-air.
Ospreys are one of the most widespread birds of prey and live on every continent except Antarctica. Living 15 to 20 years in the wild, osprey may migrate more than 160,000 miles during its lifetime. Most ospreys that breed in North American fly to Central and South America for winter. The oldest known osprey was 25 years, 2 months old.
Ospreys usually lay three eggs which don’t hatch all at once. Hatching is staggered so the siblings are different ages; as many as five days between the oldest and youngest. If food is scarce, the older and more dominant birds will survive at the cost of the younger ones. Both parents incubate with the female staying with the hatchlings most of the time and the male bringing food for the whole family. It takes 51-54 days from hatch to first flight.
Our habitat is helping these birds. They like to build their stick and sod nests on telephone poles, duck blinds and similar structures. Efforts to preserve these birds include building nesting platforms. You can see a platform in use in Montana at this website: http://cams.allaboutbirds.org/channel/27/Hellgate_Ospreys/.
Ospreys have been endangered since the 1950’s due to DDT and other chemical pollutants but are making a comeback in many parts of North America.