Osprey Fact Sheet
New York Status: Special Concern
Federal Status: Not Listed
The osprey is a large bird of prey measuring 22-25 inches (56-64 cm) with a wingspan of 4-6 feet (1.2-1.8 m). The sexes are nearly alike in plumage, but the female is slightly larger than the male. Adult plumage is dark brown above and white below. The white head has a dark crown with a characteristic dark brown streak on each side. Juvenile plumage resembles that of the adult, with buff to white tips on the feathers of the back and upper wing. In flight, the osprey's long, narrow wings appear to have a crook at the wrist where dark patches are also apparent.
Ospreys feed primarily on live fish, which they catch by using their long, hooked talons. An osprey sometimes plunges deep enough to momentarily submerge its entire body. The female lays one to four, but usually three, eggs in the spring in a large nest of sticks constructed at the top of a dead tree. Nesting platforms and other man-made structures are also commonly used. They also occasionally nest on the ground. The nest is often used year after year and can become quite large (up to 10 feet high!) as more material is added prior to each nesting season. The young fledge at about eight weeks of age, then remain in the area of the nest for about two months.
Distribution and Habitat
Ospreys breed on every continent except Antarctica. Only one of the five subspecies, Pandion haliaetus, occurs in North America. Here, its breeding range extends from northwestern Alaska across Canada south to Baja California in the west and to the Gulf States in the east.
In New York, there are two main breeding populations, one on Long Island and the other in the Adirondack Mountains. Within its range, the osprey prefers to make its home along the coastline, and on lakes and rivers.
The decline of this species was caused by DDT-induced eggshell thinning, which reduced the reproductive output of breeding pairs. In turn, the breeding population declined from an estimated 1,000 active nests in the 1940's between New York City and Boston, to an estimated 150 nests in 1969. Since the ban of the insecticide DDT in New York in 1971, and in the rest of the country in 1972, the population has slowly been making a comeback. In 1995, there were 230 breeding pairs on Long Island alone. In 1983, the osprey was down graded to "Threatened" from its 1976 listing as "Endangered", and in 1999 it was down graded from "Threatened" to "Special Concern."
Management and Research Needs
The osprey is probably the longest studied and monitored raptor in New York. The New York State Department of Environmental Conservation (NYSDEC) monitors the status and productivity of the majority of New York's population. Each year, both ground and aerial surveys are conducted by NYSDEC to document osprey nests in the state.
From 1980-1987, the NYSDEC released 36 young ospreys taken from nests on Long Island in an attempt to establish a third or "satellite" population in southwestern New York. During the seven years of the project, 30 young ospreys were released into the wild. This has lead to successful nests in the area, including nine nesting pairs in 1998. There are also close to a dozen breeding pairs in central New York and one in Southeastern New York in Sullivan County.
Bull, J. 1974. Birds of New York State. Doubleday/Natural History Press. Pp.166- 172.
Carroll, J. R. 1988. Osprey, Pandion haliaetus. Pp. 98-99 in R. F. Andrle and J. R. Carroll, Eds.The Atlas of Breeding Birds in New York State. Cornell Univ. Press, Ithaca, NY. 551 pp.
Clum, N. 1986. The Effects of Prey Quantity on Reproductive Success of Osprey (P andion haliaetus) in the Adirondack Mountains. M. S. Thesis (unpubl.). Graduate School of Cornell University, Ithaca, NY. 149 pp.
Farrand, J. Jr.,ed. 1983. The Audubon Society Master Guide to Birding. Vol. 1:Loons to Sandpipers. Alfred A. Knopf, Inc., New York. Pp 216-217.
Levine, E., Ed. 1998. Bull's Birds of New York State. Cornell University Press, Ithaca, NY. pp. 178-180.
Poole, A. 1989. Ospreys: A Natural and Unnatural History. Cambridge Univ . Press, Great Britain.
Spitzer, P. 1979. Dynamics of a Discrete Coastal Breeding Population of Ospreys in the Northeastern U. S., 1969-1979. Ph.D. Thesis (unpublished). Graduate School of Cornell University, Ithaca, NY. 55 pp.
Terres, J. R. 1980. The Audubon Society Encyclopedia of North American Birds. Alfred A. Knopf, New York. Pp. 644-646.
Drawing by Karen L. Allaben-Confer
More about Osprey Fact Sheet:
- Osprey - Fascinating facts and information about the appearance,habitat preferences and best places to view ospreys.