The osprey, also known as the "Fish Hawk", is equipped with short, spiny projections, or spicules, on the soles of its feet. These spicules, along with sharp, curved talons and the ability to swivel one of its toes around for a better gripping angle, make the osprey well adapted to catching its favorite prey: the slippery fish of oceans, lakes and streams. The osprey will build its home near any one of these bodies of water, with little regard to the surrounding environment, as long as an abundant food source is available.

Osprey populations began declining in the late 1800s and early 1900s due to habitat loss, hunting and egg collecting. This decline was exacerbated by the introduction and extensive use of DDT, and later PCBs and dieldrin. Ospreys are considered a threatened or endangered species in many regions, but government bans on DDT and tightened controls on the use of pesticides are helping osprey populations to recover.

Physical Description:

Length:
53 - 61 cm (21 - 24 inches)

Physical characteristics:
Brown above and white below. Head is white with dark brown stripe through the eye and on the side of the face. Wings have dark brown wrists and secondaries. The female has a "necklace" of brown feathers across its breast while the male is all white below.

Voice:
Short, musical chirping: tewp, tewp, teelee, teelee, tewp.

Breeding habitat:
Lakes, rivers, and seacoasts.

Mating system:
Monogamous; one brood per season.

Nest:
Historically placed in a tall dead tree, or on a stump surrounded by water, the nest is a bulky affair built of sticks and debris, to which a mating pair will return year after year. Long-established nests may be several feet deep, with younger birds replacing members of the established pair as one of them dies. Ospreys and are also known to nest atop telephone poles, buoys, light poles, and even abandoned duck blinds, and sometimes nest in loose colonies.

Eggs:
2-4 white or buff eggs with brown spots.

Chick development:
Eggs are incubated for a period of 32-43 days, generally by the female, although the male may take over when the female leaves the nest to fish or exercise. When the chicks are hatched, it is the male who brings fish to the nest, after removing the head and entrails, but it is usually the female who feeds the nestlings directly. The young, who are altricial at hatching, fledge after a period of 48-59 days.

Diet:
Mostly fish, as well as some snakes and other reptiles.

Conservation:
Osprey populations saw their first major decline in the late 1800s, due to habitat loss, hunting, and egg collecting. Not much later, predator birds like the osprey were tragically affected by the use of DDT, which accumulates at each level of the food chain and contaminates top level predators with high dosages. DDT contamination inhibits calcium metabolism in birds, reducing the thickness of eggshells so drastically that the weight of a bird attempting to incubate her eggs will crush them instead. DDT contamination remains in the body for several years, and thus continued to affect breeding productivity even after DDT was banned in the United States.
Use of pesticides other than DDT, loss of habitat and shortages of prey continue to affect osprey populations, and they are still recognized as threatened or endangered species in many of the fifty states. However, stricter controls on pesticide use and the construction of man-made nesting towers seem to be helping the osprey population along the road to recovery.

Breeding:
In the western hemisphere, breeds from Alaska and Newfoundland south to Florida and the Gulf Coast. Also breeds in Eurasia, North Africa, the East Indies, and Australia.

Winter:
The Gulf Coast and California south to Argentina.

Our Region:
The osprey population appears to be increasing in the Southern Appalachians and the osprey does not have special protection in either Tennessee or North Carolina.

In Park:
The osprey is listed in the park checklist as an occasional migrant, but as their population continues to increase in the east and in the Southern Appalachians in particular, this bird is becoming more common in the park and may now or soon breed in the park around Fontana Lake. First arrivals show up around the last week in March (earliest record: March 22, 2000) and they have been seen in the park as late as November 13 (1991). Most sightings have been reported from April and the last two weeks of September. Reports have come from all of the larger rivers and reservoirs in the park, including the Little River, Abrams Creek, Deep Creek, Little Pigeon River, Fontana Lake, and Chilhowee Lake, as well as from promontories during fall migration, such as Purchase Knob and Look Rock.

References:

Bent, Arthur Cleveland. Life Histories of North American Birds of Prey, Part 1. Dover edition, 1961. Dover Publications, Inc., New York.

Bull, John and John Farrand, Jr. The Audubon Society Field Guide to North American Birds: Eastern Region. 1977. Alfred A. Knopf, New York.

Gough, G. A., Sauer, J. R., Iliff, M. Patuxent Bird Identification Infocenter. 1998. Version 97.1. Patuxent Wildlife Research Center, Laurel, MD. http://www.mbr-pwrc.usgs.gov/id/framlst/infocenter.html.

New Jersey 's Endangered and Threatened Wildlife: Osprey (Pandion haliaetus). 2004. New Jersey Division of Fish and Wildlife, Trenton, NJ.

Parnell, James F., Eloise F. Potter and Robert P. Teulings. Birds of the Carolinas. 1980. The University of North Carolina Press, Chapel Hill.

Sibley, D.A. The Sibley Guide to Birds. 2000. Alfred A. Knopf, New York.