Osprey (Pandion haliaetus)

Pennsylvania Threatened State Rank: S2B (imperiled, breeding) Global Rank: G3 (vulneralbe)

What it looks like: The osprey, or fish eagle, is a distinctive bird of prey with white underparts, a brown back and wings, and a white head with a small crest and a brown eye stripe. A “necklace” of dark streaks is more common on the females than the males. Fish make up the vast majority of the osprey’s diet.

Where it is found: Ospreys inhabit every continent but Antarctica, nesting in trees, snags, and man­made structures located near high quality David Behrans, Animal Diversity Web fresh­ or saltwater fishing grounds.

Why it is rare: Like the bald eagle, the osprey suffered declines linked to the use of a group of chemicals called organochlorines in the mid­ twentieth century. These toxins bioaccumulate or become more concentrated as they moved up the food chain from aquatic organisms to fish, until top predators like ospreys received the chemical in much higher concentrations than were present in their immediate environment. This resulted in birds laying thin­shelled eggs that endangered the developing young. Osprey populations have begun to recover as organochlorine Npeortstich ideA museer deicaclin Snes tainte the/P rovUniitnced eS Constates. ervation Status Map by NatureServe (August 2007) Conservation considerations: Osprey populations can be supported by the construction of nesting platforms, protection of breeding and fishing habitat, and releasing captive­raised fledglings. Continued reduction and monitoring of pollutants including pesticides and heavy metals will also be necessary, since top State/Province predators such as the osprey are Status Ranks particularly vulnerable to these poisons. SX – presumed extirpated Reduction of organochlorine pesticide use SH – possibly extirpated S1 – critically imperiled in the species’ South American range is a S2 – imperiled high priority. S3 – vulnerable S4 – apparently secure S5 – secure Not ranked/under review

Saving the places

References • Brauning, Daniel W., ed. 1992. Atlas of Breeding Birds in Pennsylvania. Pittsburgh: University of Pittsburgh Press. 90­1. • Henny, Charles J.; James L. Kaiser; Robert A. Grove; V. Raymond Bentley; John E. Elliott. 2003. Biomagnification Factors (Fish to Osprey Eggs from Willamette River, Oregon, U.S.A.) for PCDDs, PCDFs, PCBs and OC Pesticides. Environmental Monitoring and Assessment, 84(3): 275 – 315. • Kirschbaum, K. 2000. "Pandion haliaetus.” Animal Diversity Web [web application]. University of Michigan Museum of Zoology, Ann Arbor, Michigan. Available at http://animaldiversity.ummz.umich.edu/site/accounts/ information/Pandion_haliaetus.html. Accessed 24 February 2005. • NatureServe. 2007. NatureServe Explorer: An online encyclopedia of life [web application]. Version 6.2. NatureServe, Arlington, Virginia. Available at http://www.natureserve.org/explorer. Accessed 13 August 2007.