(Posted July 14, 2003)

HUNTINGDON, Pa. -- The osprey, a fish-eating bird of prey related to eagles and hawks, may once again permanently soar over the fish-rich waters of Raystown Lake if a new introduction program created by Juniata College and the Army Corps of Engineers takes wing.

?Populations of osprey declined perilously in the 1960s because of pesticide pollution,? explains Chuck Yohn, director of the Juniata College Raystown Field Station. ?The population of osprey has since rebounded, but there are no breeding populations in the Susquehanna River basin north of Harrisburg.?

Yohn adds that osprey imprint on the area in which they are hatched and mature to the point of flight. ?They return to area where they were fledged in order to breed,? he says. Ospreys have not historically nested and bred in central Pennsylvania because Raystown Lake existed in a much smaller size prior to the mid-1970s Army Corps of Engineers project that expanded the lake to its present size.

To introduce breeding pairs of osprey to the area, Juniata and Jeff Krause, wildlife biologist and resource manager for the Army Corps of Engineers, have collaborated on a breeding project that will raise and release six young osprey this summer. Over the next three years a total of 18 osprey fledglings will be released at a site near Juniata?s boat harbor.

Raystown Lake is an ideal breeding site for ospreys, primarily because it has a vast area of open water and a high population of forage fish. Ospreys, which are slightly smaller than eagles, sporting a four- to five-foot wingspan, feed only on fish. In addition, ospreys can periodically be seen in the Raystown area during migration season, but no opsrey nesting site has ever been reported in the area, according to Yohn.

Ospreys, which are still listed as a threatened species by the U.S. Fish and Wildlife Service, also are very tolerant of human activity in their nesting habitat, seemingly unbothered by boat noise, loud voices or other activity.

The first six birds were obtained from a wildlife biologist in Pomonkey, Md. and carefully transported to the Juniata field station. Juniata and the Corps of Engineers have constructed a 25-foot hacking tower where the six fledglings are raised until they are ready to hunt on their own. The six ospreys should be at or near the site until mid-August. As of Monday, July 14, three ospreys are flying near the hacking tower and three have still not emerged from the hacking tower.

The birds were at least four weeks old upon arrival at Juniata. The birds have been monitored by three Juniata students, Hillary Bright, a research assistant and 2003 graduate from Spruce Creek, Pa., Tanya Dierolf, a senior from Barto, Pa., and Matt Sauers, a junior from Evans City, Pa.

?We feed them through a one-way mirror in the hacking tower using fish impaled on a stick,? Bright explains, noting that the researchers want to avoid human contact with the birds. ?They eat carp, trout, rock bass and perch.?

Once the ospreys are mature enough to leave the site, they will fly away on migratory routes, but will not return to Raystown for three years. ?Essentially the ospreys need three years to mature and they ?wander? for those years and return to their original nesting site when it comes time to breed.?

All six ospreys have been banded with color-coded bands used by the national Fish and Wildlife Service. When ospreys return to Raystown Lake to breed, Juniata scientists will observe nesting sites to determine if the nesting pairs are banded.

Other collaborators on this project are Americorps, Pennsylvania Conservation Corps, the Pennsylvania Game Commission, Penn State University and KL Mills Inc.


Contact April Feagley at feaglea@juniata.edu or (814) 641-3131 for more information.