By Maggie Magliato, FOR Biology Intern
After spending 29 years on the Federal Endangered Species list, the “World’s Fastest Birds” have returned in adequate numbers across most of the United States. However, they are still listed as threatened in Virginia, and as of last year, there were 26 breeding pairs within state lines. According to Bryan Watts, director of the Center for Conservation Biology (CCB) in Williamsburg, there are two breeding pairs along the Rappahannock River, one on the Norris Bridge between Topping and White Stone near the mouth of the river, and another on the Downing Bridge at Tappahannock. The Norris Bridge pair lost the breeding male early this season, but a new male has been observed with the female.
At the Downing Bridge, three of the four eggs that were laid have hatched. The brood of three males was pulled from the nest box at four weeks of age on May 23 and transported to Shenandoah National Park to be hacked (a type of restoration process used with raptors). At Shenandoah National Park, falcons are brought to the hacking site when they are three-to-four weeks old. They are placed in a hack box, a protective box with a see-through screen so the birds can adjust and imprint on to their new location. The chicks are fed and cared for by park staff, while minimizing human contact. At six weeks old, the hack box door is opened for a “soft release.” For the next two-to-three weeks, the young falcons develop their flight skills. After about six weeks, when they’ve honed their hunting skills, they disperse. According to Rolf Gubler, biologist at Shenandoah National Park, this restoration work directly supports the conservation and long-term recovery efforts of statethreatened peregrine falcons in the park and throughout the Central Appalachians. As a result of the park’s ongoing restoration efforts, the park has supported a single nesting pair from 1994-1997, 2005-2007, and 2009-2014 (comprised of three different pairs). During this time, these “mountain” pairs have seen a 62% breeding success rate. This project has been a cooperative effort between the CCB, Shenandoah National Park, the Virginia Department of Game and Inland Fisheries and the Virginia Department of Transportation.
There are six peregrine falcon chicks currently being hacked at Shenandoah National Park, three of which are about to fledge, or leave the nest, and three that have just arrived from the Downing Bridge. “Hacking serves a dual purpose for these falcons, it increases the survival rate of fledglings at certain bridge nests/sites, and also aids in the recolonization of peregrines back into their historic range,” Gubler said, “The goal is to boost the population of the falcons in Virginia and the Central Appalachians, where there has been a lag in recovery. This has been a gradual restoration project that requires ongoing effort.”