Five Peregrine Falcons Successfully Released to the Wild at Ridgefield National Wildlife Refuge

Visitors to Ridgefield National Wildlife Refuge this summer may look up to see the spectacular sight of five juvenile Peregrine Falcons dog-fighting with one another as they practice improving their flying and hunting skills! The falcons' presence at Ridgefield is the result of an effort to protect the productivity of Oregon's bridge-nesting peregrines, led by the Audubon Society of Portland in cooperation with the US Fish and Wildlife Service-Ridgefield National Wildlife Refuge, Oregon Department of Transportation, Oregon Zoo, Oregon Department of Fish and Wildlife and Clark Public Utilities.

The five falcons released at Ridgefield all came from nests located on Oregon bridges. Although Peregrine Falcons typically nest on cliffs, they also substitute bridges and skyscrapers. Unfortunately, bridges present serious management challenges. Many of Oregon and Washington's bridges are in need of repair and are scheduled for construction during the next few years. While the goal is always to allow nesting peregrines to complete their nesting cycle without disturbance, Audubon Portland, Oregon Department of Fish and Wildlife and Oregon Department of Transportation recognized that there would be some construction projects where disturbance would be inevitable In 2001, a plan was developed to protect these peregrines and their offspring. Where nest failure appeared likely, eggs or nestlings would be removed from the bridge and raised in captivity. When they developed to the point of being able to fly, they would be released to the wild using a technique known as "hacking."

Three of the five birds released at Ridgefield were taken as eggs from the St. Johns Bridge on April 12th, 2003. just in advance of the major construction project that would have completely enveloped the nest location. The eggs were immediately transported to an incubator at the Oregon Zoo's Center for Species Survival. The eggs hatched on May 6th and 7th. At 10 days of age, the nestlings were transported to the Audubon Society of Portland where they continued to be cared for until June 14th, when they were placed in the hack box at Ridgefield. During their time in captivity, the young were fed either with a peregrine puppet or through a feeding chute to avoid imprinting them on humans.

Two additional birds, one from Portland's Fremont Bridge that was run over by a bicycle immediately after taking its first flight, and a second that fledged prematurely off the Astoria-Megler Bridge and could not be reunited with its parents, were later added to the group, bringing the total to five.

Hacking: At the age of 35 days, the peregrines were placed in a box atop a 30-foot tall tower that Ridgefield National Wildlife Refuge allowed us to construct on Bachelor Island.

Clark Public Utilities generously donated materials, time, personnel and equipment to build the tower. Audubon Portland volunteer Ken Barron constructed the hack box. Ken also donated more than a month of time to live out on the refuge and serve as hack site attendant (see related article next page). The objective was to have the falcons associate the tower with food so once released, they would continue to feed on food placed on the tower daily. Falcons instinctively begin to hunt, typically within a week of beginning to fly, but will not become proficient for several weeks. Providing food at the tower replicated the support that they would have received from their parents.

As of late July all five peregrines continued to be observed flying and hunting at Ridgefield. By early August the peregrines should be proficient hunters and feeding at the hack tower will be discontinued. Sometime during the winter the youngsters will likely disperse off the refuge for good. The hacking tower will be utilized when necessary in future years. While Bachelor Island - where the hack tower is located - is not open to the public, the young falcons have been frequently observed throughout open areas of the refuge.

Thanks to all of our partners in this project

Oregon Zoo, Oregon Department of Fish and Wildlife, Oregon Department of Transportation, Ridgefield National Wildlife Refuge, Clark Public Utilities, PGE, and Mason, Bruce and Gerard. Thanks in particular go to Ken Barron, Kelli Walker, Shawn St. Michael, Kelli Hoffman, Brook Beeler, Melinda Trask, Kendel Emerson, Holly Michael, Jennifer Brown, Eric Anderson, Joe Engler, Tom Murtaugh, Jim Wilmarth, Carole Hallet, Tracy Flemming, Cindy Humphreys, Marli Lintner, Jeff Wittler and the crew at Clark Public Utilities, Steve Hagen and the crew from PGE.