Celebrating The Peregrines Return To Iowa

February 19, 2009 by · 3 Comments 

“It’s been an incredible year for peregrine falcons. We now have more peregrines nesting back on natural cliffs than we do on buildings.” Bob Anderson, Director, Raptor Resource Project

WAUKON JUNCTION IOWA – Assembled along the stone base of a towering Mississippi river cliff, a hopeful collection of falconers peer skyward. Traveling from across four Midwestern states, the congregation of raptor enthusiasts arrived in Allamakee County late last summer, all hoping to catch a glimpse of the elusive peregrine falcon alive and wild in its native habitat.

Although once listed as a common inhabitant of the Mississippi river blufflands, uninhibited post World War II use of DDT pesticides had a devastating effect peregrine populations. By the late 1960s, DDT contamination had completely eradicated the species in Iowa as well as from the entire eastern half of the U.S.

But times are changing. Thanks to an aggressive conservation effort spearheaded by Iowa falconers, this dynamic species is currently staging a dramatic comeback.

For those possessing patience and a good pair of binoculars, the chance of seeing a modern-day, free flying peregrine is all but assured. For last summer’s peregrine watchers, the wait was amazingly short. The first falcon was spotted within six minutes.

“Here comes one now,” announced Raptor Resource Project Director and Iowa falconer, Bob Anderson. Based at Decorah, Anderson’s Raptor Project has long aided in the peregrine’s recovery and is currently monitoring the bird’s return to historic Mississippi river nest sites.

As if on cue, the speeding falcon turned and then passed directly above the earthbound onlookers. Raising his binoculars, Anderson quickly confirmed that the bird was a young-of-the-year male, one of three youngsters produced at the Waukon Junction cliff this summer.

“This has really been a remarkable year for peregrines,” said Anderson. “So far, we’ve documented peregrine activity on 23 separate Mississippi river cliffs which is a gain of 5 new territories over last year.”

“It really is amazing. Less than ten years ago, there were no peregrine falcons nesting on natural cliff sites, but all that has changed,” said Anderson. “Today, the cliff birds outnumber the ‘city falcons’ that nest on skyscrapers and other [urban] structures. The ultimate goal of this recovery has been to return falcons to historic cliff sites, and now they’ve accomplished that.”

But although there is ample cause for celebration, Anderson cautions that modern-day peregrines are not necessarily home free.

Midwestern peregrines have been the most studied bird population in the U.S., notes Anderson. Falcons nesting on natural cliff ledges are exposed to ‘real world’ hazards. By analyzing data obtained from ongoing leg band readings, Raptor Resource Project observers are discovering that Mississippi river peregrine populations have a much faster turnover than their longer lived urban counterparts.

“When first attempting the river recovery, we assumed that great horned owls would pose one of the greatest threats to peregrine survival,” says Anderson. “We were wrong. Instead we’ve discovered that peregrines are more than capable of dealing with the danger of horned owls. Adult peregrines will also show aggression toward birds like red-tailed hawks and bald eagles, and will drive them away from nest sites. But show peregrines a horned owl, and the aggression becomes intense. They just turn into Tasmanian devils, and owls don‘t stand a chance of taking their youngsters. Right now, rain and raccoons seem to be the limiting factor on peregrine eggs and young.”

Included among last year’s crowd of Hawk Heads was Ross Dirks, master falconer and owner of Northwest Iowa’s Dickinson County Animal Clinic. A charter member of the Iowa Peregrine Falcon Recovery Team, Dirks actively sponsored the release of young peregrines to Mississippi river blufflands.

“This is just an incredible event,” said Dirks. “Now I can say that I’ve actually been to the Mississippi river and have seen wild peregrines nesting on a natural cliff in Iowa.”

“When the river recovery work began, we all knew that there would be risks and no one knew for sure if this could work. But now, the peregrine falcon has returned.”

“To have this species back on historic cliffs in Iowa is just an amazing accomplishment,” Dirks added. “It’s simply amazing.”

A peregrine falcon chick surveys its surroundings from atop a Mississippi river cliff ledge. As a direct result of efforts of the Iowa Peregrine Falcon Recovery Team, wild peregrines are currently returning to recolonize historic eyries up and down the upper Mississippi.

During 2008, expanding falcon populations established a new modern-day record. The falcons’ successful restoration to natural cliff sites is the direct result of efforts of the Iowa Peregrine Falcon Recovery Team. Comprised largely of Iowa falconers, the group’s raised more than $100 thousand from 1998 to 2000. The funds were used to construct and maintain hack sites and for the purchase and release 117 captive reared, young peregrines.

Article and photos by: Lowell Washburn