Peregrine falcons made news recently, in a story about their amazing return from the brink of extinction, and the role that Minnesotans have played in their recovery. It’s a story every bit as dramatic as the return to abundance of the wood duck, a staple species in the bags of Minnesota duck hunters, a bird whose survival in the late 19th and early 20th century was threatened by market shooting for its plumage and flesh, and loss of its habitat.
Peregrine falcons were virtually eliminated from North America by the mid-20th century, with just a few nesting pairs remaining, mostly in the west. This was due almost entirely to the use of agricultural chemicals like DDT, which accumulated in the birds as they ate DDT-laced prey, causing peregrine egg shells to become brittle and break. This was true of bald eagles at the time, as well.
Banning DDT eventually eliminated the nesting failures caused by fragile eggs. But the peregrine’s preferred elevated nesting sites, primarily cliffs, were diminishing in number and value with human development, and with expanding numbers of raccoons, that great nest robber that seems to become more abundant in the shadow of man.
The peregrine, never extremely abundant due to its territorial nature and specialized nesting preferences, was restored to Minnesota skies by a group of ornithologists who were visionary enough to imagine that it could adapt to an urban environment, something few laymen would have expected from this top-of-the-food chain raptor.
Harrison B. “Bud” Tordoff was one of those who thought that the peregrine might be able to adapt to a new environment, and new prey. Peregrines hunt by “stooping,” or diving from above. When stooping on their prey from great heights they can approach or exceed 200 miles per hour, striking and stunning, or killing their prey outright.
Release of captured and relocated birds in the 1980s worked because the peregrine adapted to nesting on tall man-made structures, like skyscrapers and smoke stacks, and feeding on an abundant food source present in almost all man-dominated urban environments, the lowly rock, or common pigeon.
This has worked so well that today you can even watch peregrines raising their young in a nest box on a power plant smoke stack several hundred feet above the ground, via webcams that have been installed at three Xcel Energy power generating facilities. This nest box installation practice has become a model procedure at numerous power plants in the U.S., and even abroad.
Tordoff was a distinguished ornithologist, teaching at the University of Minnesota, and serving as director of its James Ford Bell Museum of Natural History, a place I spent many a lunch break while a student there, captivated by its extremely realistic dioramas of wildlife and habitats from all across Minnesota. He also served as interim head of the University’s School of Agriculture, which included forestry, wildlife management and horticulture, as well as the expected cows and crops!
Bud Tordoff was a classic example of a person who is both a hunter and a lover and protector of wildlife. His way of life was a demonstration of the belief that man is a part of nature, a predator in his own right, but capable of the special trait of concern for the welfare of species other than his own.
Like the wood duck that was saved from becoming a marginal, rare species, the future for the peregrine falcon looks very bright, too. There are now believed to be 2,000 to 3,000 nesting pairs in North America, occupying both wild and urban environments.
In Minnesota, there are peregrines returning from wintering grounds in Central and South America to raise their young on the scenic cliffs of the North Shore of Lake Superior and along the Mississippi River, as well as on tall downtown buildings and smoke stacks in Minneapolis and St. Paul. The peregrine falcon is no longer considered an endangered species.
Take a bow, Bud and friends.