We’ve had a number of wildlife success stories over the past 20 to 30 years. The number of Bald Eagles, Osprey and Trumpeter swans, for example, were nearly wiped out but now have returned. I can remember very well a time when there were very few Bald Eagles and no Osprey and Trumpeters at all. I remember very well when these species were reintroduced in locations all across the Midwest. These birds are now common in many regions.
However, no species has recovered with as much amazing success as the Peregrine Falcon (Falco peregrinus). The peregrine was wiped out in the East and Midwest by the late 1950s and early ’60s due to DDT poisoning and illegal shooting. No longer did this magnificent falcon patrol the skies in search of an avian diner.
In the Midwest there was never a large or robust population. It was estimated that only about 40 pairs (total of 80 adult birds) were living mainly on rocky cliff faces in the early 1900s before World War II and the precipitous decline of this species.
The recovery work on the Peregrine Falcon began in the early 1980s, when a number of captive bred youngsters were released into the wild at strategic locations around the Midwest. In the ensuing decades, over 1,200 young peregrines were released into the wild at locations across 13 states and two Canadian provinces.
Today, the number of wild Peregrines is astounding. Each year over 500 young Peregrine Falcons are born to wild parents in the Midwest alone. These young are coming from over 100 nesting pairs. Captive breed release is no longer necessary since the young are now wild born.
Why such success
Remember, historically there were only about 40 pairs in the Midwest prior to being wiped out. Clearly, the reintroduction effort has overshot the original number of birds. But why? How? Well, to see why these masters of the sky are so successful you need to look no further than your local big city. All of the original falcons nested on natural rock cliff faces. Today, 52 percent of all the nests are on tall buildings. Another 8 percent are on bridges, 14 percent on smokestacks and only 26 percent are on cliff faces. So that means 75 percent of the Peregrines these days are nesting on non-cliff structures.
The current population of Peregrines is four to five times greater than the historical population. In addition, over 500 young peregrines are fledglings each year throughout the Midwest, producing a large population of non-breeding birds who are living in cities taking advantage of the pigeons.
It appears that the population growth is leveling off due to the saturation of the habitats, mainly tall city buildings. So I would say that by any measure, the comeback of the Peregrine Falcon has been nothing short of amazing and hugely successful. Perhaps we need more wildlife success stories like this one. Until next time …
Stan Tekiela, Victoria, is an author-naturalist and wildlife photographer. He travels the U.S. to study and photograph wildlife. You can follow him on twitter.com and facebook.com or visit his web page at www.naturesmart.com. His column appears regularly in the Advocate.