If you ask a human what is the fastest animal on the planet, most will probably say it’s the cheetah. The correct answer is the peregrine falcon. When peregrine falcons tuck into their bullet-shaped stoop to attack prey from above they reach speeds exceeding 300 km/h. They are perfectly built for hunting at high speed. With brains that can process their vision at “frame rates” four times faster than humans and eyes that can see much more detail at distance, peregrines can clearly find and track their prey. During high-speed pursuits their baffled nostrils prevent rushing air from damaging their lungs. Nose cones on many modern jet engines mimic this clever adaptation. Despite all of these specializations, peregrines nearly went extinct a few decades ago.

A steep decline in raptor populations in the 1970s spurred a pulse in raptor research. Although peregrines are specialized predators at the top of their food chain, they are generalists when it comes to their choice of avian prey. Understanding this was a key factor in the story of their near extinction and the road to recovery. Years of research eventually determined that DDT, a toxic agricultural pesticide, was the primary cause for peregrine falcon population declines. DDT in the waterways was absorbed by macroinvertebrates and spread up the food chain in much higher concentrations through a process known as food web biomagnification. Researchers discovered toxic levels of DDT in many raptor species were causing eggs shells to become thinner. Eggs were breaking as parent birds tried to incubate them. Once this cause was recognized, a massive recovery effort was launched.

One Yukon biologist happened to be one of the main characters in this conservation success story. Dave Mossop knows that peregrines are the fastest animal on earth. He also knows that peregrines are a flagship species of the modern environmental movement. Dave is a well-known and respected bird biologist, naturalist, and professor; he is retired but still passionately continues his research and teaching. In 1976, Dave knew of only one breeding pair of peregrines left in the Yukon River population (one of five Yukon populations Dave monitored). Widespread banning of DDT, and a captive breeding and reintroduction program that Dave helped lead in the Yukon, enabled Yukon peregrine falcon populations to recover. Recent estimates from Dave’s surveys suggest that over 200 breeding pairs exist in the Yukon River population today, and they are no longer considered “at risk” by “species at risk” legislation. The peregrine recovery effort has been one of the most rewarding conservation stories Dave Mossop has been part of. There is still concern for long-term outcomes for peregrines because of climate change and other factors such as nest parasites and declining prey species. However, the peregrine story is an excellent example of what good research and dedicated people are doing to make a real difference in conservation.