The Last Peregrine
Why surveys matter
“Half fearful of what I knew I would not find, I raced up the hill, scrambled over the broken talus beneath the cliff and climbed up onto the ledge. Except for a shallow scrape through the moss in one corner and the remnants of a few feathers, it was empty and lifeless. It was then it all hit home to me, of man’s ignorance, of his foolishness, and of his state of apathy to the state of the world around him and what he was doing to it.”
Keith Hodson wrote these words in 1970 at the age of 19, after finding yet another empty peregrine falcon nest. This nest was particularly meaningful to him – it was the first peregrine eyrie he’d ever visited back in 1966. Then, it had contained young falcons. Hodson was a summer student with Canadian Wildlife Service (CWS) biologist Richard Fyfe, one of the people racing against the clock trying to save the peregrine falcon from extinction.
Fyfe shared Hodson’s despair and frustration. In the early 1970s, Fyfe and his technician, Harry Armbruster, spent the last half of April and early May each year watching a very special pair of birds.
The male of the pair was a spectacular specimen, easily recognised by his jet black head and wildly pugnacious disposition. Nicknamed "Stud," this bird singlehandedly drove pairs of prairie falcons off their eggs, dispossessing them of nesting cliffs. His hunting forays were legendary – Stud handily took anything from migratory songbirds to local waterfowl. He was paired with several different females during the early 1970s and, as a talented hunter, helped produce several broods of young.
But in 1973, Stud returned to his cliff alone.
Just west of the tiny prairie town of Bow City, Fyfe and Armbruster took detailed notes on the breeding behaviour of the last pair of peregrine falcons reproducing south of the boreal forest and east of the Rocky Mountains in Canada. Several hundred pairs within this range had already died out in the 1950s and 1960s – a direct result of post-World War II use of the pesticide, DDT. The men watched the birds hunt, recorded details of their courtship, and monitored their breeding success. They knew they might well be among the last humans to enjoy such an experience.
Although Stud courted female peregrine falcons flying by (probably migrants headed north), he could not entice them to stay. He held the territory for the spring of 1973, and the next one, and the one after that, but never again successfully wooed a female. Stud was seen for the last time on May 29, 1975. An Edmonton Journal article reported the demise of the Bow City pair in an article titled, “Rare Falcon Missing: Extinction Feared.” Technically, with the loss of Stud, peregrines had been extirpated in Canada, east of the Rockies and south of the boreal forest, but for biologists and others who passionately cared about raptors, the fear of eventual extinction was real.
At the time, Canada had already banned the use of DDT. The United States was about to follow. Unfortunately, populations of species like the peregrine, bald eagle, and osprey had already been decimated. In the United States, not a single peregrine falcon pair could be found breeding east of the Mississippi River and the bald eagle was all but gone from the lower 48 states. In other parts of the world, bird- and fish-eating raptors had suffered a similar fate. Despite bans on using DDT in the western nations, the outlook was still bleak. With typical first world hypocrisy, the manufacture of DDT and other harmful organochlorine pesticides had been exported to the third world. These compounds would be used in developing nations by the mega-ton for decades. Global levels of DDT did not start dropping until the late 1980s, when better pest management regimes, informed concern, and DDT-resistant pest species saw fewer people using it.
Back in 1973, Fyfe and Armbruster had no idea what lay ahead in terms of global DDT residue trends, but they certainly knew the compound’s effects on Canada’s raptors. It must have been with heavy hearts they witnessed the saga of Stud and that of countless other peregrine pairs along the river systems in western Canada. They eventually documented the extirpation of the peregrine along the Bow, Milk, Oldman, South Saskatchewan, North Saskatchewan, Pembina, McLeod, and Athabasca rivers in Alberta.
A nation-wide survey in 1970 established the severity of the peregrine decline. At a federal provincial wildlife conference in the same year, it became clear that emergency measures were required. And so CWS, along with provincial wildlife agencies and private falconers, began consolidating a captive population of peregrine falcons to archive the remaining genetic resources in a controlled environment. Theoretically, the captive population would be maintained until the world was clean enough to support reintroduction. This was a remarkably ambitious undertaking – only a handful of peregrines had been bred in captivity to that point.
In the early 1970s, young birds were taken from the few remaining nests in western Canada, including offspring produced by Stud and his mates. Additional birds were donated to the program by falconers who recognized captive breeding as a last resort. Through the dedicated labour of people like CWS falcon technician, Phil Trefry, the crew at the peregrine breeding facility (located on CFB Wainwright) achieved the unthinkable. They produced their first baby peregrines as early as 1975. As Albertans, we can be proud knowing that many of the techniques for producing endangered raptors in captive settings were pioneered right here in our province. Young birds produced by the Wainwright “flock,” and a few smaller sister breeding programs elsewhere in the country, were available for experimental reintroduction as early as 1976. Large-scale reintroductions followed for the next two decades. With DDT residue levels declining globally, the scene was set for a remarkable population recovery.
Since 1970, national peregrine falcon surveys have been done every five years in Canada. The goal each time is to check all historically occupied nest sites for peregrines, giving us a good handle on the speed and magnitude of peregrine recovery. In the last 15 years, surveys across the country have documented a strong recovery, driven mainly by the reintroduction of captive-bred peregrines. Happily, about two-thirds of the peregrine population has returned to natural, historically occupied nest sites in Alberta. What’s more, these surveys have documented peregrines at many new sites, including a substantial number of pairs nesting on man-made structures. Over 70 cities in North America these days boast at least one pair of nesting peregrines. In Edmonton, we have had as many as eight pairs, in Calgary three, and in Red Deer two.
Surveys for peregrines are expensive. But monitoring populations of species at risk is extremely important. It’s the only way to evaluate if management programs are effective and when a species can be considered recovered.
A recovered species?
Last summer, surveyors checked 158 of 172 historically occupied nest sites in Alberta, and followed up many reports of pairs possibly nesting at previously undocumented locations. By late August, crews had found 68 occupied peregrine territories, up from only three (with only one productive) in 1970. Almost two-thirds of these were at natural nest cliffs, most in northern Alberta. The recovery in Wood Buffalo National Park (WBNP) and the Canadian Shield eco-zone north of Lake Athabasca has been particularly impressive.
I was lucky enough to accompany CWS biologist Geoff Holroyd and park ecologists Rhona Kindopp and Mike Vassal on the survey of the northern population. I first worked with peregrines in that part of the world in 1977. Back then peregrines in the region occupied only five territories; last summer we found 40! There exists a 30 kilometre section of the Peace River in WBNP where good peregrine cliffs abound. In 1977, the area hosted a single pair of peregrines. This year we found no fewer than eight pairs! Choppering our way back to the Fort Smith airport at the survey’s end, I thought about the many biologists who worked on peregrines in northern Alberta over the years, including some of Alberta’s first female field biologists like Lizzane Johnstone-Beaver and Ursula Banasch. They would all be delighted with the recovery news and likely a bit proud!
At 68 occupied territories, the peregrine falcon is well on its way to recovery in Alberta. In fact, the primary goal for the Alberta Peregrine Falcon Recovery Plan (approved in 2004 by the Minister of Sustainable Resource Development) was to achieve 70 pairs by 2010. Pairs have been re-established at other natural cliffs on the North Saskatchewan and Red Deer Rivers, and we hope these populations will expand in the coming years. With luck they may well repopulate other drainages in the historical range. Presently there exists interest in bolstering such recovery by releasing captive-raised young in the area.
So…the peregrine is back. Impressively, a study of the lineage of Alberta’s wild peregrine falcons shows that approximately 95 percent of the genetic diversity once archived at CWS Wainwright now exists in the wild population. Stud may have been considered the last peregrine by some, but – happily – that condition was temporary. His descendents are alive and well and flying in Alberta today.
Dr. Gordon Court is a frequent contributor to Conservation Magazine. He has studied the breeding biology and toxicology of predatory birds at both ends of the earth. His Ph.D involved the study of marine pollutants in sea birds breeding on Ross Island, Antarctica. Earlier in his career, he completed a Master of Science degree on the toxicology and breeding biology of Tundra Peregrine Falcons in the Canadian Arctic. This study continues today and is one of the most intensive research projects ever undertaken on the peregrine falcon.
Gordon has also worked for over three decades on the recovery of the peregrine falcon in western Canada and is reconized internationally as an expert on this species. Gordon is formerly the Canadian Director of the U.S.-based Raptor Research Foundation. Presently, he is the Provincial Wildlife Status Biologist for Alberta Sustainable Resource Development.