| Endangered Species of Canada Stories by the Edmonton Journal, December 1999
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A GUIDE TO WILDLIFE AT RISK The Committee on the Status of Endangered Species, a federal advisory group, has created a list of 340 animals and plants that are in some jeopardy. Here are the categories the committee uses: Extinct — The species no longer exists in Canada Extirpated — A species no longer exists in the wild in Canada, but can be found elsewhere. Endangered — A species that faces imminent extirpation or extinction. Threatened — A species likely to become endangered if limiting factors are not reversed. Vulnerable — A species of special concern because of characteristics that make it particularly sensitive to human activities or natural events.
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The Edmonton Journal
November 25, 1999. Recovery efforts take wing Peregrine falcon’s status upgraded thanks to breeding programs, DDT ban
ED STRUZIK Journal Staff Writer RED DEER
PEREGRINE FALCON Falco peregrinus
For nearly two hours, we scoured the cliffside along the Red Deer River’s Valley of the Falcons hoping to find the peregrine falcon nest we knew was somewhere below. Even when biologists Gord Court and Steve Brechtel finally figured out where the screeching of hungry chicks was coming from, there was no way to get close enough to verify how many were in the nest of twigs. "These parents did a great job of picking out that site for a nest," said Court, the Alberta government biologist who has been co-ordinating peregrine recovery efforts across the province. "There’s no way a coyote or other predator could get at them up there. I don’t know that there’s any way we could get a peek unless we slung a rope down from the top." The fact there are any peregrines left in the Valley of the Falcons — or anywhere else in Canada, for that matter — is a testament to man’s ability to help an endangered species recover from the brink of extinction. Twenty seven years ago, all but one of the 70 to 90 breeding pairs that were nesting in the province disappeared. The decline, which reflected a worldwide pattern, had nothing to do with habitat loss, hunting or the many other factors that put birds and animals on the endangered species list. The culprit in this case was DDT, a pesticide noxious enough to kill any hawk, eagle or falcon that ingested enough of it. What really did in the peregrines was the long term buildup of the toxin in their systems. High levels of DDE, a metabolite of DDT, left the shells of their eggs so thin they broke before the chicks could hatch. With the ban of DDT in Canada in 1969 and in the United States three years later, its effects have been slowly diminishing. DDT residues in Alberta birds are now at their lowest levels since scientists started collecting data from eggshells in 1968. "Back then, we were seeing DDT levels as high as 14 ppm (parts per million)," says Court. "Now it’s down to about four ppm. We rarely come across a seriously contaminated bird." Since the ban on DDT, peregrines have been making a remarkable comeback around the world. In April, Canada upgraded the status of the peregrine from endangered to threatened. In August, the United States removed the bird from its endangered species list. There are about 50 pairs nesting throughout Alberta — a little more than half the historic levels. The ban on DDT alone may not have amounted to much if an Edmonton based Canadian Wildlife Service scientist hadn’t had the foresight in the late 1960s to start the captive breeding program that was eventually based at Wainwright. Although the program was shut down in 1996, its legacy continues at smaller facilities in Black Diamond, Saskatoon and Ste. Anne de Bellevue, Quebec. Convinced that DDT was going to spell the end for the peregrine, Richard Fyfe came up with the idea of collecting young chicks from the few remaining nesting pairs in the wild and breeding them in captivity. When the day arrived that DDT was no longer a threat, the birds would be released back into the wild. As visionary as the idea turned out to be, he had a tough time selling it to both the scientific community and the public. But the tide turned when Fyfe met with delegates attending a federal provincial wildlife conference in Yellowknife in 1970. The following year, Fyfe and Harry Armbruster scoured Northern Alberta and the Mackenzie Valley for birds. Fyfe ended up housing some 40 peregrine, gyr and prairie falcons at his acreage until the breeding facility could be built at CFB Wainwright in 1973. The first fertile eggs were produced the following year, but not all went smoothly. Mating difficulties "The reality is that you can’t just put two birds together and expect them to mate," says Fyfe. "Peregrines are individuals with different personalities. Some peregrines wouldn’t have anything to do with the bird we tried to match it with. Others fought with each other, which is a serious thing considering how much bigger a female is than a male. It was hard to make a good match because these birds act quite differently when there are people around watching." Fyfe credits summer student Tom Donald for solving the matchmaking problem. "He suggested that we put closed circuit televisions in with the peregrines so we could monitor for compatibility and behaviour problems without interfering. It worked out quite well." Releasing them into the wold proved to be another obstacle. About 250 captive raised birds were released in artificial boxes on highrise towers and cliffsides between 1975 and 1985, but only a handful returned from the migration the following year. "No doubt a number were lost to predators and the many dangers associated with the long migration south," Court says. "But the reality is the DDT levels in the peregrines and their prey were still too high at the time." It wasn’t until the 1990s that scientists began to see the payoff. A big breakthrough came in 1992, when Arrow, one of Alberta’s most famous urban falcons, produced a healthy clutch of eggs after 11 years as an unsuccessful breeder. "Hers was a story we began to see all across the country," Court says. "Their success corresponded almost perfectly with the drops in DDT residues that we were documenting everywhere." Biologists like Fyfe and Court are gratified the peregrines are expanding their ranges outside the boxed nest environment of highrise city towers to their traditional cliffsides. "The distribution of prairie falcons and peregrines that we’re seeing today in the Valley of the Falcons is what you would have expected to see back in the 1950s before the DDT took its toll," said Court. "In many cases, they’re nesting on the same cliffsides they nested 40 years ago."
Later that day in the Valley of Falcons, Court, naturalist Dick Dekker and biologist Rob Corrigan came across a pair of peregrines hovering over an empty nest. The chicks had been killed by a predator. "The female was just feeding the air when I saw her," said Court. "She was so primed to be a parent she was going through the motions even though there wasn’t a chick there." Sensing an opportunity, Court and Dick Dekker hurried to Tofield to pick up a chick being raised in captivity by commercial falcon breeder Phil Trefry. A week after Court slipped the young bird into the nest in the Valley of the Falcons, he returned to see how it was doing. "It was so fat, I thought it was going to explode, so I headed back and got two more chicks. They were all doing well the last time we checked in on them." As optimistic as they are, no one in the scientific community believes the threat is over. For 19 years, Court and other scientists have been monitoring a population of tundra peregrines on the islands and west shore of Hudson Bay near Rankin Inlet in Nunavut Territory. Unlike falcons elsewhere in the world, the levels of contamination in these birds remain relatively high. For some time, Court and his colleague Robin Johnstone were at a loss for explanations, especially when similar tundra peregrines nesting in Alaska and Greenland, and migrating from similar locales in South America, were proving to be relatively clean of contamination. Then it dawned on them the one big difference was the bird’s diet. Where the Greenland and Alaska peregrines preferred passerines or perching birds for food, those from Rankin were hitting on old squaw ducks and guillemots, neither of which migrate to the neotropical regions. Subsequent tests showed the two species — which overwinter near the Great Lakes, where contamination is still a problem — were showing high levels of organochlorines. The big challenge for scientists now is to focus on the kind of research that was virtually impossible when the peregrine was on the brink of extinction. One tool they have is satellite technology. Biologists can now place tiny transmitters on the peregrines to track their migration and movements on the wintering grounds. Canadian Wildlife Service scientist Geoff Holroyd has already tracked two Northern Alberta peregrines in this way. The first ended up wintering in the Gulf of Mexico region in Mexico. The second died in Hurricane Mitch last year. Holroyd has equipped two more Northern Alberta birds this year. He also provided Court and the Alberta government with tow tiny transmitters to put on birds in downtown Edmonton. Court has nicknamed one "The Flying Scalpel," out of respect for her ferocity. The female falcon took over Arrow’s nest site on the Telus building after battling and decapitating another female who had been occupying her nest. The transmitter has evidently not slowed down the bird. "The day after we put the transmitter on her, I went out on the ledge and she just powdered me," said Court. "Fortunately, I had a motorcycle helmet and visor on." Even before the bird headed south this year, Court was getting astonishing information from the satellite transmitters. "We now know that they’ll go as far as Smoky Lake in a day to hunt," says Court. "That explains a lot because for some time we couldn’t figure out where they were getting some of the prey that they were bringing back to the nest." Honours in the U.S. One of the ironies of this great Canadian success story is that Fyfe’s role has gone almost unnoticed in this country. The United States, however, recently honoured Fyfe at a huge party organised by the National Geographic Society to celebrate the fact the peregrine is no longer endangered south of the border. "It was big news down there when they took it off the endangered species list. I don’t understand why we can’t celebrate when we do something right. I guess it’s all part of being Canadian." The U.S. Fish and Wildlife Service has a plan that could see the harvesting of some 250 peregrine falcons in the near future — birds that would eventually go to falconers. The Canadian government objects on the basis that some of its migrating birds could be captured in the harvest. |
A Dwindling Legacy: Cover Story