After decades of conservation efforts, Yukon biologists are celebrating the recommended removal of peregrine falcons from Canada's endangered species list.

The bird was listed as endangered in 1978, but now the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) says it should be considered a self-sustaining species.

"The peregrine was the first species that we dealt with at the COSEWIC level. And to see it now being de-listed is actually a wonderful time," said Dave Mossop, a member of the Yukon Research Centre and a professor emeritus at Yukon College. 

He's been involved with the conservation efforts of the peregrine since day one. He says in 1978, there was only one breeding pair of peregrines identified in southern Yukon.

Dave Mossop

'To see it now being de-listed is actually a wonderful time,' said Dave Mossop of the Yukon Research Centre. (Steve Hossack/CBC)

 "There was a bit of a crisis, obviously, among raptor biologists. The last [peregrine] youngsters that were being produced in our major population here in the Yukon were taken into captivity," he said.

"We have, now, well over 200 pairs." 

At first, he says, the reason for the decline of the peregrine population was unknown. Eventually, researchers linked the collapse to the insecticide DDT. The chemical was banned across North America in 1972. 

Marcel Gahbauer, who sits on the bird sub-committee of COSEWIC, says incredible efforts were made to revitalize the peregrine population.

"I think there were people probably, at one point or another, from pretty much every province and territory, involved in the recovery effort. Especially in the '70s and '80s, when it was in its earlier phases."

Yukoners involved in early conservation efforts

Mossop says Danny Nolan, founder of the Yukon Game Farm (now the Yukon Wildlife Preserve), played a crucial role in facilitating the earliest efforts to breed peregrines in captivity.

He says Nolan's facility was where Yukon's captive breeding program started.

"Nobody knew if it would work. Well, over several years of trying various things, we finally did get them breeding," Mossop said.

Those young falcons were returned to the wild. Mossop says they were probably among the first peregrines to be bred in captivity and subsequently released into the wild.

baby falcons south health campus

Yukoners got involved early in peregrine recovery efforts, breeding birds in captivity and releasing the young ones into the wild. (Ken Crebbin)

"By 1981, we were able to publish the very first paper out of the Yukon with a population that obviously was recovering," Mossop said.

Mossop says that in the early 80's the peregrine population in north-central Yukon was stabilizing on its own, while birds bred in captivity were being released throughout southern Yukon. Further north, it was a different story. 

"At that time, the birds on the North Slope went to zero. There was no birds, no peregrines, left on the North Slope at all," Mossop recalls.

He says birds bred in captivity in southern Yukon were released on the North Slope, in hopes of revitalizing the population. Now, he says, there are now roughly a dozen pairs of breeding peregrines there.

"It's been one of the most, I don't know, happiest conservation issues you could possibly get involved with ... Given half a chance, it's amazing what natural populations will do. And the recovery has been absolutely astounding."

Concerns remain

But Mossop isn't entirely convinced the peregrine's fight for survival is over.

The bird is still considered a species of special concern on the Pacific coast.

"I have a bit of a worry. You know, you always do, because this bird, we know, is in harm's way. It's a bird that almost went extinct. So that bird is always going to be of special concern in my mind," Mossop said.

One concern he has is the peregrine's apparent struggle to reproduce. He says surveys in the Yukon suggest only about 20 per cent of breeding pairs actually produce offspring.

"So what does that mean? You know, I worry about these things."

Mossop says peregrines rely on wetlands, and wetland habitat is under threat in many parts of the world. Another concern is the decline in shorebird populations — a key food source for peregrines. 

"So to say that bird isn't under any kind of threat, it worries me just a little bit," Mossop said.

"But based on the number of adults, you know, that are on the land — it's a good news story."