And then there were none: Last 2 wolves leave Banff's Bow Valley

They were shot for seeking human food. Their pups were hit by trains. Now the last two remaining members of Banff National Park's Bow Valley pack have moved on.

Parks Canada staff estimated the pack had at least nine wolves in the spring of 2016.But the wolf pack startedgetting introuble last year when the animals became used to human food and lingered near campgrounds.

JesseWhittington,a wildlife ecologist with Banff National Park, saystwo of the wolves were shot by Parks Canada officersfor aggressive behaviour. A third was shot by a hunter outside the park in southeastern British Columbia.

None of the pack's pups survived. Four of them werekilled by trains.

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The remaining male, who has a GPS collar,has now joined a pack of four or five wolvesin the southernpart of the park. It'scalled the Spray pack.

That male's two-year-old female offspring"hooked up" with another male wolfthissummer, buthasn't been spotted recently, Whittington said.

She has an olderVHF-only radio collar that has to be picked up by scanners on the ground.

It's common for wolves who are two and a half years old to leave the pack. The hot weather this summer might have also played a role in her disappearance.

"Wolves often in the summertimewill travel up to the higher elevations. They will take their pups up there. They'll hunt up there, in part, especially this summer. It's cooler there, but that's also where a lot of the elk, deer, and moose go," said Whittington.

"Last summer was very unusual for us. Normally wolves travel up to the high elevations. You don't seethem in the valley bottom at that time of year. But that pack became food conditioned and they were constantly in our campgrounds, close to the campsites, looking for human food."

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Whittington expects wolveswill eventually move back intothe Bow Valley because there is a lot of wildlife to feedon.

"There's quite a lot of prey out there. Not as many elk as we had out there 20 years ago there's elk, deer, moose, big horn sheep, mountain goats. And wolves prey on all those species.I'm certain at some point in the next year or two we will have a full-fledged Bow Valleypack again."

Wolves from outside the valley will need to learn how to navigate the busy landscape, using the wildlife under- and overpasses, he added.

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