William Josie is watching dramatic changes in weather and animal behaviour unfold in Yukon’s most northern community of Old Crow.

Josie, the executive director of the Vuntut Gwitchin First Nation, thinks much of the shift has to do with the effects of climate change.

He and his family spend a lot of time hunting and trapping at their camp at the mouth of the Driftwood River, about 85 kilometres up the Porcupine River.

William Josie dries chum salmon at his family's camp at the mouth of the Driftwood River in northern Yukon. (Peter Mather) Post image on Pinterest: William Josie dries chum salmon at his family's camp at the mouth of the Driftwood River in northern Yukon. (Peter Mather)

William Josie dries chum salmon at his family's camp at the mouth of the Driftwood River in northern Yukon. (Peter Mather)

“The biggest change I’ve seen in the past 20 years is the weather. We seem to be getting warmer winters, we have open water in lakes and rivers, longer and wet summers," says Josie.

He says the caribou are now staying north of the Porcupine River during the fall, and in winter the majority stay in Arctic Village in Alaska.

Last fall, Josie says the herd stayed in the Vuntut National Park and special management areas, about 85 kilometers north of where they usually are. That meant hunters had to go up the Old Crow River to find them.

The pink area shows the current migration range of the Porcupine caribou herd; yellow is the boundaries of the Arctic National Wildlife Refuge; orange shows where the two overlap. Post image on Pinterest: The pink area shows the current migration range of the Porcupine caribou herd; yellow is the boundaries of the Arctic National Wildlife Refuge; orange shows where the two overlap.

The pink area shows the current migration range of the Porcupine caribou herd; yellow is the boundaries of the Arctic National Wildlife Refuge; orange shows where the two overlap.

The changes Josie is seeing suggest a shift in animals’ traditional habitat, as weather patterns change throughout the territory.

He thinks caribou are moving farther north to escape the effects of climate change, specifically an increase in wet weather.

Josie says there’s a lot more rain and it lasts longer, from the summer to well into the fall. So the ground is freezing up, virtually sealing off lichens, an important food source for caribou in winter.



“There is a bigger moose harvest in Old Crow because it’s harder to get caribou in the fall," said Josie.

Josie says that shrubs are now growing north of the treeline and moose are following the food source farther north, so there are more of them to hunt around the community.



Mark O’Donoghue, a biologist with Yukon’s Fish and Wildlife branch, says this increased growth of shrubs due to climate change is attracting moose into what used to be primarily caribou habitat.

“The increase in shrub growth northwards into the tundra and higher up mountains is well-documented as temperatures warm.”



Yukon biologist Mark O'Donoghue says the increased growth of shrubs due to climate change is attracting moose into what used to be primarily caribou habitat. (Submitted by Mark O'Donoghue) Post image on Pinterest: Yukon biologist Mark O'Donoghue says the increased growth of shrubs due to climate change is attracting moose into what used to be primarily caribou habitat. (Submitted by Mark O'Donoghue)

Yukon biologist Mark O'Donoghue says the increased growth of shrubs due to climate change is attracting moose into what used to be primarily caribou habitat. (Submitted by Mark O'Donoghue)

O’Donoghue points out that a longer growing season stimulates more growth, and shrubs can then overtake other plants.



He also warns that human disturbances — things like forestry, or cutting seismic lines and roads for natural gas exploration — also help create shrubby conditions and drive caribou farther north.



“Definitely if you get some real rain during the winter time, that makes it hard for caribou to get at their food,” O’Donoghue said.

“They want the lichens in the ground and that can make them less accessible.

“Certainly in the far north that has been a cause of some die-offs of caribou when they have a lot of rain and they just can’t get food.”

Both caribou and moose seem to be moving farther north to escape the effects of climate change, specifically an increase in wet weather. (Peter Mather) Post image on Pinterest: Both caribou and moose seem to be moving farther north to escape the effects of climate change, specifically an increase in wet weather. (Peter Mather)

Both caribou and moose seem to be moving farther north to escape the effects of climate change, specifically an increase in wet weather. (Peter Mather)

'If they encounter some cold weather in the spring then they just die of hypothermia or pneumonia.'

And there are other threats to their food source — O’Donoghue says biologists are also watching the impacts of a changing fire regime due to climate change.

“If we end up with more frequent or intense fires, these would likely have side effects on caribou, which require lichens for winter food — these take at least 40 to 50 years to develop.”