'Little gardeners on the tundra': The surprising effect Arctic foxes have on our ecosystem

Manitoba researchers are illuminating the surprising effects predators like Arctic foxes have on our environment.

University of Manitoba Ph.D. candidate Sean Johnson-Bice is studying food web interactions between Arctic and red foxes, and their shared prey.

To help unravel the role Arctic foxes play in our ecosystems, a recent study Johnson-Bice worked on used satellite imagery from Wapusk National Park south of Churchill, Man. to observe vegetation in their dens.

The images showed dense, lush greenery where Arctic foxes made their homes.

The culprit behind these Eden-esque abodes?

Researchers found remnants from the prey Arctic foxes brought back to the den to feed their young, urination and defecation create a natural fertilizer that any green thumb would covet.

“All these nutrients get concentrated into one area, and it transforms their dens into these bright, green, lush patches on the tundra,” he said.

“You can think of them as little gardeners on the tundra.”

An Arctic fox den in Wapusk National Park is shown in an undated satellite image.

Most of the dens are decades old, passed on by Arctic foxes from generation to generation. However, they’re not always in use.

Johnson-Bice and the team monitored about 80 dens within the park and within any given time, only about 20 to 50 per cent of them were used. Still, their dense, green footprints remained.

ARCTIC FOX POPULATION STEADILY DECLINING: RESEARCHERS

Another study from the summer found that the Arctic fox population around Churchill, Man. has been on the decline steadily for the past several decades.

Researchers have pegged the primary cause as climate change, as it’s affecting rodent populations that Arctic foxes rely on for food and their ability to hunt seal pups on the thinning Hudson Bay sea ice.

“They’re kind of getting squeezed on both ends basically, and their prey base has collapsed essentially,” Johnson-Bice said.

- With files from CTV’s Rachel Lagacé