Moose die-off mystery tackled with high-tech tracking

The B.C. government is hoping to find out more about why moose numbers are declining by tagging the animals with devices that will allow biologists to track them down when they die.

Doug Heard, a wildlife biologist with the B.C. provincial government, told CBC's Daybreak North that his department will be radio-collaring 240 moose calves in the central Interior as part of the life-and-death monitoring study.

"One needs to be careful, but we have a system for doing it," he said.

Some of the moose will be darted and tranquilized, but a substantial number will be caught from the air.

"We'll net them from a helicopter — shoot a net over the moose, from a helicopter," Heard said. "Once the moose gets tangled up, we'll go and handle the moose and put the collar on and let it go."

The radio collar monitoring system will trigger an email alert to provincial wildlife biology staff when the moose stops moving for more than 24 hours.

Staff will then mobilize to attempt to find the presumed-dead animal's body. About 10 per cent of the collared moose are expected to die each year of the study, which should last for the approximate life of the collars — around five years.

Heard said predators could complicate matters, as wolves feeding on the body of a dead moose might move the collar around, but the study should still yield important clues as to what is contributing to the decline of moose near and far.

"In many parts of the central Interior, moose numbers were much lower in 2011 than in previous years, specifically 2005 and the late 1990s," Heard said. 

"In a more general picture, moose numbers have been declining in many parts of North America and even in Europe. There might be big broad generalities that we're going to find here."

The study is being split among eight regions — ranging from Kamloops to Smithers, to Mackenzie and Prince George — with around 30 animals selected in each of the regions, and biased towards the females.

"The survival of female moose is the most influential factor affecting overall moose population dynamics," Heard said.