This 340-year-old bow was reconstructed from several fragments found near melted patches of ice in the Mackenzie Mountains in the Northwest Territories. (Tom Andrews) Melting ice pockets high in Canada's Arctic mountains are slowly revealing the habits of caribou hunters over thousands of years as they moved from attacking with spears to bows and arrows — and even set traps to snare smaller snacks while they waited for their main prey.

Since 2005, archeologist Tom Andrews and colleagues have been piecing together how hunters in the area adapted over many generations, studying bits of tools grabbed from melting snowy patches in the remote Mackenzie Mountains in western Northwest Territories along the Yukon boundary.

Mountain boreal caribou have long sought refuge on the cooling patches, escaping annoying bugs and warmer temperatures over the summer months. Over generations, humans learned to hunt them there and have left tools buried deep beneath years and years of winter snow.

Now, said Andrews, the ice patches are slowly receding each year, likely due to global warming, revealing perfectly preserved relics of the past.

"It's very exciting," he said, adding that tools found in other parts of the region not protected by layers of snow and ice have been eaten away by acidic soils and tell an incomplete story.

"It's very rare that we get to find artifacts that are so well preserved."

Researchers have been able to remove pieces of the ice stratified with layers of winter snowfall and caribou dung. The oldest pieces date back as far as 6,000 years.

Andrews, who works at the Prince of Wales Northern Heritage Centre in Yellowknife, said the melting ice has revealed a piece of a dart that would have been used with a spear dating back 2,400 years. They've also found bows and arrows more than 800 years old.

As a result, they've been able to figure out that hunters in the region adapted the technology from spears to arrows over time, rather than using both types of tools at once.

"We were never really sure about what hunting technologies were used, so we can confirm that spear throwers and darts were used, and also bow and arrow technology, although it seems one technology supplanted the other," he said.

Setting traps

They also discovered a broken stick alongside a two-ply twisted cord of sinew — proof that 1,000 years ago, people were setting traps for ground squirrels while they waited to capture their bigger prey.

Andrews said he has worked closely with aboriginal people in the region, including the Tulita Dene band.

Leon Andrew, a band member and brother of the chief, said he has been involved with the research from the beginning.

He said he's astounded to watch perfectly formed pieces emerge from the ice, with sinew dating back hundreds of years looking as good as new.

"We hear all kinds of traditional stories, but we have no method of backing it up. Now we have some details about arrowhead making, etc., and can actually see how the stones are made," he said.

"It kind of opens up our history."

Andrews said his group is funded only through this summer after an original grant from federal International Polar Year funding.

He said it's essential to continue closely watching the patches each August as they slowly shrink, revealing fragile fragments of our past.

"The (pieces) dry out quite rapidly, and that can lead to cracking and breaking. And these places are very windy and they're light, and once they dry out it wouldn't take long before they would just completely disappear," he said.

"It's quite urgent. We have to make sure we're there to collect these things almost as they come out."