One summer long ago, hunters, probably carrying throwing sticks, stalked a herd of caribou that had retreated to a snow patch high above Kusawa Lake to escape the heat and insects.

Hiding behind a line of boulders along the upper edge of the snow patch, the hunters crept close enough to launch stone-pointed darts at the caribou and make their kill. Then they hauled the meat back down to their camp near Kusawa Lake for packing and processing.

Somehow, one of the darts was left behind, perhaps broken in the hunt or embedded in the body of a caribou that escaped the hunters. Five thousand years later, a biologist examining a newly-discovered deposit of ancient caribou dung at the edge of the melting snow patch found the broken dart, the remains of three feathers still tied to its shaft.

That discovery could add dramatically to our knowledge of human prehistory in the Yukon.

Yukon Heritage Branch archaeologists Greg Hare and Ruth Gotthardt have been studying the site near Kusawa Lake and others like it, and University of Alberta anthropology student Vandy Bowyer will base part of her doctoral thesis on the ice patch sites.

The Kusawa site was discovered late in the summer of 1997. Aerial surveys this summer have turned up 35 other, similar sites. All are high patches of permanent snow and ice that are melting because of recent warm temperatures to reveal deposits of caribou feces hundreds and thousands of years old.

"Regarding the archaeological significance of the ice patches , we are still really only talking in terms of potentials," says Greg Hare. "Only two of 36 ice patches with caribou dung deposits have been investigated, and both have contained cultural materials."

Radiocarbon analysis of the first summer's cultural material, the wooden dart, dated it at about 4400 years before present. The broken dart is 24.5 centimetres long and just over a centimetre across at its thicker end. Archaeologists estimate that the complete dart was no more than 50 centimetres long.

At first they assumed they had found an arrow, but its age puts that assumption in doubt. Evidence from elsewhere on the continent suggests that bow-and-arrow technology arrived in North America less than 4000 years ago, at a time when the Kusawa dart had already been buried in four centuries of snow and ice.

However, darts propelled by throwing sticks or whip slings predate the bow and arrow, and there is evidence for use of the whip sling (a string attached to a throwing stick) in the Tlingit and Southern Tutchone areas of southern Yukon and northern British Columbia.

The cultural material found in this year's survey is just as interesting, says Hare.

"This year's research resulted in the recovery of a complete lanceolate stone spear point, two incomplete (broken) stone spear points, and a second wooden dart shaft with sinew binding," he says. "We also found a number of apparent dart blanks -- round, straight pieces of wood as yet unmodified but probably destined to be made into darts."

The complete spear point is a unique find, says Hare, not just for its style and condition, but also because it appears to have been smeared with a coating of red ochre, a powdered mineral.

"We're hoping that, in order to apply the ochre, these early hunters mixed it with some kind of fat or grease," Hare says. "The addition of an organic substance might allow us to radiocarbon date the spear point."

It appears to be about 5,000 years old, he says, based on the style and workmanship. However, radiocarbon dating of any grease mixed with the ochre and of the broken dart found this year will provide a clearer idea of how long ago those ancient hunters lived.

This summer's work has barely sampled the potential information to be gathered from the 36 sites already discovered and others that might still be found, says Hare.

"This may be an excellent opportunity to refine our understanding of the archaeological record in Yukon," he says.

For more information, contact Greg Hare at the Yukon Heritage Branch, greg.hare@gov.yk.ca.