In a Canadian archeological project that could revolutionize understanding of when and how humans first reached the New World, federal researchers in B.C. have begun probing an underwater site off the Queen Charlotte Islands for traces of a possible prehistoric camp on the shores of an ancient lake long since submerged by the Pacific Ocean.

The landmark investigation, led by Parks Canada scientist Daryl Fedje, is seeking evidence to support a contentious new theory about the peopling of the Americas that is gradually gaining support in scholarly circles. It holds that ancient Asian seafarers, drawn on by food-rich kelp beds ringing the Pacific coasts of present-day Russia, Alaska and British Columbia, began populating this hemisphere thousands of years before the migration of Siberian big-game hunters -- who are known to have travelled across the dried up Bering Strait and down an ice-free corridor east of the Rockies as the last glaciers began retreating about 13,000 years ago.

The earlier maritime migrants are thought to have plied the coastal waters of the North Pacific in sealskin boats, moving in small groups.

Over many generations, they migrated from their traditional homelands in the Japanese islands or elsewhere along Asia's eastern seaboard.

Interest in the theory -- which is profiled in the latest edition of New Scientist magazine by Canadian science writer Heather Pringle -- has been stoked by recent DNA studies in the U.S. showing tell-tale links between a 10,000-year-old skeleton found in an Alaskan cave and genetic traits identified in modern Japanese and Tibetan populations, as well as in aboriginal groups along the west coasts of North and South America.

The rise of the "coastal migration" theory has also been spurred by a sprinkling of other ancient archeological finds throughout the Americas -- several of them, including the 14,850-year-old Chilean site of Monte Verde, too old to fit the traditional theory of an overland migration by the "first Americans" that didn't begin for another millennium or two.

Proponents of coastal migration argue that Ice Age migrants in boats may have island-hopped southward along North America's west coast as early as 16,000 years ago, taking advantage of small refuges of land that had escaped envelopment by glaciers.

The difficulty is that nearly all of the land that might contain traces of human settlement or activity -- the critical proof for archeologists -- is now under water.

Several significant finds have been made in raised caves along the B.C. coast that were not inundated by the rising Pacific in post-glacial Canada.

In 2003, Simon Fraser University scientists reported the discovery of 16,000-year-old mountain goat bones in a cave near Port Eliza on Vancouver Island, and similar finds of prehistoric bear bones pre-dating the glacial retreat have been held up as proof of a shoreline ecosystem that could have sustained large mammals, as well as human hunters.

The new Parks Canada target is at a site in the Gwaii Hanaas National Park Reserve just north of Burnaby Island, near the southern end of the Queen Charlottes.

According to the New Scientist, Fedje has discovered evidence of a prehistoric lake and streambed about 50 metres below the surface at a site called Section Cove, as well as signs that the river and lake were once rich sources of salmon -- an "irresistible" food source for ancient coastal migrants.

"We are pretty positive that there will be an archeological site where we think it should be on that lake shore," Fedje told the British-based publication. "There's no reason why people couldn't have been on these old landscapes 14,000 or more years ago."