Scientists have proven new miniature tagging and tracking technologies can follow the travels of small salmon through vast distances and highly dissimilar waters - from as far as the Rocky Mountain headwaters of USA's Columbia River through the ocean to the coast of Alaska.
And, experts say, the breakthrough opens the way to reveal some of Mother Nature's most closely guarded secrets.
Over the last decade, researchers have used tags to follow larger ocean dwellers such as sharks, sturgeon, tuna and sea turtles, and to follow migrations of mature salmon along marine coasts.
Now for the first time they have tagged and directly tracked small juvenile Pacific salmon, from their release in freshwater far upriver to distant ocean destinations, a major step towards understanding the full life experience and decline of this species.
"It may have been one of humankind's first ponderings: the fish that got away - where they come from, where they go, and what happens to them in between," says Jim Bolger, Executive Director of the Pacific Ocean Shelf Tracking (POST) Project, part of the international Census of Marine Life and hosted by the Vancouver Aquarium.
"Until now it has been difficult to follow small animals in vast oceans, and it has only been possible to infer their movements using very indirect methods. Thanks to new sound-emitting tags about the size of an almond, combined with an extensive coastal network of underwater detectors from Alaska to California, several mysteries of fish migration and survival may soon start to unravel."
In 2006, researchers implanted the new tags in 1,000 juvenile Chinook salmon (www.eol.org/taxa/17154704) roughly the same length and half the weight of a frankfurter hot dog - 14 centimeters long, 20-30 grams weight - and followed their journeys in the Columbia and Fraser Rivers.
Among the many studied, two tagged juvenil
|Contact: Terry Collins|
Census of Marine Life