While only 30 of 150 ultrasonically tagged fish have been detected to date, these early data suggest that many young salmon are surviving their migration north to feed and grow in waters of the Labrador Sea, coastal West Greenland and northern Canada.
"Given the fact that we are looking for a fish that is still less than a foot long that could be anywhere in the Northwest Atlantic Ocean, finding them in such apparent concentrations hundreds of miles from Brewer, Maine is remarkable and very encouraging," Kocik said. "Broad-scale ocean arrays such as the Halifax Array are a great tool to examine the marine ecology of such an uncommon fish in a large marine environment."
NEFSC biologists used ultrasonic tags to track wild-origin Atlantic salmon in Maine's Narraguagus River system and estuary from 1997 to 1999 and again from 2002 to 2004. More recently, telemetry operations moved to the Penobscot River to look at a larger marine system and to study the largest Atlantic salmon population in the U.S.
The current project, scheduled to run through 2010, is designed to look at the emigration survival and ecology of smolts of different hatchery origins, such as those fish that are naturally reared spending two years in a river or those stocked from a hatchery just weeks before migrating to the ocean.
Kocik and his colleagues in the NEFSC Atlantic Salmon Task are looking primarily at marine losses of Atlantic salmon to try to determine what is causing so many salmon to die at sea. "Telemetry is only one tool we use," Kocik said of the current ultrasonic tagging efforts. "We have three scientists in the Labrador Sea right now working with Canadian colleagues as part of the international Salmon at Sea (SALSEA) project to determine where Atlantic salmon are and are not, and to try to get detailed genetic and dietary information about the various North Atlantic salmon stocks. "
Global monitoring efforts like the Ocean Trackin
|Contact: Shelley Dawicki|
NOAA National Marine Fisheries Service