08 Feb 2013:
Memory of Magnetic Landscape
Guides Salmon to Home Rivers, Study Shows
Although magnetism has been known to play a role in the remarkable homing ability of salmon, a new study clarifies just how the fish use magnetic fields
to travel thousands of miles to their natal rivers to spawn. Researchers at Oregon State University solved this mystery by studying 56 years of fishery data involving the millions of sockeye salmon that annually pour into British Columbia’s Fraser River. Vancouver Island sits in front of the Fraser, and the routes the salmon took around the island in different years offered clues to how the fish decipher shifting magnetic fields. When the magnetic field of the northern passageway around Vancouver Island was similar to that experienced by the fish when they left the river two years earlier, the returning salmon tended to chose the northern route;
the reverse was true when there was a more southerly magnetic field. Lead researcher Nathan Putnam said this showed that juvenile salmon imprint on the magnetic signature of their home rivers and then seek their way back using that signature. “When the sockeye leave the Fraser as juveniles, that first encounter with salt water is like a kick in the face,” said Putnam, whose research was published in Current Biology
. He said the message to the salmon is, “This is important. You have to remember this magnetic map. And they do.”
Yale Environment 360 is
a publication of the
Yale School of Forestry
& Environmental Studies
Yale Environment 360
articles are now available in Spanish and Portuguese on Universia
, the online educational network. Visit the site.
Business & Innovation
Policy & Politics
Pollution & Health
Science & Technology
Antarctica and the Arctic
Central & South America
The 2015 Yale e360 Video Contest winner documents a Northeastern town's bitter battle over a wind farm. Watch the video.
is now available for mobile devices at e360.yale.edu/mobile
A 2015 Yale e360 Video Contest winner captures stunning images of wild salmon runs in Alaska. Watch the video.
video goes onto the front lines with Colorado firefighters confronting deadly blazes fueled by a hotter, drier climate. Watch the video.
A three-part series Tainted Harvest
looks at the soil pollution crisis in China, the threat it poses to the food supply, and the complexity of any cleanup. Read the series.
Top Image: aerial view of Iceland
. © Google & TerraMetrics.