A new study aims to research how salmon use magnetic fields for navigation and determine whether mineral stores like the Pebble deposit in Bristol Bay, Alaska might help guide the fish back to their spawning grounds.
The study will be carried out by Nathan Putman, a scientist at LGL Ecological Research Associates and an expert in how animals use magnetic fields in migration.
“Scientists are only beginning to understand how salmon rely on the earth's magnetic field in a map-like way to assess where they are along their migratory pathway and in a compass-like way to maintain a heading during their movements,” Putman said.
The study is being funded by Wild Alaskan Company, a direct-to-consumer seafood membership company founded by third-generation Bristol Bay fisherman Arron Kallenberg.
“We started with a really simple question: Given that salmon rely on the earth's magnetic field to navigate, is it a coincidence that one of the largest mineral deposits in the world happens to be located near the largest sockeye salmon spawning grounds in the world?” Kallenberg said.
The Pebble deposit is among the world’s largest untapped caches of copper and gold ore and is nestled among spawning grounds in Bristol Bay, home to world’s largest sockeye salmon run. In November, the Army Corps of Engineers denied developers a permit for an open pit mine in the region.
The decision was seen as a win for the sockeye salmon fishery in Bristol Bay, but lasting protections have yet to be granted by the federal government. Global mineral demand and the scope of the deposit mean developers will continue to pursue extraction of the Pebble deposit. Kallenberg said Putman’s previous research has suggested that the Pebble ore may in fact be fundamental in helping sockeye find their way back to their spawning grounds, and could provide another reason to scuttle the mine proposal.
“Everyone can agree that it would be prudent to obtain a definitive answer before extracting a mineral deposit that might be playing a necessary role in allowing the fish to find their way home and reproduce,” Kallenberg said.
According to a press release from Wild Alaskan, previous laboratory research by Putman indicates that changes in the magnetic field caused by humans have the potential to disrupt salmon’s ability to return to spawning grounds.
Photo courtesy of liveyourlife/Shutterstock
