10 Jul 2012:
Salmon More Susceptible to
Predators After Copper Exposure
Exposure to even tiny amounts of copper can impair a salmon’s ability to detect and evade predator species
, a new study has found. While salmon typically become still and alert after they smell a compound called Schreckstoff, which is released when a fish is damaged nearby, Washington State University (WSU) researchers say fish exposed to just five parts of copper per billion are unable to detect the substance, making them more vulnerable to attack. In a series of tests conducted in a four-foot diameter tank, salmon that weren’t exposed to copper would freeze after smelling the Scheckstoff, delaying by 30 seconds, on average, attack from cutthroat trout also swimming in the tank. Fish swimming in tanks containing copper, however, continued to swim, and were attacked by predators in about five seconds. “A copper-exposed fish is not getting the information it needs to make good decisions,” said Jenifer McIntyre, a WSU researcher and lead author of the study, published in the journal Ecological Applications
. These findings could mean that fish could face greater risk in the wild after exposure to copper from stormwater runoff or mining operations, such as the proposed Pebble Mine near Bristol Bay, Alaska, home to the world’s largest sockeye salmon fishery.
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
Tribal people and ranchers join together to stop a project that would haul coal across their Montana land. Watch the video.
is now available for mobile devices at e360.yale.edu/mobile
The 2015 Yale e360 Video Contest winner documents a Northeastern town's bitter battle over a wind farm. Watch the video.
A 2015 Yale e360 Video Contest winner captures stunning images of wild salmon runs in Alaska. Watch the video.
video series looks at the staggering amount of food wasted in the U.S. – a problem with major human and environmental costs. 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.