Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Copper making salmon prone to predators

10.07.2012
Findings have implications for brake pads, copper mines
Minute amounts of copper from brake linings and mining operations can affect salmon to where they are easily eaten by predators, says a Washington State University researcher. Jenifer McIntyre found the metal affects salmon's sense of smell so much that they won't detect a compound that ordinarily alerts them to be still and wary.

"A copper-exposed fish is not getting the information it needs to make good decisions," says McIntyre, a postdoctoral research associate in WSU's Puyallup Research and Extension Center. Her research, conducted for a University of Washington doctorate with colleagues at UW and the National Oceanic and Atmospheric Administration, appears in the latest issue of the journal Ecological Applications.

Earlier research showed that copper impacts a salmon's sense of smell. Other research showed that when a salmon's sense of smell is affected, its behavior changes.

McIntyre put the two together, exposing juvenile coho salmon to varying amounts of copper and placing them in tanks with cutthroat trout, a common predator. The results were striking.

Salmon are attuned to smell a substance called Schreckstoff. German for "scary stuff," it is released when a fish is physically damaged, alerting nearby fish to the predator's presence.

In her experiments, conducted in a four-foot-diameter tank, fish that weren't exposed to copper would freeze in the presence of Schreckstoff, making it harder for motion-sensitive predators to detect them. On average, half a minute would go by before they were attacked.

But salmon in water with just five parts of copper per billion failed to detect the Schreckstoff and kept swimming. They were attacked in about five seconds.

"It's very simply and obviously because predators can see them more easily," says McIntyre. "They're not in lockdown mode."

The unwary exposed fish were also more likely to be killed in the attack, being captured 30 percent of the time on the first strike. Unexposed fish managed to escape the first strike nearly nine times out of ten, most likely because they were already wary and poised to take evasive action.

McIntyre also noticed that the behavior of predators was the same whether or not they had been exposed to copper.

Copper finds its way into streams and marine waters from a variety of sources, including motor vehicle brake linings, pesticides, building materials and protective boat coatings. Actual amounts will vary from undetectable in rural or forested areas to elevated in urban areas, especially when runoff from a storm washes roads of accumulated brake dust and other contaminants.

With testimony from McIntyre's NOAA colleagues and others, the Washington State legislature in 2010 started phasing out copper brake pads and linings over the next 15 to 20 years. According to the state Department of Ecology, brake pads are the source of up to half the copper in the state's urban waterways.

McIntyre used concentrations of between 5 and 20 parts per billion but has sampled highway runoff with 60 times as much copper. Copper's effect is mediated by organic matter, which can make the metal unavailable to living things.

"My scenarios are potentially more like a hard-rock copper mining situation than storm water runoff, which typically carries dissolved organic matter along with the copper and other contaminants," McIntyre says.

Alaska's proposed Pebble Mine, for example, would produce tens of billions of pounds of copper near Bristol Bay, the largest sockeye salmon fishery in the world.

Jenifer McIntyre | EurekAlert!
Further information:
http://www.wsu.edu

More articles from Ecology, The Environment and Conservation:

nachricht Successful calculation of human and natural influence on cloud formation
04.11.2016 | Goethe-Universität Frankfurt am Main

nachricht Invasive Insects Cost the World Billions Per Year
04.10.2016 | University of Adelaide

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

Silicon solar cell of ISFH yields 25% efficiency with passivating POLO contacts

08.12.2016 | Power and Electrical Engineering

NTU scientists build new ultrasound device using 3-D printing technology

07.12.2016 | Health and Medicine

The balancing act: An enzyme that links endocytosis to membrane recycling

07.12.2016 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>