Mercury levels in Arctic seals may be linked to global warming

Apr 29, 2009
Researchers are reporting that high mercury levels in Arctic seals appear to be linked to vanishing sea ice caused by global warming. Credit: National Oceanic and Atmospheric Administration.

Researchers in Canada are reporting for the first time that high mercury levels in certain Arctic seals appear to be linked to vanishing sea ice caused by global warming. Their study, a new insight into the impact of climate change on Arctic marine life, is scheduled for the May 1 issue of ACS’ Environmental Science & Technology.

Gary Stern and colleagues note in the new study that Canadian Arctic ringed seals, like many Arctic marine animals, have relatively high levels of mercury. However, researchers have never determined how these levels are linked to extent and the resulting composition of arctic cod and other prey containing mercury available to ringed seals.

The scientists analyzed the mercury content in muscle samples collected from ringed seals between 1973 and 2007. They then compared the levels to the length of the so-called “summer ice-free season,” a warm period marked by vanishing sea ice in the seals’ habitat. They found that the seals accumulated more mercury during both short (2 months) and long (5 months) ice-free seasons and postulate that this is related to the seals’ food supplies.

Higher seal mercury concentrations may follow relatively short ice-free seasons due to consumption of older, more highly contaminated Arctic cod while relatively long ice-free seasons may promote higher pelagic productivity and thus increased survival and abundance of Arctic cod with the overall result of more fish consumption and greater exposure to mercury. Longer ice-free seasons resulting from a warming Arctic may therefore result in higher mercury levels in ringed seal populations as well as their predators (polar bears and humans).

More information: Environmental Science & Technology, “ Trends in Ringed Seals (Phoca hispida) from the Western Canadian Arctic since 1973: Associations with Length of Ice-Free Season”

Provided by ACS

Explore further: Invasive vines swallow up New York's natural areas

add to favorites email to friend print save as pdf

Related Stories

Polar bears at risk from ice loss

Oct 14, 2005

Survival of the remaining polar bears is increasingly jeopardized by rapid disappearance of the arctic sea ice, conservation groups say.

Arctic global warming may be irreversible

Mar 14, 2006

Scientists, noting sea ice in the Arctic has failed to form for the second consecutive winter, fear global warming may be irreversible in polar areas.

NASA Sees Rapid Changes in Arctic Sea Ice

Sep 13, 2006

NASA data shows that Arctic perennial sea ice, which normally survives the summer melt season and remains year-round, shrunk abruptly by 14 percent between 2004 and 2005. According to researchers, the loss of perennial ice ...

Mercury pollution causes immune damage to harbor seals

Oct 21, 2008

Methylmercury (MeHg), the predominant form of mercury found in the blood of marine mammals and fish-eating communities, could be more damaging to seals than has previously been thought. Research published in BioMed Central's ...

Recommended for you

Invasive vines swallow up New York's natural areas

15 hours ago

(Phys.org) —When Antonio DiTommaso, a Cornell weed ecologist, first spotted pale swallow-wort in 2001, he was puzzled by it. Soon he noticed many Cornell old-field edges were overrun with the weedy vines. ...

Citizen scientists match research tool when counting sharks

Apr 23, 2014

Shark data collected by citizen scientists may be as reliable as data collected using automated tools, according to results published April 23, 2014, in the open access journal PLOS ONE by Gabriel Vianna from The University of Wes ...

Researchers detail newly discovered deer migration

Apr 23, 2014

A team of researchers including University of Wyoming scientists has documented the longest migration of mule deer ever recorded, the latest development in an initiative to understand and conserve ungulate ...

How Australia got the hump with one million feral camels

Apr 23, 2014

A new study by a University of Exeter researcher has shed light on how an estimated one million-strong population of wild camels thriving in Australia's remote outback have become reviled as pests and culled ...

User comments : 2

Adjust slider to filter visible comments by rank

Display comments: newest first

GrayMouser
5 / 5 (1) Apr 29, 2009
New headline: Researchers link Global Warming with a lack of originality in science!
SDDuude
not rated yet May 02, 2009
I'm understanding now that global warming is why the sky is blue.

More news stories

Genetic code of the deadly tsetse fly unraveled

Mining the genome of the disease-transmitting tsetse fly, researchers have revealed the genetic adaptions that allow it to have such unique biology and transmit disease to both humans and animals.

Ocean microbes display remarkable genetic diversity

The smallest, most abundant marine microbe, Prochlorococcus, is a photosynthetic bacteria species essential to the marine ecosystem. An estimated billion billion billion of the single-cell creatures live i ...

Cell resiliency surprises scientists

New research shows that cells are more resilient in taking care of their DNA than scientists originally thought. Even when missing critical components, cells can adapt and make copies of their DNA in an alternative ...