About  |   Contact  |  Mongabay on Facebook  |  Mongabay on Twitter  |  Subscribe
Rainforests | Tropical fish | Environmental news | Blog | For kids | Madagascar | Photos | Non-English languages | Tropical Conservation Science | Jobs
SHARE:




Warming could bring sharks to Antarctica with devastating ecological consequences
mongabay.com
February 15, 2008




Global warming could make the waters around Antarctica hospitable to sharks for the first time in 40 million years. Their return could have devastating ecological consequences report researchers from the University of Rhode Island.

Analyzing the physiological adaptations and metabolism of sharks and other predators, Cheryl Wilga and Brad Seibel found that an increase of just a few degrees Celsius could make Antarctic waters habitable for Benthic sharks, species that live on the seafloor and swim very little. Ocean-going sharks, which have a high metabolism rate because they must swim constantly to aerate their gills, would not survive in the cold waters around Antarctica.

Still Wilga and Seibel say that because "they cannot swim great distances and do not produce a larval stage capable of wide dispersal, it is unlikely [Benthic sharks] could easily get to Antarctica on their own."

Nevertheless, should sharks reach the Antarctic, they would likely have a significant ecological impact say the researchers.


Though it lives in cold waters, the leopard shark could not survive in the Antarctic. Unlike benthic sharks, the leopard shark must swim constantly to aerate their gills, requiring a high metabolism and large amounts of energy.
"There are few prey-crushing predators in Antarctic waters. As a result, the Antarctic seafloor has been dominated by relatively soft-bodied, slow-moving invertebrates, just as in ancient oceans prior to the evolution of shell-crushing predators." said Wilga. "The water only needs to remain above freezing year round for it to become habitable to some sharks, and at the rate we're going, that could happen this century. Once they get there, it will completely change the ecology of the Antarctic benthic community."

Wilga and Seibel that shrimp, ribbon worms and brittle stars will likely be the most vulnerable to population declines should sharks make it to the Antarctic.

"Ice fishes — the only bony fish that now lives in Antarctic waters, because it has antifreeze in its system — will face a new threat as well," Wilga added. "They are already preyed upon by seals and penguins. Adding sharks and other bony fishes to the mix will likely have a big affect on them."

Warming seas could also help crabs. Currently "cold Antarctic water reduces their ability to flush magnesium from their blood, leading to magnesium narcosis and death", according to a statement from the University of Rhode Island, but higher temperatures are enabling crabs to closer to the Antarctic.

The waters around the Antarctic Peninsula have warmed by 1 to 2 C in the last 50 years, a rate that is about double or triple the global average.

Wilga and Seibel's study, "None Like It Cold: Physiological Constraints on Predators in Antarctica," was presented today in Boston at the annual meeting of the American Association for the Advancement of Science.














CITATION:
mongabay.com (February 15, 2008). Warming could bring sharks to Antarctica with devastating ecological consequences. http://news.mongabay.com/2008/0215-sharks.html


Tags:
sharks ecology impact of climate change pollution Invasive Species oceans Antarctica environment green

print


News index | RSS | News Feed | Twitter | Home


Advertisements:


Organic Apparel from Patagonia | Insect-repelling clothing




Mongabay Store
Wildlife of Madagascar T-shirt
Wildlife of Madagascar T-shirt
Bold and Dangerous - Pygmy tyrant t-shirts
Bold and Dangerous - Pygmy tyrant
Love me before I'm gone - Gladiator frog t-shirts
Love me before I'm gone - Gladiator frog
Licking this frog may make you crazy t-shirts
Licking this frog may make you crazy





WEEKLY NEWSLETTER
Email:





SUPPORT
Mongabay.com seeks to raise interest in and appreciation of wild lands and wildlife, while examining the impact of emerging trends in climate, technology, economics, and finance on conservation and development (more)

Help support mongabay.com when you buy from Amazon.com



POPULAR PAGES
Rainforests
Rain forests
Amazon deforestation
Deforestation
Deforestation stats
Why rainforests matter
Saving rainforests
Deforestation stats
Rainforest canopy

News
Most popular articles
Worth saving?
Forest conservation
Earth Day
Poverty alleviation
Cell phones in Africa
Seniors helping Africa
Saving orangutans in Borneo
Palm oil
Amazon palm oil
Future of the Amazon
Cane toads
Dubai environment
Investing to save rainforests
Visiting the rainforest
Biomimicry
Defaunation
Blue lizard
Amazon fires
Extinction debate
Extinction crisis
Blackwashing
Industrial deforestation
Save the Amazon
Rainforests & REDD
Brazil's Amazon plan
Malaysian palm oil
Avatar story
New Guinea
Sulawesi
Amazon ranching
Madagascar
Borneo

News topics
Amazon
Biofuels
Brazil
Carbon Finance
Conservation
Climate Change
Deforestation
Energy
Happy-upbeat
Indonesia
Interviews
Oceans
Palm oil
Rainforests
REDD
Solutions
Wildlife
MORE TOPICS



Non-English Sites
Chinese
French
German
Greek
Indonesian
Italian
Portuguese
Spanish
Other languages

Nature Blog Network









Photos
Alaska photos
Alaska

Argentina photos
Argentina

Australia photos
Australia

Belize photos
Belize

Brazil photos
Brazil

Cambodia photos
Cambodia

China photos
China

Colombia photos
Colombia

Costa Rica photos
Costa Rica

Deforestation photos
Deforestation

Frog photos
Frog

Gabon photos
Gabon

Grand Canyon photos
Grand Canyon

Honduras photos
Honduras

India photos
India

Indonesia photos
Indonesia

Kenya photos
Kenya

Laos photos
Laos

Lemur photos
Lemur

Madagascar photos
Madagascar

Malaysia photos
Malaysia

Monkey photos
Monkey

New Zealand photos
New Zealand

Panama photos
Panama

Peru photos
Peru

Peru photos
Rainforest


Sunset

Suriname photos
Suriname

Tanzania photos
Tanzania

Thailand photos
Thailand

Uganda photos
Uganda

United States photos
United States

Venezuela photos
Venezuela



HIGH RESOLUTION PHOTOS / PRINTS


CALENDARS
  • Mount Kenya
  • East Africa Safari Wildlife
  • Kenya's Turkana People
  • Peru
  • African Wildlife
  • Alaska
  • China
  • Madagascar Chameleons


    CANVAS BAGS

  • Hallucinogenic frog bag
  • Madagascar wildlife bag








  • Copyright mongabay 2010

    Carbon dioxide (CO2) emissions generated from mongabay.com operations (server, data transfer, travel) are mitigated through an association with Anthrotect,
    an organization working with Afro-indigenous and Embera communities to protect forests in Colombia's Darien region.
    Anthrotect is protecting the habitat of mongabay's mascot: the scale-crested pygmy tyrant.