Sea otters help keep oceans healthy

2012-09-12 12:39
Sea otters are warding off the accumulation of acidic carbon dioxide in Alaska's waters by preying on sea urchins. (Reed Saxon, AP)

Sea otters are warding off the accumulation of acidic carbon dioxide in Alaska's waters by preying on sea urchins. (Reed Saxon, AP)

Multimedia   ·   User Galleries   ·   News in Pictures Send us your pictures  ·  Send us your stories

kalahari.com

  • Climate Change
    Read more about the environmental changes and challenges the world faces. Now R261.00
    buy now
Anchorage - Sea otters are warding off the accumulation of acidic carbon dioxide in Alaska's waters by preying on sea urchins that feed on underwater kelp beds vital to the oceans' health, according to a study.

Otter-protected kelp beds absorb about 12 times as much carbon dioxide during photosynthesis as thinned-out kelp beds, according to a study published in the September issue of Frontiers in Ecology and the Environment.

Atmospheric carbon dioxide threatens marine environments because the gas, when absorbed into the ocean, increases acidity levels, causing the phenomenon known as "ocean acidification", according to scientists. So by devouring sea urchins, otters allow the kelp to grow and keep the oceans cleaner.

Urchin-eating sea otters produce a significant savings, according to the study's authors, who said it would cost between $205m to $408m to offset the carbon that sea otters enable kelp beds to absorb, based on prices used in the European Carbon Exchange.

The study relied on data collected over 40 years from sites between British Columbia, Canada, and Alaska's Aleutian Islands.

Near extinction


Co-author Jim Estes said he hopes the study will help people understand that sea otters have far-reaching benefits.

"On the one side, people like sea otters because they're fuzzy, cool things. On the other side, a lot of people hate them," said Estes, a biologist and sea-otter expert at the University of California at Santa Cruz.

Fishermen, including shellfish harvesters, "are, without question, significant competitors" and famously hostile to sea otters, Estes said.

But by preserving kelp forests, otters benefit fishermen because kelp beds provide an important fish habitat, he said.

Sea otters were once hunted nearly to extinction, victims of a commercial harvest that started with czarist Russia's colonisation of Alaska. A 1911 treaty ended the commercial hunt and numbers rebounded.

But the population of sea otters from Kodiak, Alaska, to the western Aleutian Islands has dropped sharply in recent years, declining as much as 67% since the mid-1980s, according to the US Fish and Wildlife Service.

In 2005, the western Alaska otter population was listed as threatened under the Endangered Species Act, with the steepest population drop in the state's Aleutian Islands.

Estes said many scientists studying Alaska's sea otters believe predation by killer whales is the main reason for the recent decline. Whales have increasingly preyed on otters as Steller sea lions and seals have become scarce, Estes said.

The 1989 Exxon Valdez oil spill also killed thousands of sea otters, up to 40% of the population in western Prince William Sound, according to state and federal scientists. The otter population has not fully recovered in spill-affected areas, scientists say.

Read more on:    climate change  |  marine life
NEXT ON NEWS24X

SHARE:

Read News24’s Comments Policy

24.com publishes all comments posted on articles provided that they adhere to our Comments Policy. Should you wish to report a comment for editorial review, please do so by clicking the 'Report Comment' button to the right of each comment.

Comment on this story
0 comments
Add your comment
Comment 0 characters remaining
 

Inside News24

 
/Fashion
 
Traffic
Lottery
 
  • Friday Cape Town - 16:15 PM
    Road name: Wet Weather
    RAIN across the greater Cape Town area - drive with care and use headlights - Allow Extra Tavel Time
  • Friday Kuils River - 09:28 AM
    Road name: Polkadraai Road Eastbound
    ROADWORKS between the R102 Van Riebeeck Road and the R310 Baden Powell Drive exit - DELAYS
 
More traffic reports...
 

Jobs in Cape Town [change area]

Jobs in Western Cape region

Stock Auditor

Cape Winelands
Vine Recruitment

Senior Audit Clerk

Cape Town Northern Suburbs
Hi-Tech Recruitment Cpt
R10 000 - R20 000 Per Month

Audit Manager

Western Cape
SET Recruitment Consultants
R450 000 - R550 000 Per Year

Property [change area]

Travel - Look, Book, Go!

Magical Massinga

Spend 5 nights at the gorgeous Massinga Beach Lodge in Mozambique and only pay for 4 from R13 220 per person sharing. Includes return flights, accommodation, transfers and romantic turndown. Book now!

Kalahari.com - shop online today

2 TV Series for R250

Get 2 TV Series box sets for R250 and save up to R148! Offer valid while stocks last. Shop now!

Mind blowing deals on beauty & fragrances

Save up to 30% off beauty and fragrances. Offer valid while stocks last. Shop now!

Up to 50% off hair care products!

Save up to 50% on professional hair care products at kalahari.com. Offer valid while stocks last. Shop now!

30% off academic books

Score a mind blowing 30% off academic books! Offer valid while stocks last. Shop now!

Mind blowing deals on electronics!

Save up to 35% on electronics. Offer valid while stocks last. Shop now!

OLX Free Classifieds [change area]

Samsung Galaxy s4

Mobile, Cell Phones in South Africa, Western Cape, Cape Town. Date October 24

Best bargain in big bay

Real Estate, Houses - Apartments for Sale in South Africa, Western Cape, Cape Town. Date October 25

VW Golf 6, 1.6 Trendline (Excellent condition)

Vehicles, Cars in South Africa, Western Cape, Cape Town. Date October 25

Nokia N9

The Nokia N9 has a beautiful one-piece, unibody design where...

From R2899.00

I'm shopping for:

Horoscopes
Aquarius
Aquarius

The day may have a fluctuating sensitive energy to begin with, but later when the Moon moves into dramatic and creative Leo you...read more

There are new stories on the homepage. Click here to see them.
 
English
Afrikaans
isiZulu

Hello 

Create Profile

Creating your profile will enable you to submit photos and stories to get published on News24.


Please provide a username for your profile page:

This username must be unique, cannot be edited and will be used in the URL to your profile page across the entire 24.com network.

Settings

Location Settings

News24 allows you to edit the display of certain components based on a location. If you wish to personalise the page based on your preferences, please select a location for each component and click "Submit" in order for the changes to take affect.








Facebook Sign-In

Hi News addict,

Join the News24 Community to be involved in breaking the news.

Log in with Facebook to comment and personalise news, weather and listings.