>
 
> FishingBoating-World.com
 
 
News Home Newsletters Powerboat-World Australian Cruising World Cruising MarineBusiness-World Animated Knots Video Gallery
MarineBusiness-World Photo Gallery
Sail-World.com : New study casts doubt on Antarctica crab claims
New study casts doubt on Antarctica crab claims


'King Crab on yhe sea bed'    Julian Gutt

A new study has cast doubt on the belief that crabs may have vanished from Antarctica only to return due to warming seas.

The theory surfaced two years ago following the discovery of a major colony of King crabs (Lithodidae) in the Palmer Deep, a basin in the continental shelf off the Antarctic Peninsula. It was thought the species may have left the continent between 40 and 15 million years ago and was returning as seawater temperatures rose. Fears were expressed that its reintroduction would decimate other fauna in the region.

But an extensive study of all known crab records by a team of scientists at British Antarctic Survey (BAS) has led it to conclude the crabs may have been there all along rather than moving in from a different area.

Writing in the online journal PLOS ONE the team, led by marine biologist, Huw Griffiths, claims the 'invasion' hypothesis is fundamentally flawed because it relied upon poor fossil records relating to a completely different group of crabs and that sampling of the extant species is far too limited to draw any firm conclusions.

The fossils of deep water crabs are hard to come by because they are susceptible to decay soon after they die. There is no Antarctic fossil record for King crabs with only two such records existing, neither of which originate from Antarctic waters (south of 60°S). Much of Antarctica is covered with ice restricting access to areas where fossils may be found. This means there is a great deal of uncertainty surrounding the history of crab populations in the continent.

King Crab from South Georgia in the BAS aquarium -  Julian Gutt  

The team assembled a database of more than sixteen thousand records of living and fossil crabs to assess the extent of their populations. Fossil data were compiled from all previously published sources as well as the extensive fossil collection at BAS’ offices in Cambridge. All published data for living specimens were examined as well as records from unpublished fisheries’ and scientific reports.

The first record of a crab in Antarctica is of one from the group Brachyura found on the shores of the South Orkney Islands in 1903. To date, 22 species of crab and lobster have been found in the Southern Ocean, 12 of which are King crabs found in Antarctic waters.

The first record of King crabs dates back to 1967 when an individual was recovered close to Scott Island north of the Ross Sea. The lack of data reflects the fact that very little deep water sampling has been done.

The distribution pattern, with two species being found only in Antarctica (including the one reported as invasive) and no records of them being found elsewhere, implies a long and enduring presence in the region. It would suggest they have had more than a few centuries to develop and evolve.

Lead author, Huw Griffiths, from BAS, said: 'These findings are important because, for the first time, we were able to piece together all available information to get a clearer understanding of the diversity and distribution of crabs in Antarctica. Many of these elusive deep-sea animals, previously thought to be invasive, have turned out to be uniquely Antarctic species.'

Recent studies suggested King crabs would pose a serious risk to native fauna. Invertebrates such as molluscs were thought to be most at risk. But the team says there is strong evidence these crabs are mostly foragers and scavengers attracted to carrion.

The team concludes by recommending that a programme of repeated sampling of King crab distributions in Antarctic waters is conducted.

British Antarctic Survey website


by British Antarctic Survey

  

Click on the FB Like link to post this story to your FB wall

http://www.fishingboating-world.com/index.cfm?nid=111605

10:57 AM Fri 5 Jul 2013GMT


Click here for printer friendly version
Click here to send us feedback or comments about this story.







FishingBoating-World





Pontoon Boats are a hit with families and entertainers by Sanctuary Cove International Boat Show,
















Glacier Bay returns to Australia, re-launching at SCIBS by Sanctuary Cove International Boat Show,
















Power to the people at Sanctuary Cove International Boat Show by Sanctuary Cove International Boat Show,






























Humpback Whales - Non Lethal research
VRFish works with fishers on Corio Bay conflict
Changed boating conditions for ski race on Clarence River
VRFish calls for action on Anglesea River
Submit your entry to the BoatUS Angler 'Catch of the Month' contest
Channel 7 stage returns to Sanctuary Cove International Boat Show
Brisbane Tinnie & Tackle Show - this weekend!
Coastal infrastructure and species loss - Climate Change consequences *Feature
rescueME PLB1 – safety assured in one compact, light package *Feature
Japan's Antarctic whaling program harpooned
All Marine Spares hits the boat show trail in a trailer *Feature
Macquarie perch stocked into three northern Victorian waters
Local council celebrates commitment to protect the Great Barrier Reef
Go crazy about whales in a special family fun day at the museum
New generation trawler boats - tradition with a twist
Arvor releases new Sportsfish range
AIMEX focuses on commercial show in Asia
Further Australian growth for Stabicraft
Southport Yacht Club will host a free 'Discover Sailing Day'
Melbourne Boat Show earlier this year - 12 to 16 June
FinScan digital switching fitted to new rescue vessels   
Kids' Zone a drawcard at Brisbane Tinnie & Tackle Show   
Brisbane Tinnie & Tackle welcomes Engel as stage sponsor   
BIAV appoints new GM   
Jet stream gets fish in hot water   
Trash to Treasure - A seafood story   
Big waves shown to be energetically costly for fish   
Fisherman nabbed for illegal fishing at Point Lonsdale   
Maritime Alert - Dangerous conditions forecast for NSW boaters   
World Recreational Fishing Conference - First call for papers open   
12 weeks til Melbourne Boat Show   
First deadline for SCIBS exhibitors looms March 24   
Fishing for Culture - A celebration of fishing in culture   
Improving fish habitat by building a fishing line recycling bin +Video   
Greater numbers of catchable King George whiting in the years to come   
Paul Burt, boating guru, is the face of Sanctuary Cove Boat Show   
Marine Industry loses a loyal servant: Vale Gunter Bruckner   
Positive pass mark for new venue   
Couran Cove signs lease deal with Hope Island Marina   
Phones outpace PCs and TV as preferred device   


For this week's complete news stories select    Last 7 Days
   Search All News
For last month's complete news stories select    Last 30 Days
   Archive News







Sail-World.com  


















Switch Default Region to:

Social Media

Asia

Australia

Canada

Europe

New Zealand

United Kingdom


http://www.sail-world.com/event_images/image/Twitter_logo_small.png http://www.sail-world.com/event_images/image/FaceBook-icon.png  http://www.sail-world.com/event_images/image/RSS-Icon.png

United States

Cruising Northern

Cruising Southern

MarineBusiness World

PowerBoat World

FishingBoating World

 

Contact

Commercial

News

Search

Contact Us

Advertisers Information

Submit news/events

Search Stories/Text

Feedback

Advertisers Directory

Newsletter Archive

Photo Gallery

 

Banner Advertising Details

Newsletter Subscribe

Video Gallery

Policies

 

 

 

Privacy Policy

 

 


Cookie Policy

 

 



This site and its contents are © Copyright TetraMedia and/or the original author, photographer etc. All Rights Reserved.  Photographs are copyright by law.  If you wish to use or buy a photograph contact the photographer directly.
XLXL WAS FBW