> Powerboat-World.com
 
 
News Home Video Gallery Newsletters FishingBoating Features Photo Gallery Sail-World Australia Australian Cruising
MarineBusiness-World

 

Sail-World.com : New research shows how much food is needed by seabirds

New research shows how much food is needed by seabirds

'Krill - Euphausia superba. The catch of a net land off South Georgia: Antarctic Krill, Euphausia superba.'    British Antarctic Survey ©

It has been shown by an international group of scientists that numerous seabirds begin to suffer when the available food in the ocean declines beneath a critical level. The level is about one-third of the maximum measured amount of food available.

They have found that this critical level is about the same for seabird species around the world. Their study — the most comprehensive ever undertaken — covers birds from the Arctic to the Antarctic and from the Pacific to the Atlantic.

The study focussed upon seabirds near the top of the food chain that feed mainly on fish like sardines, anchovies and sand eels and, in the Antarctic, on krill (small, shrimp-like crustaceans). These seabirds are often key species in marine ecosystems that are sometimes also exploited by fishers, but exploitation of species on which they feed can put them at risk.

Dr Ian Boyd of the Scottish Ocean Institute, University of St Andrews, who co-led the study, said, 'When combined with the effects of climate change, we need to develop better methods of setting the limits of exploitation of important marine species.

Brown skua and Adelie penguins. Basically fish-eaters brown skuas are also predators and scavengers. -  British Antarctic Survey?nid=92568 ©  
This means being able to establish general guidelines that, if exceeded, will cause changes to other important components in the ecosystems. Seabirds are some of the best and most easily measured indicators we have of the health of these ecosystems and it seems sensible to use them in this context'.

The researchers used data collected from fourteen species including penguins, terns, skuas and a species of gull. Their success at producing chicks was measured by counting the number of nests and the resulting chicks, yielding an estimate for the average number of chicks produced per nest. This was related to annual estimates of the abundance of that species’ prey based on counts or, in the case of krill, on the reflection of sound waves emitted from research ships.

Observation periods of between 15 and 47 years yielded an overall total of 438 years of observations, which constitutes one of the most comprehensive global databases ever assembled for predators and their prey.

The effect of low prey abundance was similar in all regions of the world. When the amount of fish in the sea was greater than one-third of the maximum ever recorded, the number of chicks produced was unaffected by changes in food availability. But if the fish abundance fell below this one-third threshold then breeding success declined.

Leader of the team, Dr Philippe Cury of the French Research Institute for Development (IRD) said, 'We were amazed by the consistency of the relationship around the globe. This suggests that we have found an important benchmark that could be used as a guide to limit the amount of fish taken from the sea in order to maintain seabird populations in the long term.'

The team were stimulated to undertake their study by growing concerns about the effects that fishing may be having upon some of these important species in marine ecosystems.

Professor Eugene Murphy of British Antarctic Survey and a co-author of the report, said, 'In the Antarctic overall levels of krill fishing are currently low and sustainable. However, the congregation of many predators in concentrated areas for breeding can mean that local krill exploitation may affect the viability of these breeding colonies.'

This study highlights the importance of long-term observations in developing our understanding of complex marine ecosystems.




by British Antarctic Survey

  

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

http://www.powerboat-world.com/index.cfm?nid=92568

12:20 AM Thu 5 Jan 2012 GMT






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


Power Boat News



























Understanding the Ocean's role in Greenland Glacier melt by Woods Hole Oceanographic Institution (WHOI),


Dangerous conditions for boating on entire NSW Coast by Transport Roads and Maritme Services,


Revealing report on Search for American yacht Nina released *Feature by Rob Kothe and the Sail-World team,












AYSS PacificNet/Tahiti voted a success! by Asia Pacific Superyachts,














Dangerous conditions forecast for NSW boaters by Roads and Maritime Services,


APSNZ appoints Duthie Lidgard as new MD by Asia Pacific Superyachts,


Whale freed from rope at Byron Bay by Department of Agriculture, Fisheries and Forestry,






World premieres and national debuts for Sydney International Boat Show
Marine Auctions experiencing rising tide of interest *Feature
Tags reveal Chilean devil rays are among ocean's deepest divers
Auckland On Water Boat Show to hold world record attempt
Zodiac at Sydney International Boat Show 2014 – Australian
Gold Coast International Marine Expo - Exhibitor space filling fast
Ceramic coated exhaust manifolds reduce engine bay temps on superboat
Reminder of safe distance requirements for whales
Changes to Australian bass closed season
Fusion achieves industry-wide acceptance of FUSION-Link
BSE Brisbane Slipways open for business as normal
Honda’s everywhere at Sydney International Boat Show!
Fifth round of XCAT World Powerboat Series moves to China
Sly 43 - Making her Australian premier
Maritimo full of confidence following recent wins
Australia event cements its position as hosting 'the' marina party
Up close and personal with whales on the Gold Coast
SA Marina Day encourages South Australians to enjoy their marinas
Southport Yacht Club raffle: Dusit Thani, BRIG Falcon, Marriott stay
Enjoy the whale spectacle, just keep your distance
The Dinghy Nav Light Solution- a brilliantly dumb idea   
Extension granted for salvage of a paddle steamer on the Murray River   
Sydney International Boat Show set to embrace new location   
Thermal imaging helping bulk carriers avoid collisions in port and in   
Third CYCA Solas Trusts grant to Australian Volunteer Coast Guard   
CruiseCraft adds Explorer 595 Hard Top   
Severe weather warnings prompt reminder to boat owners   
Be won over by the new Azimut 50   
Predictwind unlocks more features on free accounts   
Tammy Wolf and Mercury's Formula 2 Powerboat on to Divisional Champion   
Monaco Yacht Show 2014 - the biggest superyacht show ever   
Biggest Display ever and 18 launches at SIBS   
Gold Coast International Marine Expo helps Sailability grant FREEDOM   
Exhibitors heat up for Cannes Yachting Festival   
Benetti 108 tri-deck Tradition Supreme will launch in Cannes   
St Kitts open for superyacht business   
Marine World Sales: The latest in buying and selling marine online   
UIM XCAT - Massive fight from Fazza secures fourth consecutive title   
Peters & May launch Mediterranean and USA to East Coast Australia   
Lifejackets are imperative: don't rely on sheer luck   


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/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 PBW
LocalAds   DE  ES  FR  IT