sail-world.com
 
 
News Home Cruising Photo Gallery Video Gallery

 

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.sail-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.


News - USA and the World

The first annual WetaFresh is a big success by Tim Wieringa, Muskegon, MI














Techno 293 Worlds - France and Italy claim titles by International Windsurfing Association,














420 World Championship - Singapore and Spain out front by 420 International Class Association,






























Lightning strikes cut short CFJ Nationals by Andy Kopetzky, Santa Monica Bay








Sevenstar Round Britain and Ireland Race sets off August 10th
PWA Fuerteventura Grand Slam - Antoine Albeau victorious on day 5
Snipe Western Hemisphere and Orient Championship headed for San Diego
WPA Championships - Kids race divisions offered
New Clever Pig launched by US Sailing
America's Cup: Group agrees to co-operate in London Meeting
Copa del Rey Mapfre - Build-up reveals some remarkable enthusiasm
Marblehead NOOD Regatta - Images by Leighton O'Connor
America's Cup: Two AC72 skippers discuss Foiling Moths and the Cup
RS Feva World Championship - Brilliant sailing on day 2
America's Cup: Alameda makes overtures on Venue hosting for San Fran *Feature
Cape Panwa Hotel Phuket Race Week 2014 - Relishing a challenge
Edgartown Race Weekend - BBBR and Round-the-Island Race winners named
Etchells Invitational Cup - Aussies take early lead in Cowes
PWA Fuerteventura Grand Slam - Antoine Albeau strikes back on day 4
Aquece Rio – International Sailing Regatta - All set for test event
ISAF World Sailing Rankings for 28 July 2014
29er World Championship - All set in Kingston
ORC World Championship - Third Course area opens for huge fleet
Day one of the Allen RS Feva World Championships
Anna Tunnicliffe: Final two days of the 2014 Reebok CrossFit Games   
Joachim Aschenbrenner takes gold at ISAF Youth Match Race Worlds 2014   
Maxi Soh scores double wins in CMRC Summer Doubleheader   
29er World Championship opening ceremonies in Confederation Park   
PWA Fuerteventura Grand Slam - Action resumes on day 3   
Land Rover Sydney Gold Coast Yacht Race Start 2014 VIDEO   
Laser Radial Men’s World Championship 2014- Final day   
2014 Pacific Cup - Scarlet Runner wins   
Gladwell's Line: America's Cup - Joint Statement is a curious note *Feature   
ISAF Youth Match Racing World Champ - Top four battle it out for final   
BIC Techno 293 Worlds 2014 - Day 6   
PWA Fuerteventura Grand Slam - Wind teases competitors on day 2   
Women’s Match Race Golfe du Morbihan - Action-packed day of racing   
Herreshoff Marine Museum announces successful fundraising campaign   
Brewin Dolphin Commodores' Cup - The most comprehensive victory yet   
Anna Tunnicliffe fourth at mid-point of 2014 Reebok CrossFit Games   
2014 29er North American Open Championship - Australians win   
INSA Sabot II Invitational Regatta - Erik Hou claims victory   
CMRC Summer Invitational Series - Maxi Soh wins Doubleheader A event   
International Moth World Championships - Nathan Outteridge wins   


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 US
LocalAds   DE  ES  FR  IT