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

Express 27 National Championship overall + Video by Erik Simonson, Pressure-Drop.US,




















America's Cup: Louis Vuitton Cup's Yves Carcelle dies at 66 *Feature by Richard Gladwell/Sail-World.com/nz,












Audi Melges 20 World Championship - ‘Samba Pa Ti’ crowned champion by International Audi Melges 20 Class Association,










Audi Melges 20 World Championship - Final race to decide champion by International Audi Melges 20 Class Association,










Fort Lauderdale International Boat Show - 13 things to See and do by Fort Lauderdale International Boat Show,




Volvo Ocean Race: Update from Team Vestas Wind in images by Richard Gladwell/Sail-World.com/nz,








Audi Melges 20 World Championship - Classic Garda conditions on day 2 by International Audi Melges 20 Class Association,


PWA Alacati World Cup - Intense competition on day 3
America's Cup: 'The Doc' appointed as Commercial Commissioner
Wake Park Triple Crown - Registration open for final stop
Audi Melges 20 World Championship - Day 2 images by Stefano Gattini
Volvo Ocean Race - Two more join Dongfeng Race Team
OHPRI Teen Summer Camps make a splash
East to West: A profile of Volvo Ocean Race crew Team Dongfeng
Extreme Sailing Series - First-ever Turkish team to race in Istanbul
Audi Melges 20 World Championship - Race 4 images by Max Ranchi
New Around Britain and Ireland Monohull 40ft and less world record
Detroit Cup - Fifth place finish a difficult result for Neptune Racing
Audi Melges 20 World Championship - Alessandro Rombelli's 'STIG' leads
Volvo Ocean Race: Call of Duty comes first for Team Alvimedica
Audi Melges 20 World Championship - Day 1 images by Stefano Gattini
Helping boaters understand weather basics
PWA Alacati World Cup - Exciting finish on day 2
Match 40s find the surface again + Video
Audi Melges 20 World Championship - Day 1 images by Max Ranchi
Clagett Regatta names first Executive Director
Transatlantic Race - Fleet expanded for 2015 edition
IFDS World Championship overall   
Anna Tunnicliffe: Alinghi finishes second - Extreme Sailing Series   
2014 18' Skiff International Regatta - Day 2   
2014 Audi Melges 20 World Championship - It's go time in Garda   
2nd Annual Keith Dinsmoor Regatta September 13-14   
Aldo Alessio Regatta - Three days of tight racing   
PWA Alacati World Cup - First blood to Van Der Steen and Offringa   
Oakcliff Sailing hosts the Nacra 17, 49er and 49erFX Nationals + Video   
International 18ft Skiff Regatta underway on San Francisco Bay   
Maxi Yacht Rolex Cup 2014 - Quality fleet for Maxi Classic   
Sailing Champions League - which is Europe's best sailing club?   
Weta fun at the Wine & Roses Regatta   
Extreme Sailing Series: The Wave, Muscat claims victory on Cardiff Bay   
International 14 World Championships 2015: Not just for boys   
Rio de Janeiro achieves 50% treatment of sewage outflow *Feature   
2014 AWT Quatro Desert Showdown - Event memorable videos   
2014 18' Skiff Int Regatta: Day 1 at San Francisco - Reversal on beach   
Emirates Team NZ: Last race boost cannot save team from table bottom   
PWA Alacati World Cup - Furious slalom is upon us   
J/111 World Championships - The Winner is Shmokin Joe!   


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 VIR US
LocalAds   DE  ES  FR  IT