Welcome to FIS   Sponsored By
Subscribe to FIS | Register with FIS | Advertise with FIS | Newsletter | About FIS | Contact us
   


Marine biologist Dag L Aksnes. (Photo: FIS Stock)

Climate change darkens water, drives fish away

Click on the flag for more information about Norway NORWAY
Tuesday, November 20, 2012, 04:40 (GMT + 9)

Norwegian coastal waters are darkening due to changes in weather and climate, damaging optical conditions for marine animals.

Marine biologist Dag L Aksnes of the University of Bergen has analysed the impacts of these declining optical conditions with some funding from the Research Council of Norway's research programme on the Oceans and Coastal Areas (HAVKYST). He explained that this occurs when coloured matter from rivers and lakes flows into the sea and mixes with salt water.

"This fresh water contains far more coloured dissolved organic matter (CDOM) than marine water, so our coastal waters are darkening," explains Aksnes, the Research Cuncil reports.

Aksnes and his colleagues have been studying the Lurefjorden and Masfjorden fjords in northern Hordaland county on Norway's western coast for many years.

While the fjords are similar and close to each other, Masfjorden contains far more seawater than Lurefjorden, which contains lower-salinity coastal water all the way down to its seabed. Although Masfjorden still has an ecosystem dominated by fish, the darker Lurefjorden has a greater abundance of the jellyfish Periphylla periphylla.

"Periphylla periphylla is a very light-sensitive jellyfish that thrives best in the world's very deep marine waters," continued Aksnes. "But the water in Lurefjorden has now become so murky and dark that it is probably helping this jellyfish to thrive. At the same time, the fjord has become less hospitable as a habitat for important fish species."

Visibility conditions at Lurefjorden have made it more difficult for fish to find their prey, but not for the blind jellyfish. The jellyfish now have virtually no competition for the abundant prey organisms, Aksnes elaborated.

He highlighted that there is a clear correlation between poorer conditions for fish, the increase in jellyfish and the lasting changes in light conditions in the country’s coastal waters.

These conditions also affect algal photosynthesis and the production of organic compounds – which is why the researchers believe that light conditions impact most organisms.

The project demonstrates that changes normally linked to eutrophication (nutrient pollution) and human emissions of nutrients can also cause the water to become darker, reducing the abundance of attached algae such as seaweed and kelp while fueling the growth of planktonic algae.

Meanwhile, nutrient concentration climbs and oxygen saturation in the marine layers falls.

"More precipitation means that more murky fresh water mixes with the coastal water, making it less saline and murkier," explained Aksnes.

"Furthermore, studies done at the University of Oslo indicate that increased precipitation and rising temperatures lead to changes in vegetation on land, which in turn increases the concentration of CDOM in the fresh water that mixes with the coastal water. We don't know yet whether this leads to undesired changes in our coastal ecosystems, but if so, it will be hard to reverse," the professor added.

By Natalia Real
[email protected]
www.fis.com


 Print


Click to know how to advertise in FIS
MORE NEWS
Russian Federation
Apr 21, 02:50 (GMT + 9):
Russian Fishery to set up pollock processing plant in the Russian Far East
Australia
Apr 21, 02:30 (GMT + 9):
South Australian sardine fishery to enter MSC assessment process
Worldwide
Apr 21, 02:00 (GMT + 9):
IN BRIEF - Small changes in rainforests cause big damage to fish ecosystems
Australia
Apr 21, 02:00 (GMT + 9):
Salmon cannery hopes to attract Australian consumers’ interest
Portugal
Apr 21, 01:50 (GMT + 9):
New tuna factory to start operations in Vila Nova de Cerveira
United Kingdom
Apr 21, 01:30 (GMT + 9):
The British encouraged to consume jellyfish
Canada
Apr 21, 01:00 (GMT + 9):
IN BRIEF - BC oyster farmers taking big hit as three farms still closed due to contamination
United Kingdom
Apr 21, 01:00 (GMT + 9):
IN BRIEF - Salmon packs recalled over health concern
Senegal
Apr 21, 01:00 (GMT + 9):
IN BRIEF - A rise in foreign industrial trawlers off the coast of Senegal is causing local fishermen to lose their livelihoods
United States
Apr 21, 01:00 (GMT + 9):
IN BRIEF - Local Shellfish Beds Restricted Due To Pollution
Worldwide
Apr 21, 01:00 (GMT + 9):
IN BRIEF - Annual 5.0% Growth expected for Global Aquaculture Market by 2021
Peru
Apr 21, 00:00 (GMT + 9):
Virtual platform to favour data sharing on fight against IUU fishing
United States
Apr 20, 23:20 (GMT + 9):
Five Alaska seafood businesses to participate in trade mission to China
European Union
Apr 20, 22:50 (GMT + 9):
International high-tech system project could revolutionise fishing industry
Spain
Apr 20, 22:30 (GMT + 9):
Alantra fund acquires Canarian fish producer and distributor



Lenguaje
FEATURED EVENTS
  
TOP STORIES
Russian Fishery to set up pollock processing plant in the Russian Far East
Russia Fed. The Russian Fishery Company has announced plans to start setting up a fish processing factory at Nadezhdinskaya Priority Development Territory, close to Vladivostok, in the Russian Far East.
Foundation to award USD 950,000 for fisheries innovation projects
United States The National Fish and Wildlife Foundation has made a request for proposals focusing on innovation and supporting effective participation of fishermen and fishing communities in the implementation of sustainable fisheries in the United States.
European Parliament approves EU-Mauritius fisheries agreement
European Union The plenary session of the European Parliament approved the fisheries agreement between the European Union and Mauritius, which will be valid for four years and benefits 85 EU vessels.
EC intends to speed trade deal settlements with with Japan and Singapore
European Union The EC proposes to speed the settlement of the Economic Partnership Agreement with Japan and the trade and investment agreements with Singapore.
 
Maruha Nichiro Corporation
Nichirei Corporation -Headquarter-
Pesquera El Golfo S.A.
Ventisqueros - Productos del Mar Ventisqueros S.A
Wärtsilä Corporation -Wartsila Group Headquarter-
ITOCHU Corporation -Headquarter-
BAADER - Nordischer Maschinenbau Rud. Baader GmbH+Co.KG (Head Office)
Inmarsat plc - Global Headquarters
Marks & Spencer
Tesco PLC (Supermarket) - Headquarters
Sea Harvest Corporation (PTY) Ltd.
I&J - Irvin & Johnson Holding Company (Pty) Ltd.
Blue Continent Products (Pty) Ltd - (Oceana Group Limited)
Pesquera San Jose S.A.
Nutreco N.V. - Head Office
CNFC China National Fisheries Corporation - Group Headquarters
W. van der Zwan & Zn. B.V.
SMMI - Sunderland Marine Mutual Insurance Co., Ltd. - Headquarters
Icicle Seafoods Inc. -Headquarter-
Starkist Seafood Co. - Headquearters
Trident Seafoods Corp.
American Seafoods Group LLC - Head Office
Marel - Group Headquarters
SalMar ASA - Group Headquarters
Sajo Industries Co., Ltd
Hansung Enterprise Co.,Ltd.
BIM - Irish Sea Fisheries Board (An Bord Iascaigh Mhara)
CEFAS - Centre for Environment, Fisheries & Aquaculture Science
COPEINCA ASA - Corporacion Pesquera Inca S.A.C.
Chun Cheng Fishery Enterprise Pte Ltd.
VASEP - Vietnam Association of Seafood Exporters & Producers
Gomes da Costa
Furuno Electric Co., Ltd. (Headquarters)
NISSUI - Nippon Suisan Kaisha, Ltd. - Group Headquarters
FAO -Food and Agriculture Organization- Fisheries and Aquaculture Department (Headquarter)
Hagoromo Foods Co., Ltd.
Koden Electronics Co., Ltd. (Headquarters)
A.P. Møller - Maersk A/S - Headquarters
BVQI - Bureau Veritas Quality International (Head Office)
UPS - United Parcel Service, Inc. - Headquarters
Hamburg Süd Group - (Headquearters)
Armadora Pereira S.A. - Group Headquarters
NOAA - National Oceanic and Atmospheric Administration (Headquarters)
Omega Protein Corporation -Headquarter-
Marona S.A.
Marine Harvest ASA - Headquarters
Marubeni Europe Plc -UK-
Findus Ltd
Icom Inc. (Headquarter)
WWF Centroamerica
Oceana Group Limited
The David and Lucile Packard Foundation
Ajinomoto Co., Inc. - Headquarters
Friosur S.A. - Headquarters
Cargill, Incorporated - Global Headquarters
Benihana Inc.
Leardini Pescados Ltda
Mitsubishi Corporation Marine Products Depts. D.Team
CJ Corporation  - Group Headquarters
Greenpeace International - The Netherlands | Headquarters
David Suzuki Foundation
Fisheries and Oceans Canada -Communications Branch-
Mitsui & Co.,Ltd - Headquarters
NOREBO Group (former Ocean Trawlers Group)
Natori Co., Ltd.
Carrefour Supermarket - Headquarters
FedEx Corporation -Headquarter-
AKBM - Aker BioMarine ASA
Seafood Choices Alliance -Headquarter-
Austevoll Seafood ASA
Walmart / Wal-Mart Stores, Inc. (Supermarket) -Headquarter-
New Japan Radio Co.Ltd (JRC) -Head Office-
Gulfstream JSC
INVE Group - Head Office
Marine Stewardship Council - MSC Worldwide Headquarters
Royal Dutch Shell plc (Headquarter)
Genki Sushi Co.,Ltd -Headquarter-
Iceland Pelagic ehf
AXA Assistance Argentina S.A.
Caterpillar Inc. - Headquarters
Tiger Brands Limited
Morpol ASA - Group Headquarters
SeaChoice
National Geographic Society
AmazonFresh, LLC - AmazonFresh

Copyright 1995 - 2018 Fish Info & Services Co.Ltd| All Rights Reserved.   DISCLAIMER