Subscribe free to our newsletters via your
. 24/7 Space News .




ICE WORLD
Warming Antarctic seas likely to impact on krill habitats
by Staff Writers
London, UK (SPX) Aug 23, 2013


In the early life stages krill require deep water with low acidity and a narrow range of temperatures for their eggs to successfully hatch and develop. The larvae then feed on algae on the underside of sea ice.

Antarctic krill are usually less than 6 cm in length but their size belies the major role they play in sustaining much of the life in the Southern Ocean. They are the primary food source for many species of whales, seals, penguins and fish.

Krill are known to be sensitive to sea temperature, especially in the areas where they grow as adults. This has prompted scientists to try to understand how they might respond to the effects of further climate change.

Using statistical models, a team of researchers from the British Antarctic Survey and Plymouth Marine Laboratory assessed the likely impact of projected temperature increases on the Weddell Sea, Scotia Sea and Southern Drake Passage, which is known for its abundance of krill. This region has experienced sea surface warming of as much as 1C over fifty years. Projections suggest this could rise by another 1C by the end of the 21st century.

The models are based on equations which link krill growth, sea surface temperature, and food availability. An analysis of the results, published this week in the online journal PLOS ONE, suggests warming, if continued, could reduce the area of growth habitat by up to 20%.

In the early life stages krill require deep water with low acidity and a narrow range of temperatures for their eggs to successfully hatch and develop. The larvae then feed on algae on the underside of sea ice.

The adults require suitable temperatures and enough of the right type of food (larger phytoplankton) to successfully grow and reproduce. Many of these critical environmental features (temperature, acidity, sea ice and food availability) could be affected by climate change.

The projected effects of warming are not evenly spread. The island of South Georgia is located within the area likely to be worst affected. Here the reduction in krill habitat could be as much as 55%.

The island is home to a range of animals such as fur seals and macaroni penguins that depend upon krill, and others, such as black-browed albatrosses, which eat substantial amounts of krill as well as fish and squid. The researchers say animals which don't travel far to forage, such as fur seals, would be most affected by the projected changes.

Krill is also being commercially fished, although there is nothing to suggest current levels are unsustainable. In fact, at less than 1% of estimated biomass, catches are much lower than most other commercial fisheries.

But the Antarctic krill fishery took 68% of its total catch between 1980 and 2011 from the area of projected habitat degradation. The scientists suggest improved management systems to ensure the fisheries take into account both growing demand for catches and climate change.

Lead author, Dr. Simeon Hill, a marine biologist at BAS, said:

"Each year, growth of Antarctic krill in the Southern Ocean produces new material that weighs twice as much as all the sugar produced in the world. Krill grow fastest in cold water and any warming can slow down or stop growth, reducing the food available for wildlife. Our research suggests that expected warming this century could severely reduce the area in which krill can successfully grow."

Although there is evidence that warming seas pose a threat to Antarctic krill habitats the team of researchers believe this can be mitigated with effective fisheries management systems in place.

.


Related Links
British Antarctic Survey
Beyond the Ice Age






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle








ICE WORLD
Change of Venue for NASA's IceBridge Antarctic Operations
Greenbelt MD (SPX) Aug 26, 2013
This fall, NASA's Operation IceBridge will base its annual Antarctic campaign out of National Science Foundation's McMurdo Station, a change from the mission's previous four campaigns that were based in Punta Arenas, Chile. By switching bases of operations, IceBridge will be able to expand its reach by measuring parts of Antarctica previously unavailable to the mission. "Antarctica is a bi ... read more


ICE WORLD
NASA Prepares for First Virginia Coast Launch to Moon

NASA Selects Launch Services Contract for OSIRIS-REx Mission

Environmental Controls Move Beyond Earth

Bad night's sleep? The moon could be to blame

ICE WORLD
International Space Agencies Outline Steps to Take Humans to Mars

Snapping Pictures of the Martian Moons

Mars Rover Opportunity Working at Edge of 'Solander'

MRO Swapping Motion-Sensing Units

ICE WORLD
NSBRI and NASA Reduce Space Radiation Risks by Soliciting for Center of Space Radiation Research

Next Generation of Explorers Takes the Stage

Has Voyager 1 Left The Solar System?

Groundbreaking space exploration research at UH

ICE WORLD
China launches three experimental satellites

Medical quarantine over for Shenzhou-10 astronauts

China's astronauts ready for longer missions

Chinese probe reaches record height in space travel

ICE WORLD
Cosmonauts Complete Spacewalk, Unfold Russian Flag in Space

Italian astronaut recounts spacewalk drowning terror

ISS Boosting Biological Research in Orbit

Japanese Cargo Craft Captured, Berthed to ISS

ICE WORLD
NASA Explores New Uses for Historic Launch Structures

Telemetry data confirms launch of South Korean satellite

ISRO pins hopes on GSLV-D5

Lockheed Martin Selects CubeSat Integrators for Athena to Enhance Launch Systems Integration

ICE WORLD
Waking up to a new year

Study: Planets might be 'born free' without a parent star

Distant planet sets speed record by orbiting its star every 8.5 hours

Kepler planet hunter spacecraft is beyond repair: NASA

ICE WORLD
Lab-made complexes are "sun sponges"

Physicists pinpoint key property of material that both conducts and insulates

Using x-ray vision to detect unseen gold

U.S. firm releases $1,400 scanner to create 3-D printing files




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement