Warming seas pushing marine life to the poles

A NASA image from December 2010 shows a large annual spring-time bloom in waters around New Zealand's Chatham Islands, which teem with life.


Experts had expected the migratory shift of marine life due to warming seas to be slower than that of land species, but they said the opposite is happening.

Warming seas are forcing marine life to shift toward the poles in search of cooler water at an alarming rate, according to a new study.

Breeding and feeding patterns are also changing, "potentially triggering a range of cascading effects" and a "reconfiguration of marine ecosystems" in the not too distant future, the researchers reported in the latest edition of Nature Climate Change.

The experts had expected the migratory shift to be slower than that of land species, but they said the opposite is happening.

Related: Climate change threatens food supply

The marine species most impacted are moving toward the north or south poles at an average of 45 miles per decade, "considerably faster than terrestrial species, which are moving poleward" at about 4 miles per decade, study co-author Elvira Poloczanska said in a statement.

"This is occurring even though sea surface temperatures are warming three times slower than land temperatures," added Poloczanska, a researcher with Australia's national science agency.

"We expected to see more rapid response on land than in the ocean" because the air is warming faster than the seas, study co-author Christopher Brown, a researcher at Australia's University of Queensland, told The Guardian of London.

The faster ocean shift might be because marine animals are able to move vast distances, Brown said, or it could be that land species can adapt by moving shorter distances since they can find cooler temperatures by migrating up or down hills and valleys.

Related: Tempers might rise with temperatures thanks to climate change

The scientists, from 17 institutions around the world, studied a database tracking 1,735 changes in marine life over a 40-year average. They found that 81 percent of those changes were in a direction consistent with warming temperatures. In addition, events tied to spring were happening some four days earlier – nearly twice the figure for land, they reported.

"One of the unique things about this study is that we've looked at everything," Brown said. "We covered every link in the food chain and we found there were changes in marine life that were consistent with climate change across all the world's oceans."

"Some species like barnacles and lots of shellfish are constrained to living on the coast," he added. "If they're already at the edge of the range there's nowhere for them to go. You could potentially lose those."

 

© 2013 Microsoft

http://news.msn.com/science-technology/warming-seas-pushing-marine-life-to-the-poles