In Australia -
http://www.theaustralian.com.au/higher-education/dead-zones-found-far-out-to-sea/news-story/d2ce896129f75af1cbf70c68312d9162
Dead zones are common in shallow waters where fertilisers and other chemicals trigger algal blooms. They line the coasts of the US, Western Europe and Japan, and there are about 10 known dead zones around Australia’s southern states.
http://www.abc.net.au/news/2010-11-30/scientists-fear-mass-extinction-as-oceans-choke/2357322
Professor Hoegh-Guldberg says the problem is not as significant in Australia as other parts of the world, but that it is heading along the same, destructive path.
"We've been altering coastal areas, delivering nutrients into the ocean, and of course you see the Great Barrier Reef, which has been quite damaged due to nutrient run-off," he said.
"But the point is that our activities on land have a big influence on what goes on in the oceans and now we are starting to reap the harvest of those changes."
He says the heart and lungs of the planet are being tampered with.
"We are starting to see changes in the ocean's ability to produce oxygen and to produce food and produce all of the ecosystem's services that are so important to not only us, but all of the other organisms on the planet," he said.
"It's mucking around with the heart and lungs of the planet - that's essentially what the oceans are, a huge respiratory system.
and the question, "Can a Vegan Lifestyle Help to Get Rid of Ocean Dead Zones? "
http://www.vivalavegan.net/list/3-articles/457-can-a-vegan-lifestyle-help-to-get-rid-of-ocean-dead-zones.html 
