Suffocating Dead Zones Spread Across Worldâ€™s Oceans (David Adam)

Created by : Francis Goodwin View profile

Critically low oxygen levels now pose as great a threat to life in the world’s oceans as overfishing and habitat loss, say experts.

(Guardian) -- Man-made pollution is spreading a growing number of suffocating dead zones across the world’s seas with disastrous consequences for marine life, scientists have warned.

The experts say the hundreds of regions of critically low oxygen now affect a combined area the size of New Zealand, and that they pose as great a threat to life in the world’s oceans as overfishing and habitat loss.

The number of such seabed zones - caused when massive algal blooms feeding off pollutants such as fertiliser die and decay - has boomed in the last decade. There were some 405 recorded in coastal waters worldwide in 2007, up from 305 in 1995 and 162 in the 1980s.

Robert Diaz, an oceans expert at the U.S. Virginia Institute of Marine Science, College of William and Mary, at Gloucester Point, said: “Dead zones were once rare. Now they’re commonplace. There are more of them in more places.”