Written by Peter Terry Friday, 03 November 2006 19:27
.jpeg "inter_fish_image(1).jpeg")
Team member Steve Palumbi of Stanford University says the threat does not just mean that fish could be off the menu for the next generation. The depletion in biodiversity could also turn coastal regions into dangerous places with noxious algae blooms gaining the upper hand.
"Many of the economic activities along our coasts rely on diverse systems and the healthy waters they supply," Mr Palumbi said in a statement released yesterday.
"The ocean is a great recycler. It takes sewage and recycles it into nutrients, it scrubs toxins out of the water, and it produces food and turns carbon dioxide into food and oxygen.
"But in order to provide these services, the ocean needs all its working parts, the millions of plant and animal species that inhabit the sea."
Unfortunately the research team has found that that the biodiversity of the world's oceans is now declining so fast, the sea's ability to produce seafood, resist disease, filter pollutants, and rebound from such stresses as over fishing and climate change, is unravelling fast.
In the latest issue of the international journal, Science, Mr Palumbi and co-author, Boris Worm of Dalhousie University, say on current trends all wild seafoods will be 90% depleted within 45 years and bring about the effective collapse of the global industry.
Their predictions are based on a four-year analysis of existing data on ocean species and ecosystems, and "synthesising historical, experimental, fisheries, and observational datasets" to understand the importance of biodiversity on a global scale.
The study analysed 32 controlled experiments, observational studies from 48 marine protected areas, and global catch data from the UN's Food and Agriculture Organization's (FAO) database of all fish and invertebrates worldwide from 1950 to 2003.
The scientists also looked at a 1000-year time series for 12 coastal regions, drawing on data from archives, fishery records, sediment cores and archaeological data.
"We see an accelerating decline in coastal species over the last 1000 years, resulting in the loss of biological filter capacity, nursery habitats, and healthy fisheries," said another research contributor, Heike Lotze also of Dalhousie University.
Can it be stopped?
According to Mr Worm, it can. "The data show us its not too late. We can turn this around."
The answer he says is to create more marine parks.
"But less than one percent of the global ocean is effectively protected right now," Mr Worm said.
"We won't see complete recovery in one year, but in many cases species come back more quickly than people anticipated — in three to five to ten years. And where this has been done we see immediate economic benefits."
The researchers have concluded that restoring marine biodiversity through an ecosystem based management approach is the only way to reverse the trend.
That will require "integrated fisheries management", pollution control, maintenance of essential habitats and the creation of marine reserves.
They say doing nothing would impose a serious threat to global food security.
The US National Science Foundation and the University of California funded the research.
Subscribe to this comment's feed
