October 28, 2010

 

Canadian scientists devise aquaculture sustainability measures

Researchers in Canada on Wednesday (Oct 27) released the first scientific index designed to measure the impact of fish farming on the environment.

 

Aquaculture has become increasingly controversial because of fears it can harm the environment and use up too many resources.

 

Until now however, there has been no clear way to measure the environmental impact of the practice, said researcher John Volpe from the University of Victoria.

 

Volpe said his "Global Aquaculture Performance Index" - developed with help from the US-based Pew Environmental Group and funding from the American Lenfest Foundation - is intended for use by "industry, farmers, bureaucrats, government ministers and other decision makers."

 

The tool is similar to the "ecological footprint" concept used around the world to assess the overall impact of humans on the environment.

 

Salmon farming in ocean pens already is controversial in North America because of concerns that farmed salmon spreads parasitic lice among already-threatened populations of wild salmon. But the index ranked other species of farmed fish as much worse, said Volpe.

 

"Nearly anything coming out of Asia is problematic," he said, because of unregulated use of antibiotics, spread of parasites, and a greater use of wild species caught without regulations.

 

"Some aquaculture production systems enable and facilitate unsustainable fisheries practices," he said, noting aquaculture has boomed in China especially over the past five years.

 

The index measures the impact of fish farms according to 10 factors. These include the impact on the environment of capturing fish in the wild; the use of cleaning chemicals and antibiotics; the economic damage incurred when farmed fish escape into the wild; energy costs; and the impact on water oxygen levels.

 

Volpe noted that sustainable foods are increasingly popular, as "eat local" and "slow food" movements flourishing in most developed countries.

 

"Measuring the sustainability of seafood is more complex than terrestrial agriculture. You're dealing with the most international, globalised foodstuff that humans consume," he added.