Sustainable Sushi – What’s the problem?
We all want future generations to live on an earth like we have, with ocean ecosystems similar to what we enjoy. Some of the current fishing and fish farming operations are depleting fish stocks to dangerously low levels, destroying habitat on a massive scale and polluting the oceans. Changing behaviors is the key to ensuring we have a maintainable situation.
Many fisheries are managed carefully, but anecdotal evidence suggests most are in decline. Fish farming has created huge new problems, as we’ll explore in the next installment. But overfishing is not the only reason marine populations are in decline.
Habitat destruction is another problem. It’s partially due to pollution, but the primary concern here is fishing methods. Harvesting the marine life that lives on the ocean bottom is often done by dragging heavy objects along the bottom. This destructive process eliminates large tracts of natural habitat. Just as ever-increasing economic pressures to convert forest lands into agricultural areas destroys habitat for land animals, tearing up the ocean bottom impacts creatures that live there. It’s difficult to determine how bad the situation is though, because many creatures like octopus are skilled at hiding in small crevices and cracks in that terrain.
The other main problem is depletion of many species populations, largely due to the use of certain fishing techniques. Massive fishing operations often deploy huge nets catching everything large enough to be caught. The enormous “by-catch” resulting from these sloppy mass-fishing techniques is discarded. Yellowfin tuna are often caught using “longline” fishing, which ends up with the demise of large numbers of sharks and turtles and other “by-catch”. But for some species like the Atlantic bluefin tuna, the fishing techniques don’t really matter because they’re so overfished they’re facing possible extinction in the next few years if things don’t change dramatically.
Make no mistake about it though, there are many individual issues contributing to the main problem. There are the cultural issues for example, such as a insatiable Chinese appetite for shark fins which leads to the destruction of millions of sharks each year, many of which have their fins cut off then are tossed overboard to drown. Another examples of this is the Japanese whaling tradition, which continues despite dwindling populations.
So although the details can be complicated, the basic problem is easily understood. Technology has enabled us to become so efficient at harvesting the oceans’ bounty that we have become the primary threat to their sustainability.