Does America need a 'No Fish Left Behind Act'?
Fishing Quotas
Mankind's appetite has become so voracious that we have wiped out some very numerous species, such as the passenger pigeon, and nearly wiped out others, such as some species of whales. The International Whaling Commission is currently meeting to decide whether to allow any more whales to be caught. Stocks of some kinds of fish have plummeted in recent years, making it necessary for fishing to be regulated too. For example, the Canadian cod fishery collapsed in the late 1980s, and has still not recovered.
The reasons for fish stock collapses can vary - overfishing is not entirely to blame. For instance, barriers or pollution in rivers can prevent fish such as salmon spawning. The mangroves or coral reefs which act as nurseries for fish may have been destroyed. Something may have reduced the fish's food. But for those fish which we fish commercially, overfishing will often be a factor.
Once overfishing has been shown or suspected to be a factor, a common response is to impose quotas. Quotas limit the number of fish that can be caught in a year. Scientists estimate how many of a particular kind of fish there are (perhaps in a particular sea), and then calculate the maximum sustainable yield (MSY). It is a long term average, and is estimated as anything between one third and 80% of the population of mature fish. To take any more would be to seriously restrict the species' ability to replenish itself.
Determining and then enforcing the MSY can be problematic. It is difficult to estimate total populations of fish species. They may be inferred by looking at the number of fish caught and the amount of effort (e.g. days or boat hours) and assuming that the more effort it takes to catch a given weight of fish, the more the fish has been overfished. But declining yields can be due to other factors (e.g. changes in water temperature, variability in ocean currents). Also, it relies on the fishermen reporting their catches accurately, and there being no poachers. Policing the fisherman is nigh on impossible, as the Australians have found with Patagonian Toothfish poachers. Canada has also had trouble with fishing boats from Greenland and the Faroe Islands.
Even after the scientists have come up with a figure for the MSY, that is only the start. Governments and communities rely on their fishing industries, and so are very reluctant to accept a quota which would put their fishermen out of work. This happened to Canada in the 1980s. The cod quota was set considerably above the MSY and the cod fishery completely collapsed, ending a way of life and costing Canada one billion Canadian dollars. The Canadian cod fishery has still not recovered.
When overfishing occurs, the oldest, largest fish tend to be caught first and then, in order for the fishermen to achieve their targets, more and more smaller fish. This means that there are very few fish left capable of breeding, so even if fishing stops, the population is not able to rebound quickly.
The European Union is on the horns of the same dilemma in the North Sea cod fishery, and has compromised. Time will tell.
Recent news stories involving fishing quotas include:
Ocean Conservancy Scorecard Released
The Ocean Conservancy's scorecard rates fish stock management around the United States. The West Coast generally did best but the South and East coasts experienced overfishing. Several kinds of fish are depleted but others have rebounded.
In the same news wire: a species of fungus new to Oregon has been discovered on the southern Oregon coast. There are fears that it may be a threat to Oregon's commercial blackberry crop. It is probably a strain used as a biological control agent in Australia, Chile, and New Zealand.
Please see the following message for the remaining stories. Sue [sysop in NewsForum, World Issues, All Animals forums] | 
