If you don't quite have a handle on the scale of overfishing, consider this statement: Scientists say that about one-third of the world's oceans could benefit from a 20-year ban on fishing so that fish stocks can be replenished. Also consider that currently a mere 0.7% of the world's oceans are protected. Yeah, it's a big problem. It's Blue August here on TreeHugger and Planet Green, so a quick look back at some of the most interesting stories which flesh out those stats seems in order:
1. We've Been Overfishing For a Long Time
First up we should set the record straight on thing. Overfishing is not just a modern problem. In fact, humans have been overexploiting the resources in the seas around them for a long time.
Environmental historians from Trinity College Dublin have shown that 1000 years ago in Europe humans had so depleted freshwater fish that they began plying the waves in earnest. 500 years later most of the coastal stocks began declining, so people began deep-sea trawling.
The advent of industrial fishing, combined with increasing demand for fish from ever increasing human populations, may have taken the problem global. But humans have a long history of fishing an area until nothing's left and then moving on -- the trouble is, now, there's nowhere really to move on to.
photo: Kristine via flick
2. Overfishing Changes Ecosystems
When an area is overfished it doesn't mean that there's nothing left in the sea. Oftentimes when you remove one major species -- or even a not-so-major one -- it upsets the balance and things go topsy turvy for a while as new species move in or expand.
One recent example of this are jellyfish taking over. Overfishing is depleting the fish that keep jellyfish populations in balance by eating them or their food and populations are rising.
What's worse is that climate change could make it worse, creating conditions in which jellyfish can thrive, but other animals cannot.
photo: Phillip Capper via flickr
3. Good Fisheries Management is Key to Recovery
That 20-year ban mentioned in the intro is only part of the solution. In the past six months we've seen a number of stories highlighting the importance of good fisheries management. Clearly present quota systems limiting the number of days at sea don't work-- more often than not just creating a mad dash to scoop up as many fish as possible in the shortest period of time.
Catch Share Systems Could Help
One way to correct this is through the use of catch-share systems. NOAA head Jane Lubchenko describes them:
The shares of the fishery are allocated to entities — those might be fishermen, or boats, or communities — and let’s say that fishermen have a guaranteed fraction of the catch that is their privilege to catch every year. So the total amount of fish that can be caught in any year is divided into these fractions. For example you might be allocated 10 percent of the total catch for the year, I might be allocated 5 percent of the total catch for the year. It’s like dividing up a pizza. The way most of them are done there is simply an allocation that is given based on past fishing history, but once you have that allocation, you can trade it, you can sell it. Many fishermen are concerned with the problem of consolidation, where a few people would buy up all the shares. You can structure the rules of fisheries to limit that happening... And the amount that can be caught in any one year is determined scientifically by what is sustainable for that fishery.
The Good News: Better Management Works
Need some proof that better fisheries management can actually help? A recent study shows that in those places which actually think more holistically about fisheries management -- and accept that some short-term pain is required to establish long-term sustainability -- fish stocks are increasing.
Alaska, New Zealand, and Iceland were all held up as exemplars of good management.
The authors pointed out though that there really isn't one best management tool: Whether better community management is needed, a catch share system, fisheries closures, or gear restrictions, all depends on the local circumstances.
But the message remains clear: 63% of the fisheries they examined were in bad shape and needed to be rebuilt.