A few years ago at the Double Musky Inn in Girdwood, Alaska, I had a halibut dinner so delicious, I can still taste that fish. Good restaurant? Yes, but even better fishery management. About a decade ago, the Alaskan halibut catch was switched from a system of “catch all you can” in a very short period, to a system of tradeable permits. Now halibut season does not happen over a few chaotic days marred by colliding boats and overlapping lines, followed by freezing of the fish and a price bust as everything hits the market at once. Instead, fishermen holding an assured right, which they won on the free market (to bid for a permit, go to www.alaskabroker.com), spread their work over many months. Thus halibut coming to the market are just-caught fresh, and the price of fish is less likely to soar and plunge. And halibut stocks, spared a concentrated onslaught of fishing boats, are more sustainable.

Many environmental alarms are overstated, but fishery depletion is not. Numerous fish stocks are shrinking; in 2003, about a third were close to collapse. Because developing nations depend on fish for protein, this issue is not just for sushi aficionados. Generally, nations control the waters out to 200 miles off their coastlines. Some use cumbersome top-heavy regulations to limit fishing in their coastal waters, and the results aren’t encouraging. In some places, like Maine’s lobster fishery, fishermen often self-regulate. But increasingly, nations are turning to tradeable permits, which go by names such as Dedicated Access Privilege or Individual Transferable Quotas. Australia, New Zealand, and Iceland pioneered the idea in the 1980s, and their fish stocks have for the most part recovered nicely; a recent University of California study shows that privatizing fishing rights usually makes fish populations significantly less prone to collapse.

Unfortunately, only limited laws govern the open ocean, where factory trawlers scoop up huge volumes of fish without concern for maintaining a healthy population. These waters epitomize the “tragedy of the commons,” in which “anything goes” leads to runaway exploitation, because no one has a property interest in safeguarding the common resource. The Law of the Sea Treaty, written before the development of tradeable quotas, could be amended to apply the idea to blue water, or open ocean, beyond the 200-mile mark. Some will oppose this as converting what’s under the seas into private possession, but the alternative seems to be catastrophic overfishing until the ocean biosphere collapses. An international system of tradeable open-seas fishing permits wouldn’t be easy to enforce at first (enforcement of many international agreements gets worked out with experience). Here is the carrot at the end of the fishing line: because fish lay fantastic quantities of eggs, when fish-stock depletion stops, the population recovers quickly, meaning more fish for everyone.