FAO published some numbers on fishing today:
Global marine catches have been stagnant for over a decade, hovering at around 85 million tons per year. Meanwhile fisheries productivity — measured in terms of catch per fisher, or per fishing vessel — has declined, even though fishing technology has advanced and fishing effort increased.
Naturally, with a global resource that nobody owns or regulates, everybody is trying to exploit it before others can, leading to its decline and reduced benefit for all. Actually, it’s even worse than a grab free for all – governments subsidize vast overfishing fleets.
This is a game theoretical problem. If people can’t do agreements or there can’t be any agreed regulation, the situation leads, perhaps not to the last fish being caught, but at least to the state of fisheries being kept so low that fishing is very barely profitable.
A local optimum (everybody fishes for themselves as much as they can) is very far from the global optimum (total fish catch is increased and it is easier to fish since there are more fish when everybody limits the amount they fish), but the lack of coordination prevents from reaching the global optimum.
This nicely and sadly illustrates how things like contracts, agreements, treaties or regulations could improve the situation for everyone involved.
Of course from one fisherman’s viewpoint, it’s not his fault that everyone is fishing, and any regulations would only hurt him (in the short term they would).
In the past many such things were not a matter of much attention. Technology was so primitive that one could not overfish the seas. Or in other, smaller places where the limits of exploitation could be reached, nations controlled their resources wholly, meaning they could enforce regulation by themselves. It is mostly in the twentieth century that the effects of human action have been so vast that there have been needs for international regulation.
It would be interesting to hear how a libertarian takes these things into account. In my view “everybody for themselves” is a good strategy for many problems, but too simplistic to be used for everything. We see now where it has lead with global fishing.
Central control has also resulted in vast environmental damages, and hurting people as well. The Aral sea is one example.
Hence one would need some kind of negotiations between all the effecting and effected parties, and science and justness based decision making to manage the global fisheries. It is a very hard problem, not technically (you just fish less, nothing could be easier!), but politically.
At the same time, it is a test for humanity. Can this 6 billion bunch of apes engage in decision making that results in the medium term in positive results for all, even though it can be bad for some persons in the short time (though they can be compensated). On this finite size planet, as our capabilities grow, more and more actions are having longer term effects on the whole system. That means the future of both the actor as well as others.