I may have mentioned before that squid fishermen of the Falkland Islands go after two very different species: Illex argentinus, the shortfin squid, an open-ocean animal that migrates between Falkland and Argentinian waters, and Loligo gahi, the Patagonian squid, which is present in both Falkland and Argentinian waters but doesn't move much between the two.

As a result of these mobile versus sedentary habits, the two squid have different management needs. Since the Illex resource is shared between two nations, decisions made by one necessarily affect the other. It would make sense for them to share management, but that doesn't seem to be working out too well. FIS reports:
While the South Atlantic Fisheries Commission (SAFC), established in 1989, was a forum for joint stock assessments and data exchange between Argentina and the Falklands, Argentina left in 2005 because sovereignty of the Islands was not being placed on the agenda.
On the other hand, Loligo squid in the Falklands don't have much relation to Loligo squid in Argentina, and consequently there's no great need for cooperative management. And unlike the at-times beleaguered Illex fishery, Loligo is doing just fine. In fact, 2012 was a bumper year.

However, there might be something going on in addition to management differences. These two species probably compete with each other (and perhaps even prey on each other), which means that if one is doing well, it can really hammer the other. Taking this into account requires an even more delicate dance on the part of fishery managers . . .