Game theory in the ‘Mackerel Wars’
In the paper titled “Game theory and fish wars: The case of the Northeast Atlantic mackerel fishery”, Jensen et al. study the ‘Mackerel Wars’ that occurred between 2010 and 2014 and apply a mathematical analysis based on game theory on the incident. This fishing dispute between Norway, Iceland, the Faroe Islands, and the EU began when fishers from Iceland and the Faroe islands caught more mackerel than was allowed in the agreed quota amounts. EU countries like Scotland and Ireland along with Norway harshly criticized the move by their northern neighbors while Iceland and the Faroe Islands maintained that the increased catch was made possible by the mass migration of said fish into the Icelandic seas, and that they would continue to fish to fill the quotas they had set for themselves. Jensen et al. used statistical data on the catch amounts of each country’s fishing industries to show the payoffs for each country in the event that they cooperate and fish within the initially set quotas or not cooperate and fish above the quotas.
The example of fishing is brought up regularly in the discussion of game theory and especially of the tragedy of commons. The tragedy of the commons refers to a situation where open access to a resource with little rules on legal rights of use leads to all parties overusing the resource to the point of depleting said resource. In a simple example, with no rules on fishing amounts, fishers will catch as much fish as they can in the short run because every fish not caught by themselves means more caught by others, leading to there being no more fish to catch in the long term, creating a worst outcome for all. In this manner, the tragedy of commons can be looked at as a prisoner’s dilemma situation, where each player using their dominant strategies leads to a worse outcome for all.
As expected from game theory, the paper finds that not cooperating would indeed have been the dominant strategy for Norway, the EU, and Iceland/the Faroe Islands to not cooperate. Each player would have maximized their long-run economic yield by doing so. The paper additionally explains that this is not actually what happened during the dispute; only Iceland and the Faroe Islands overfished, not all the countries involved. The authors state that a perspective based purely on game theory thus cannot explain the real-life outcomes. It was most likely the fear of sanctions and blockades, which indeed was put in place in 2014, that deterred countries like Ireland and Norway from overfishing as well.
Link to the paper: https://www.sciencedirect.com/science/article/pii/S016578361500199X?via%3Dihub