Step 1: Understanding the Concept:
The "Tragedy of the Commons" is an economic theory describing how individuals with access to a shared, unregulated resource act independently in their own self-interest, ultimately depleting or spoiling that resource.
Step 2: Detailed Explanation:
In open-access marine fisheries, fish stocks are a shared, common-pool resource with no clear ownership.
Because there is no incentive for individual fishers to conserve the resource (as any fish left behind may be caught by someone else), fishers compete to maximize their catch.
This collective behavior leads to overfishing, resource depletion, and economic inefficiency.
Step 3: Final Answer:
Thus, the "tragedy of the commons" in fisheries refers to the overexploitation of shared fishery resources.