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Input Controls and Interventions

In the presence of input controls, some interventions regain a positive outcome.

Input controls refer to various regulatory mechanisms to reduce or limit the amount of fishing. Input controls are sometimes implemented by issuing a limited number of fishing permits, so as to limit the number and type of boats allowed to take the fish. Other common types of input controls are quotas, where the total tonnage of fish that can be taken from the ocean is limited.

Quotas may be a simple way to promote fish stock recovery, but by limiting fishers' ability to fish, they also have a direct, negative impact on their livelihoods.

Combining input control quotas with other fisher community support strategies can produce better outcomes than just quotas alone. For example, implementing a strategy to help fishers improve the quality of their tuna catch, in addition to implementing access control quotas, improves fisher, middleman, and exporter profits, while sustaining fish stocks.

In the interactive section below, we show an intervention that increases fishers' incomes without requiring them to take more fish from the ocean. (Such as helping increase the quality of fish brought to shore.) Increasing productivity, as in making boats faster or baits more efficient, would allow fishers to take more fish from the ocean, meaning more stock depletion. In contrast, increasing fish quality, as in providing ice or refrigeration to maintain freshness, can raise family income without taking more fish out of the water.

Add input controls, and combine them with subsidies to increase fish quality, to see the effect this has on the fishers and the fishery.


Increasing profitability due to global demand for food products is bringing in more fishers and threatening the fish stock

Controlling the number of fishing permits forces the number of boats to remain stable

Increasing fish quality leads to immediate livelihood improvements but attracts too many additional fishing boats

Controlling the number of fishing permits forces the number of boats to remain stable

In the current conditions, stocks slowly decline due to open access

Stocks remain stable when not overfished

More boats lead to faster stock decline

Stocks remain stable when not overfished

Fisher profits' rise is eventually negated by declining stocks

Fisher incomes are now driven up by increasing global demand for wild tuna

Without input controls, increasing fish quality backfired

With entry limits, the intervention is able to directly improve fishers incomes without speeding up stock decline