Management Tools & Enforcement in Commercial Fisheries

Fishery management has three general goals: (1) maximize sustainable catch while also limiting unsustainable catch to provide long-term renewable food for society, (2) improve and maintain livelihood for those in the industry, and (3) ensure continued profit for those holding capital (for a more in-depth discussion of fishery management goals see here). To accomplish these goals, fishery managers use regulatory tools to create and enforce fishery policies. Ideally, the policies are well informed by fishery science, social science, and economics to achieve triple bottom line success.

In this section, we cover different kinds of policies and tools, weigh their outcomes, and discuss how they fit into management frameworks. However, the complexity and nuance of fishery management must be viewed through a lens of enforcement and capacity.

Enforcement & Capacity

Rules are followed as well as they are enforced. For example, it is illegal to jaywalk in New York City. This offense happens millions of times per day because it is almost never enforced. Just over the river at Metlife Stadium, where New York’s football teams play, a security guard is positioned every few yards around the field to prevent New Yorkers from illegally walking onto the field and disrupting the game. Those that make a dash for it are always caught. For this reason, very few people attempt a run onto the field—despite the attention, fame, and satisfaction of fulfilling a dare that would come from it. Different levels of enforcement produce different outcomes. Fisheries management is no different; for example, a well-enforced marine protected area will be fished less than one with little to no enforcement.

The level of enforcement helps determine how closely rules are followed. Successful enforcement hinges on the capacity, or capability, of the governing body. Capacity is directly tied to wealth: money hires more fishery managers, observers, and officers (the people tasked with enforcement), supports better organization and logistics, buys bigger & better boats, and prompts sustainability. Indeed, the wealthiest countries with the most established and well-funded management systems have the most sustainable commercial fisheries. Countries with less capacity (read: poorer countries), have less ability to enforce policies and thus less sustainable commercial fisheries. For example, a country that can afford to enforce their marine protected areas will see less illegal fishing than a country with little to no enforcement.

This figure from Melnychuk et al. 2016 ranks fishery sustainability by country based on five different factors (each is an aggregate of several measures). You can see that developed countries with greater capacity are near the top while countries with lower capacity are near the bottom.


Management Tools & Measures

Total Allowable Catch (TAC)

When fishery scientists perform stock assessments, they often recommend a total allowable catch (TAC) for a given fish population or stock. A TAC is meant to keep a fishery at MSY or limit catch to rebuild the stock to MSY. A TAC is the most important tool for fishery managers, though obtaining and enforcing one requires the appropriate capacity.

Managing physical objects

Registering a fishing boat and obtaining a permit to harvest are the first steps in starting a commercial fishing operation; naturally, the first step in fishery management is regulating boats. All boats are required to be licensed, registered, and/or permitted by the governing body where they fish. Similar to a department of motor vehicles, this gives a central location for managers to regulate the kind of boat and size of boat allowed in the water. Many fisheries prefer to have fewer large boats rather than many smaller boats because they are easier to manage. Managers can also require cameras or human observers onboard to ensure other rules are being followed.


Next in a fishing operation is the kind of fishing gear that will be used. Fishing gear is chosen depending on the species, depth, weather, boat, and crew; though the most efficient way to catch a target species is not always the most environmentally friendly. Gear restrictions, or limitations on the kind of fishing gear allowed in a fishery are meant to curb the amount of bycatch produced. A classic example is turtle excluder devices (TEDs). Sea turtles are susceptible to being caught in trawl nets and drowning; nets with TEDs allow the turtles to escape while keeping the fish. Our explainer on all different kinds of commercial fishing gear & techniques can be found here.

Turtles can swim through the TED in a trawl net.

Spatial & Temporal Tools

Fishery managers can also restrict when and where fishermen can fish. Often closed seasons are the easiest regulation to enforce. These kinds of spatial & temporal closures are great for protecting fishes’ reproduction: Fish reproduce in many different ways, but they all depend on timing and specific locations to spawn—protecting those times or seasons and location is important in ensuring sustainability. For example, many crustaceans like crab and lobster carry their eggs for a season; closing a crustacean fishery during the egg carrying season will ensure those eggs get to hatch and the fishery is sustained. Many species of fish also meet in specific locations to spawn. It would be so easy for a fishing boat to wait on a known mating spot and wipe out a population—protecting those spawning aggregations is crucial.

Marine Protected Areas

The most well-known kind of spatial tool is a marine protected area (MPA). An MPA functions like a terrestrial protected area: it is a piece of Earth governed by special rules meant to restrict some kind of use in that area. Usage restrictions can range from minimal, like “do not catch a particular species of fish in this area,” to maximal: do not even enter this area. MPAs also range in size from less than 1 km2 to the largest in the world at nearly 2 million km2.

With so many uses for the ocean (recreation, fishing, farming, drilling, etc.), MPAs play a large role in marine spatial planning—essentially designating what and where activities get to happen and how conservation and preservation fit in. MPAs that have preservation as their goal and restrict any kind of fishing are called no-take MPAs or marine reserves.


Catch Shares

Catch shares are a relatively new tool, used as way to divide up the TAC. Historical fishery management mostly relied on gear restrictions and spatial & temporal restrictions to manage fisheries. This created a few issues in the fishing industry:

  • Many fisheries became a “race” where competing boats fished as fast and as hard as they could within the time limits.
  • This incentivized fishing boats to go out in rough and dangerous weather. Many fishing deaths can be attributed to rough conditions.
  • Even if there was a TAC, boats still tried to catch as many pieces of the pie as they could
  • Fresh fish of a certain species was only available to restaurants and consumers during specific times of the year.

Catch shares aim to fix these problems by starting with a TAC and working backwards. Once the total amount of catch is determined for a species, fishermen are allotted a set amount to catch (a catch share). This allows the fishermen to go out when it is safe, convenient, and profitable for them. The Alaskan king crab fishery (of Deadliest Catch fame) saw over seven deaths per year in the 1990s. After a catch share program was implemented in 2006, there was only one death in the next 6 years. Catch shares also add value to the fishery as fresh fish can be available more often to restaurants and consumers over a longer fishing season or even year-round.

However, catch shares can be controversial. The allotment of shares is not always done fairly. Shares are capital and can be bought, sold, or leased. Large share holders have power over lesser share holders and can wield it in unjust ways.

These issues are typically due to initial design and implementation of the program by fishery managers. Catch shares implemented now have the ability to correct past mistakes and benefit from revisions, but many of the early programs are riddled with imperfections.

Management philosophies

Best available science

Management decisions should be based on the best available science.

Ecosystem-based management

Ecosystem-based management (EBM) is a holistic approach to natural resource management that considers every aspect of an ecosystem, including humans, rather than concentrating on one single species or ecosystem issue. EBM focuses on maintaining sustainable relationships within an ecosystem.

Adaptive management

Adaptive management is not a specific tool, but a philosophy of sorts. As social and environmental conditions change, fishery management needs to be able to quickly adapt. An adaptive management structure that encourages iterative and salient policy change can address environmental change and uncertainty, but is more complicated to implement and enforce by the governing body. Despite the additional effort, many prominent fishery scientists advocate that adaptive management is the way to go. Encouraging stakeholders, especially fishermen, to participate in the decision-making process adds to adaptive management and is referred to as participatory adaptive management.

Top-down vs bottom-up

Top-down management is centralized. A large regulatory body like NOAA creates, implements, and enforces rules to be followed by fishers. Top-down approaches can be effective with high capacity regulatory bodies (like NOAA), but can also create resentment amongst fishermen and women who hold little decision-making power.


Community-based management empowers direct stakeholders to collectively manage their own fisheries. In small-scale fisheries this often leads to better compliance with less need for enforcement, but on large, global scales, community-based management is difficult (re: tragedy of the commons).


This post is part of Sustainable Seafood 101

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