National Oceanic & Atmospheric Adminstration (NOAA)

   Fisheries & Aquaculture
   Aquaculture

Many commercial and artisanal fisheries have been conducted sustainably for decades. So, at some level, we must know how to manage fisheries well. Yet, many other fisheries have been severely depleted. Why?

There are several factors at work. Ocean productivity varies on many different time scales, from annual seasons to cycles several decades long. Fish abundance roughly follows these cycles and patterns. Modern fisheries science has been slow to recognize, model, and quantify the dependence of fish abundance and productivity on ocean productivity. And unfortunately, fisheries management has been even slower to adjust allowable catches based on ocean productivity patterns. Pollution has also taken a toll on fisheries, reducing the quality of the habitats that support target fish populations, contaminating the flesh of food fish, and altering ocean food webs. The loss or degradation of fish habitats such as estuaries, wetlands, seagrass meadows, and kelp forests as a result of poorly planned coastal development and agriculture and offshore dumping is probably the greatest long-term threat to fisheries and nearshore marine ecosystems.

Over a shorter time horizon, however, it is clear that overfishing is a major threat to ocean ecosystems. Several studies show that fish populations have plummeted as landings and fishing effort have risen. In many cases, this was the expected result, as managers decided to fish down the stocks to thin them out, theoretically increasing their productivity. However, in other cases, scientific estimates of productivity were off and this fishing down strategy depleted the populations below levels that can be expected to maximize yield. An additional line of evidence that overfishing has affected the ocean profoundly comes from marine reserves, where fishing has been banned. In most cases, exploited species are much more abundant within the reserves than on similar habitats that are fished. Similarly, the average size of exploited species tends to be significantly larger in reserves than on the fishing grounds. Moreover, species diversity tends to be much higher within reserves. Population densities size distributions of unexploited species tend to be quite similar in the reserves and on the fishing grounds (except for the species diversity of infaunal invertebrates, which is often greatly reduced by trawling). If climate change or pollution were causing the large declines in fish populations that have been observed in some fisheries, we would expect to see similar declines in other, unexploited species in marine reserves and on the fishing grounds. Similarly, we would expect to see no differences in abundance or size distribution in reserves, since populations in reserves would be exposed to climate change and pollution too.

In many multi-species fisheries, where low productivity species (slow-growing, late to mature, long-lived) mix with high productivity species (fast-growing, highly fecund, early maturity, short-lived), serial depletion has occurred. Because trawls, which dominate many fisheries, tend to catch all species at similar rates, the low productivity species are depleted first and so on up to the higher productivity species. In fisheries that are managed to protect "weak stocks", serial depletion results in severe constraints when bycatch is high. Allowable catch levels of the depleted weak stocks are often set very low or banned altogether; however, fishermen cannot avoid taking some of these depleted species even as they target the more productive species. If the bycatch of the weak stocks exceeds the allowable limit, the multi-species fishery shuts down, even though lots of fish could be sustainably harvested (if bycatch rates could be significantly reduced).

Overfishing, high bycatch rates, the use of gear types that damage habitat (like trawls and dredges), and the large subsidies supporting fisheries (totally over $15 billion per year) are all symptoms of an underlying problem. In most fisheries that are exhibiting declines in landings and revenues, overfishing, bycatch, and habitat damage, actions that result in the symptoms are actually rational given the way the fisheries are managed. In these fisheries, secure privileges to catch certain amounts of fish are not specified, so naturally individual fishermen compete to maximize their individual shares of the catch. No incentives for conservation exist in this situation, because every fish conserved can be caught by another fisherman. The competition to maximize catch often results in a fishery "arms race", resulting in the purchase of multiple vessels, the use of powerful engines and large vessels, and the use of highly efficient gear like trawls. Capital costs for vessels and gear increase as a result. At the same time, the competition to maximize catch often results in supply gluts, as most fishermen land large catches at the same time during seasons that become shorter and shorter due to the excessive number of vessels participating in the fishery. Prices paid to fishermen are reduced by the glut, and the quality of fish supplied to consumers declines as well (from fresh to frozen). The non-market costs associated with this kind of behavior -- such as habitat damage, overfishing, and bycatch -- are passed on to the fishery and onto society as a whole.

Most of the solutions that have been implemented or proposed to fix the world's fisheries center on command-and-control measures: regulators or courts telling fishermen how to fish through the imposition of controls on effort (e.g., fishing vessel length, engine horsepower, gear restrictions, etc.). Prescriptions like these work against strong economic incentives for maximizing catch, which are not addressed by such measures, and are of course usually resisted by fishermen. Often, prescriptions create incentives for "work-arounds" and set up a cat-and-mouse game between fishermen and regulators - for example, if regulators impose a restriction on vessel size, fishermen may purchase two vessels to maintain high catch levels.

As in most natural resource problems, more effective solutions will address the fundamental drivers of unsustainable fisheries. In this case, the key necessary reform will be to designate secure catch privileges. It is important to understand that such privileges can be allocated to different kinds of entities in different ways, and indeed, they should be tailored to specific fisheries and communities to fit with local customs, traditions, values, and social structure. For example, Territorial Use Privileges may be most appropriate for fishing communities with long histories of using resources in a particular location or area. Community Development Quotas may be effective for remote communities with few other assets. Catch shares can be allocated to fishery cooperatives with the institutional capacity to manage their allocation and remain accountable to national fishery management and conservation standards. Community-based co-management entities can also hold catch share allocations and appear to work well when leadership patterns and processes for consensus-building are clearly defined and workable. Individuals can also be allocated Individual Fishing Quotas in fisheries that are more industrialized, fish over extensive grounds, and land in many different ports. Empirical studies on dozens of fisheries around the world show clearly that the designation of secure catch privileges in ways that fit a specific fishery and community improve economic performance, substantially increasing revenues, profits, and job stability (though jobs are usually lost in the case of highly overcapitalized fisheries) and improve conservation performance. Indeed, in some cases, true stewardship is achieved by holders of secure catch privileges.

Fixing the fundamental economic problems underlying the poor conservation and economic performance of many fisheries will facilitate the implementation of other kinds of conservation measures, such as Marine Protected Areas, area closures or gear restrictions, etc. Spatial management to protect habitat, such as MPAs and area closures/restrictions, are good interim management tools. However, for comprehensive protection of all ocean ecosystems, we will need to transition to management based on habitat protection performance standards to complement stock conservation and bycatch performance standards, which are now being implemented in some fisheries. Performance standards specify desired environmental outcomes, in contrast to prescriptions that specify mandated behaviors. As a result, performance standards tend to create incentives for innovations (for example, in gear technology and fishing practices) to meet goals rather than resistance and efforts to get around prescriptions.

The transition to designated access privilege management as recommended by the US Commission on Ocean Policy, interim conservation and management measures, and a move toward performance standards for comprehensive ocean conservation and management will require good science, political will, and financing. Financing may be the key that unlocks the ability to do better science and build political will by building consensus through education and pilot projects. Adequate appropriations for fisheries management and research have usually been difficult to obtain either at the federal, state, or international level. Thus, we need to "think different" about financing and look to more creative approaches. For example, the California Ocean Protection Act authorizes the creation of an innovative fisheries revolving loan fund that would invest in fisheries reform, require improved conservation performance, and recoup its investments from fisheries that are more profitable as a result of a transition to designated access management or other effective reforms. If the initial investments of the Fund are successful, there will be a potential for leveraging vast amounts of private capital to complement the state's initial investment, due to the return on investment. The result could be a self-sustaining source of financing for fisheries reform, management, and monitoring which could free up state resources for conservation and management measures that cannot produce a return on investment. 3.14.06