Understanding Bycatch

Fishermen sometimes catch and discard animals they do not want, cannot sell, or are not allowed to keep. This is collectively known as “bycatch.” Bycatch can be fish, but also includes other animals such as dolphins, whales, sea turtles, and seabirds that become hooked or entangled in fishing gear.

For NOAA Fisheries, bycatch refers to “discarded catch of marine species and unobserved mortality due to a direct encounter with fishing vessels and gear.” These unintentionally caught animals often suffer injuries or die.

NOAA Fisheries is committed to continuing to reduce and minimize bycatch now and into the future. Our investment in bycatch reduction is spread across multiple program areas and laws including the Magnuson-Stevens Fishery Conservation and Management Act, Marine Mammal Protection Act, and Endangered Species Act.

Unwanted catch is an issue both ecologically and economically. Animals that are discarded often die and cannot reproduce, impacting marine ecosystems. Bycatch can slow the rebuilding of overfished stocks, and place protected species such as whales and sea turtles at further risk. Bycatch of species like corals and sponges can cause damage to protected corals and to important fish habitat.

Fish

Bycatch of non-target fish can contribute to overfishing and slow efforts to rebuild fish stocks.

Bycatch can also have negative economic and social impacts on fishermen and their communities. For example, a fishery may close early because of high bycatch of a non-target species. Ecologically, bycatch can change the availability of prey, which affects marine ecosystems and the productivity of fisheries.

Protected species

Bycatch can negatively affect species such as dolphins, sea turtles, protected fish, and whales by harming animals, contributing to population declines, and impeding population recovery. Other impacts of fisheries on marine mammals may include removal of their preferred prey and sometimes habitat damage.

Fisheries bycatch is a threat to marine mammals worldwide. Bycatch occurs when marine mammals are incidentally caught in fishing gear (e.g., hooked, entangled, or trapped) or when they eat bait or catch. Bycatch of marine mammals can occur during active fishing operations using mobile or fixed fishing gear, and it also can result when fishing gear has been lost, discarded, or is otherwise no longer being used to harvest fish (also known as marine debris). Reducing bycatch and harmful interactions with marine mammals is a top priority for NOAA Fisheries and our partners.

Bycatch in fishing operations is one of the most serious threats to the recovery and conservation of sea turtle populations. To reduce this threat, NOAA Fisheries has instituted fishery observer programs to document the bycatch of protected species, including sea turtles, and implement regulations to reduce sea turtle bycatch in the Pacific and Atlantic Oceans and the Gulf of Mexico. NOAA Fisheries requires changes to fishing practices to reduce sea turtle bycatch in several fisheries including the Hawaii, California, and Atlantic pelagic longline fisheries; the California/Oregon drift gillnet fishery; and the mid-Atlantic gillnet, Chesapeake Bay pound net, and southeast shrimp and flounder trawl fisheries. We regularly collect observer information and stranding data to determine whether additional conservation measures are needed to recover sea turtles.

NOAA Fisheries tracks bycatch several ways: human observers placed on fishing vessels, electronic technologies that record and transmit data, logbook information that fishermen are required to record, and voluntary surveys of fishermen.

We publish bycatch estimates for important U.S. fisheries through our series of National Bycatch Reports and updates.

To better understand bycatch, NOAA Fisheries works with domestic and international partners, including regional fishery management councils, take reduction teams, the fishing industry, academic groups, and environmental organizations. Over the past 40 years, we’ve worked with our stakeholders to develop new tools and approaches for reducing bycatch, and successfully implemented management measures.

Learn more about the history of bycatch management in the United States. 

2016 National Bycatch Reduction Strategy

We released the 2016 National Bycatch Reduction Strategy, which guides and coordinates our efforts to reduce bycatch and bycatch mortality in support of sustainably managing fisheries and recovering and conserving protected species.

It depends. Bycatch of protected or regulated species generally cannot be landed and sold. But the 2016 National Bycatch Reduction Strategy encourages “increased utilization" of fish that are lawfully harvested but discarded because their market value is too low. Finding ways to use this legal catch can help reduce the magnitude of bycatch and provide economic benefits to the fishing industry.

Proven solutions exist to reduce bycatch and more are being developed in partnership with the fishing industry and other groups. Fishermen use many different types of fishing gear and catch a wide variety of species. We work with partners to understand fishing gear and to develop, test, and implement alternative fishing gear. For instance, NOAA Fisheries and our partners developed turtle excluder devices to reduce sea turtle mortality in the southeastern shrimp trawl fishery.

Understanding fishing gear is important in minimizing bycatch and a reason NOAA Fisheries funds the Bycatch Reduction Engineering Program. This program supports the development of technological solutions and changes in fishing practices designed to minimize bycatch.