FISHWATCH GLOSSARY

Angler

A person catching fish or shellfish with no intent to sell, i.e. a recreational fisherman.

Aquaculture

The breeding, rearing, and harvesting of plants and animals in natural and human-made water environments, including ponds, rivers, lakes, and the ocean. Also commonly known as fish or shellfish farming.

Benthic

Of or pertaining to the seafloor (or bottom) of a water body.

Biomass

The total weight of a group or stock of living organisms (e.g. fish, plankton) or of some defined fraction of it (e.g. spawners) in an area, at a particular time.

Bycatch

Sometimes when fishermen are fishing for one species, they unintentionally catch other creatures that live near that species. These creatures may include other fish species, marine mammals, turtles, or even seabirds that are diving to catch their own food. Fishermen try to avoid bycatch because it takes time and energy away from catching their target species. Managers try to reduce bycatch and its impacts in a number of ways, such as working with fishermen to develop new gear that is more efficient in catching the target species and closing areas to fishing where or when the probability of bycatch is high.

Catch

The total number (or weight) of fish caught by fishing operations. Catch includes all fish killed by the act of fishing, not just those landed.

Catch Limit

The weight limit on fish that fishermen can catch in a fishing season.

Catch Share

A fishery management program that dedicates a secure share of the total fishery catch to individuals, cooperatives, communities, or other entities. Catch share recipients are responsible for terminating fishing activity when their specific share is reached.

Demersal

Living in close relation with the bottom and depending on it. Cods, groupers, crabs, and lobsters are demersal resources.

Ecosystem

The community of animals and plants interacting with the land, water, weather, and the surrounding human activities.

Endangered Species

Any species that is in danger of extinction throughout all or a significant portion of its range, as defined in the Endangered Species Act.

Fishery

The combination of fish and fishermen in a region, the latter fishing for similar or the same species with similar or the same gear types.

Fishing Effort

The amount of fishing gear of a specific type used on the fishing grounds over a given unit of time (for example, hours trawled per day, number of hooks set per day, or number of hauls of a beach seine per day).

Fishing Gear

The equipment used for fishing (e.g. gillnet, hand line, harpoon, haul seine, longline, bottom and midwater trawls, purse seine, rod-and-reel, pots and traps). Each of these gears can have multiple configurations.

Fishing Season

The weeks or months during which it is legal to catch a kind of fish.

Fish Stock

The part of a fish population usually with a particular migration pattern, specific spawning grounds, and subject to a distinct fishery.

Gillnet

With this type of gear, the fish are gilled, entangled or enmeshed in the netting. These nets can be used either alone or, as is more usual, in large numbers placed in line. These nets may be used to fish on the surface, in midwater or on the bottom.

Habitat

An ecological or environmental area where a particular species of animal, plant, or organism lives. It can be the natural environment of the organism or the physical environment that surrounds a population.

Harvest

The total number or weight of fish caught and kept from an area over a period of time.

High Seas

All waters beyond the Exclusive Economic Zone (EEZ) (more than 200 nautical miles) of the United States and beyond any foreign nation’s EEZ.

Hook-and-Line

A type of fishing gear consisting of a hook tied to a line. Fish are attracted by bait that is placed on the hook, and are impaled by the hook when biting the bait.

Illegal, Unreported and Unregulated fishing (IUU)

Fishing that violates national or international law or rules, hasn’t been reported in areas where reporting is required, or is inconsistent with relevant international laws or rules. Either the fishing activities are not regulated or the involved fishing vessels are not able to be regulated. Illegal activities can include fishing without a license or quota for certain species, unauthorized transshipments to cargo vessels, failing to report catches or making false reports, keeping undersized fish that are otherwise protected by regulations, fishing in closed areas or during closed seasons, and using prohibited fishing gear. By dodging conservation and management measures, those engaging in IUU fishing can cut corners and lower their operating costs. As a result, their illegally-caught products provide unfair competition for law-abiding seafood industries in the marketplace.

Incidental Take

The “take” of protected species (such as marine mammals, sea turtles, or seabirds) during fishing. “Take” is defined as to harass, harm, pursue, hunt, shoot, wound, kill, trap, capture or collect, or to attempt to engage in any such conduct.

Jigging

A method of fishing using lures on a vertical line that snag fish when they pass near. The line is moved up and down (jigged) by hand or mechanically.

Landings

The number or poundage of fish unloaded by commercial fishermen or brought to shore by recreational fishermen for personal use. Landings are reported at the locations at which fish are brought to shore.

Longline

Fishing method using a horizontal mainline to which weights and baited hooks are attached at regular intervals. The horizontal mainline is connected to the surface by floats. The mainline can extend from several hundred yards to several miles and may contain several hundred to several thousand baited hooks.

MAXIMUM SUSTAINABLE YIELD (MSY)

MSY is the largest long-term average catch or yield that can be taken from a stock or stock complex under prevailing ecological, environmental conditions and fishery technological characteristics.

Mesh Size

The size of holes in a fishing net. Minimum mesh sizes are often prescribed by regulations in order to avoid the capture of the young of valuable species before they have reached their optimal size for capture.

Metric Ton (t, mt)

1,000 kilograms, equivalent to 2,204.6 pounds.

Multispecies Fishery

Fishery in which more than one species is caught at the same time. Because of the imperfect selectivity of many fishing gears, many fisheries are “multispecies,” but the term is often used to refer to fisheries where more than one species is intentionally sought and retained.

Overfishing

A stock that is subject to overfishing has a fishing mortality (harvest) rate that is higher than the rate that produces maximum sustainable yield (MSY).

Overfished

When the population is too low, or below a prescribed threshold. In the U.S., overfished populations are required to be managed under rebuilding plans that, over time, return the population to optimal levels.

Pelagic

Inhabiting the water column as opposed to being associated with the sea floor; generally occurring anywhere from the surface to 1,000 meters.

Pots

Traps, designed to catch fish or crustaceans, in the form of cages or baskets of various materials (wood, wicker, metal rods, wire netting, etc.) and having one or more openings or entrances. Usually set on the bottom, with or without bait, singly or in rows, connected by ropes (buoy-lines) to buoys on the surface showing their position.

Processing

The preparation or packaging of fish to render it suitable for human consumption, retail sale, industrial uses, or long-term storage, including but not limited to cooking, canning, smoking, salting, drying, filleting, freezing, or rendering into meal or oil, but not heading and gutting unless additional preparation is done.

Protected Species

Refers to any species which is protected by either the Endangered Species Act (ESA) or the Marine Mammal Protection Act (MMPA), and which is under the jurisdiction of the National Marine Fisheries Service (NOAA Fisheries). This includes all threatened, endangered, and candidate species, as well as all marine mammals (warm-blooded animals that live in marine waters and breathe air directly–porpoises, dolphins, whales, seals, and sea lions, but excluding walruses).

Purse Seine

Nets characterized by the use of a purse line at the bottom of the net. The purse line enables the net to be closed like a purse and retain all the fish caught. Purse seines, which may be very large, are operated by one or two boats.

Rebuilding

Implementing management measures to allow a depleted stock, or population, to grow back to a predefined target level. A rebuilding plan is the document that describes these management measures.

Recruitment

The number of young fish each year reaching a size or life stage that can be caught by fishing gear.

Spawning

The release of eggs, fertilized or to be fertilized.

Species

A group into which animals or plants are divided according to their shared characteristics.

Stock Assessment

The process of collecting and analyzing biological and statistical information to determine the changes in the abundance of fishery stocks in response to fishing, and, to the extent possible, to predict future trends of stock abundance. Stock assessments are based on resource surveys; knowledge of the habitat requirements, life history, and behavior of the species; the use of environmental indices to determine impacts on stocks; and catch statistics. Stock assessments are used as a basis to assess and specify the present and probable future condition of a fishery.

Survey

Sampling, collecting, observing, or surveying fish or fishery resources, on board scientific research vessels, to increase scientific knowledge of fishery resources or their environment.

Sustainability

Ability to persist in the long-term.

Threatened Species

Species that are likely to become endangered within the foreseeable future.

Trawl

Towed net consisting of a cone-shaped body closed by a bag or codend and extended at the opening by wings. It can be towed by one or two boats and, according to the type, used on the bottom or in midwater (pelagic).

Trolling

A surface and subsurface fishing method in which lines with baits or lures are dragged by a vessel at a speed of 2–10 knots.

For more, see NOAA Fisheries Glossary. (PDF)