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abundance
Degree of plentifulness. The total number of fish in a population or on a fishing ground.
alevin
The developmental life stage of young salmonids and trout that are between the egg and fry stage. The alevin has not absorbed its yolk sac and has not emerged from the spawning gravels.
anchovies
Small silvery fishes that swim in big schools. Anchovies are eaten by tuna, salmon, and many other predatory fishes.
antibiotic
A chemical compound which can inhibit reproduction or cause the destruction of bacteria.
apex predators
Species on the top of the food chain that depend on the availability of smaller fish for sustenance.
aquaculture
The production and husbandry of aquatic animals and plants in a controlled environment.
benthic
On or near the bottom of a lake, river or ocean.
bivalve
A mollusk, such as an oyster or a clam, that has a shell consisting of two hinged valves.
bluefin tuna
A group of tuna species with iridescent blue skin. Bluefin are some of the ocean's biggest, fastest predators. They migrate across the world's oceans and can weigh up to 2,000 pounds (907 kilograms).
bottom trawling
A type of fishing that drags a trawl net, sometimes equipped with rollers or "rock-hoppers," over the seafloor. Bottom trawls can be very destructive to seafloor habitats that fish and other wildlife depend on.
bycatch
Harvest of fish or shellfish other than the species for which the fishing gear was set. Examples are blue crabs caught in shrimp trawls or sharks caught on a tuna longline. Bycatch is also often called incidental catch.
carp
An herbivorous freshwater fish (Cyprinus carpio) originally from Asia that is frequently bred in ponds and lakes. The carp was also introduced into Europe, where it is extensively reared in artificial ponds.
capacity
The maximum number of organisms that can use a given area of habitat without degrading the habitat and without causing stresses that result in the population being reduced.
carnivorous
Term used to describe the diet of an organism who eats living animals
catfish
Any of numerous scale-free, chiefly freshwater, bottom-living fishes of Eurasia and North America characteristically having whisker-like projections extending from the mouth. It is a food fish of the southern United States, farmed extensively in Mississippi. The omnivorous fish have been bred to require minimal amounts of fishmeal and fish oil.
catch limits (also referred to a "total allowable catch" or "quota")
A fisheries management tool implemented to limit the quantity of a species of fish that fishermen are permitted to land in a given amount of time or geographical area.
channel
The deepest part of a stream or harbor, where most of the water flows.
Chilean sea bass
A fish that lives in the deep sea near Chile. The species was called "Patagonian toothfish" until fish sellers decided it needed a name that would sound more appealing to consumers. This slow-growing species is in serious trouble from overfishing.
cod
A large coldwater fish that often lives close to the seafloor. Cod have firm white flesh; for centuries, Atlantic cod have been important to people of many nations as a food fish.
commercial extinction
Extinction is a process that goes from depletion (a fish population or species severely reduced by overfshing) to commercial extinction (the population or species becomes too rare to catch profitably) to biological extinction (the species no longer exists).
commodity
Product. Goods and services which are the result of production processes normally intended for sale on the market at a price that is designed to cover their costs of production.
community
All of the plants and animals living in a specific area (habitat), often described by the most abundant or obvious organisms. The kelp forest community means all the animals and plants that are part of the kelp forest.
compromise
An agreement between two parties in which each side makes concessions.
conservation
The practice of protecting nature from loss or damage.
contamination
Polluted or impurity caused by contact with another substance.
continental shelf
The submerged shelf of land that slopes gradually from the exposed edge of a continent to where the drop-off to the deep seafloor begins.
coral
A group of invertebrate animals related to sea anemones. Individual coral animals have soft bodies topped by a ring of stinging tentacles for catching food. Some kinds of coral build hard limestone skeletons; when they die, other corals build on top until a great reef is formed.
deficit
The quantity by which an amount is less than the needed amount.
depletion
For renewable resources, the part of the harvest, logging, catch and so forth above the sustainable level of the resource stock; for non-renewable resources, the quantity of resources extracted.
dioxins
A general term referring to a class of structurally and chemically related compounds, including the "dioxin-like" Biphenyls (PCBs). Dioxins are chemical contaminants that are known to cause cancer in humans.
dissolved oxygen
The volume of oxygen dissolved in water.
dredge
A net attached to a frame that's dragged along the ocean floor to collect animals.
eco-label
A logo placed on product labels, usually indicating that a manufacturer has used “environment-friendly” practices when creating a product.
ecosystem
The natural system in which energy and nutrients cycle between plants, animals and their environment.
effluent
Discharge of liquid waste or pollution. Effluents can contain bacteria, viruses, excessive nutrient loads and chemicals that are harmful to wildlife and human health.
(Eyed) egg
A fish egg containing an embryo that has developed enough so the eyes are visible through the egg membrane.
entrepreneur
A person who takes on the risk of a business venture hoping to profit.
escapes
When a farmed fish finds its way out of a netcage and into the open water. Escapes are often as the result of storm damage or human error.
estuary
The area where a river meets the ocean.
factory trawler
A large ship equipped to catch, clean and freeze fish for market.
filter feeder
An aquatic animal, such as a clam, barnacle, or sponge, that feeds by filtering particulate organic material from water.
fisheries management
The effort to regulate where, when and how people fish, and how many fish they catch. The intent is usually to protect fish populations so that people can continue to fish. Most fisheries management is done by government agencies such as the U.S. National Marine Fisheries Service.
fishery
The occupation or industry of catching, processing, and selling fish and shellfish; an area where fish or shellfish are caught.
fishing pressure
The amount of fishing effort for a certain species of fish or shellfish. If there's heavy fishing pressure on sharks, it means that lots of sharks are being caught by fishers.
fishmeal
Ground dried fish used as a component of formulated feed for farmed (carnivorous) fish and livestock.
fish oil
Oil obtained from fish, a vital ingredient in the formulated feed for carnivorous fish.
flatfishes
A general term for fishes like flounder, sole and halibut that are flattened for life on the seafloor.
food chain
The relationship between plants and animals that shows who eats what. Energy is transferred from one organism to another through the food chain.
food security
The notion that all people in a community, especially the most vulnerable, have reliable access to good nutritious food into the future.
food safety
The consideration of human health risks associated with certain food products.
fry
A stage of development in young salmon or trout. During this stage the fry is usually less than one year old, has absorbed its yolk sac, is rearing in the stream, and is between the alevin and parr stage of development.
gill net
A type of fishing net that catches fish by their gills or gill covers.
habitat
An organism's home; for example: in the midwater, on the seafloor, near the surface or in a tide pool.
halibut
A large fish with a flattened body adapted for life on the seafloor.
harvesting
The catching of seafood.
harvesting gear
Gear used to extract fish from the water
hatchery
A place where the eggs of fish are hatched
herbivore
An animal that feeds chiefly on plants.
herbivorous
Term used to describe the diet of an organism who eats plants
Individual Fishery Quota (often referred to as "IFQ")
A regulatory permit under a limited access system to harvest a specified quantity of fish, expressed by a unit or units representing a percentage of the total allowable catch.
Infectious Hematopoietic Necrosis (IHN)
A viral disease of salmon that exists in the wild but is thought to become amplified within the confines of salmon farms. Outbreaks have occurred in Atlantic salmon farms in British Columbia. The virus is shed via feces, urine and external mucus, whereas kidney, spleen, encephalon and the digestive tract are the sites in which virus is most abundant. Infection is often lethal due to the impairment of osmotic balance and hemorrhages. The visible signs of the disease are lethargic fish showing occasional bouts of abnormally frenzied activity that usually precedes death. The abdomen is often swollen and eyes may be protruding.
Infectious Salmon Anemia
A salmon disease that originates in the wild, but tends to be greatly amplified within the confines of a crowded net cage or pond with high stocking densities.
kilometer
A measure of length equal to 1,000 meters or about 5/8 of a mile.
landed
Brought to land, brought to shore; in the case of a fish, caught and brought to land.
landings
The quantities of fish caught and brought to land by fishermen.
larva
The young and immature form of an animal, which must change to become an adult.
longlining
A type of commercial fishing which uses hundreds of baited hooks on a line that can be many miles long.
mangrove
A tree that grows along tropical coasts in salty ocean water, Their extensive root systems provide a breeding ground for plant and marinelife biodiversity, and also aid in building up coastlines.
marine protected area
Any area of the marine environment that has been reserved by federal, state, territorial, tribal, or local laws or regulations to provide lasting protection for part or all of the natural and cultural resources therein.
marine reserve
A discrete area of the marine environment in which, at a minimum, extractive activities such as fishing, mining, and shell collecting are restricted or prohibited.
marine snow
Organic particles, often plankton, that fall into the deep sea from the sunlit surface waters.
meter
A length of measurement equal to 39.37 inches, or about three feet.
midwater
A marine habitat usually defined as the area between surface waters and the deeper waters nearer to the seafloor.
mollusk
Any of numerous chiefly marine invertebrates of the phylum Mollusca, typically having a soft unsegmented body, a mantle, and a hard, protective shell and including the edible shellfish and the snails.
moratorium
A mandatory cessation of fishing activities on a species (e.g. the blue whale), in an area (e.g. a sanctuary), with a particular gear (e.g. large scale driftnets), and for a specified period of time (temporary, definitive, seasonal, or related to re-opening criteria).
natural mortality
Deaths of fish from all causes except fishing (e.g. Ageing, predation , cannibalism, disease and perhaps increasingly pollution).
oceanography
The scientific study of all aspects of the physics, chemistry, geology and biology of the world's oceans.
offshore fish farms
Aquaculture operations located beyond three miles of a coastline, often involving submerged netcages anchored to the seafloor.
open access
A type of fishery that does not restrict how many fishermen or how many vessels participate.
overfishing
In general, action of exerting a fishing pressure (fishing intensity) beyond agreed optimum level. A reduction of fishing pressure would, in the medium term, lead to an increase in the total catch.
open netpen or netcage
Floating complexes of cages that confine farmed fish. The nets that comprise the walls and floors of the cages allow the free exchange of both water and wastes. The pens are at times covered by additional nets to prevent predation by birds or fortified to prevent predation by sea lions.
omnivore
An animal that feeds on both animal and vegetable substances. Catfish are a good example.
orange roughy
A bright orange fish that lives in the deep sea near Australia and New Zealand. Orange roughy grow very slowly--the orange roughy sold in markets may be 50 to 80 years old.
organism
A living thing – a plant, animal, bacterium or other life form.
organic
From a living thing or organism; originating in nature rather than being made artificially.
overfishing
Catching too many fish; fishing so much that the fish cannot sustain their population. The fish get fewer and fewer, until finally there are none to catch.
purse seine
A type of fishing net used to surround and catch large schools of fish. The net (or seine) is pulled in a circle to surround the school then drawn shut at top and bottom, much like a purse.
plankton
Plants and animals (mostly tiny) that swim weakly, or not at all, and drift with ocean currents. Plankton are an important food source for many fish and other organisms that live in the sea.
pollock
A fish related to cod, heavily fished by people for food. Pollock are made into fish sticks and imitation crab meat.
pollution
Degradation of the natural environment by chemicals, oil, trash or other substances.
polyculture
A system of pond aquaculture in which more than one species is raised. In China a type of polyculture has been developed over 4000 years in which different species of carp inhabit separate niches within the pond ecosystem, with beneficial results.
populations
A group of interbreeding organisms that represents the level of organization at which speciation begins. Population is measured as the total number of individuals of the species
predator
An animal that kills and eats other animals.
public hearing
A meeting to discuss or resolve an issue. The general population is invited.
reef
An underwater structure; something that extends up from the seafloor but does not rise above the surface of the water like an island. Coral reefs are formed from the hard skeletons of coral. There are also rocky reefs, which are piles of rock under water.
regulation
A rule adopted by a federal or state government executive branch agency. A regulation is based on and carries out a law.
replenishment
The process of moving or re-supplying fish stocks from a reserve storage location to a primary location
runoff
Polluted water that runs from the land or escapes from a pond into a larger body of water.
salinity
A measure of the salt content of water; sea water is approximately 3.5 percent salt.
Salmofan™
The Salmofan™ is a color scale designed to help the salmon farming industry visually determine the flesh color of salmon. It looks similar to a fan deck of paint colors. The farmed salmon are fed food pellets containing either synthetically produced or naturally derived pigments that are designed to give the flesh of farmed fish a look similar to the wild salmon. If colorants weren't used, the flesh of most farmed salmon would be more of a gray hue.
salmon
A family of anadromous fishes that breed in rivers but live most of their adult lives at sea. Salmon have orange or pink flesh. For centuries, salmon have been important food fish to people of many nations. When they're ready to breed, most salmon find their way from the ocean back to the same stream where they were born.
salmon run
A population of salmon that breeds in a certain river. Some rivers have several different runs of salmon that breed at different times of the year.
scarcity
Insufficient supply or amount of fish, a shortage of fish.
sea lice
A naturally occurring seawater parasite. High stocking densities make fish farms ideal breeding grounds for sea lice, and can drastically increase the number of lice in surrounding waters. One or two sea lice may be enough to kill a juvenile pink salmon newly arrived in saltwater.
silt
Substrate particles smaller than sand and larger than clay.
shrimp
Any of various small, chiefly marine decapod crustaceans, many of which are edible. The larger kinds are called also prawns. Shrimp are carnivorous. In Thailand the most commonly farmed species are black tiger shrimp (Penaeus monodon). Some other species of shrimp, including Pacific white shrimp (Litopenaeus vannamei) and some freshwater species are being bred to be more disease resistant.
smolt
An adolescent salmon which has metamorphosed and which is found on its way downstream toward the sea.
sonar
A system that uses transmitted and reflected sound waves to find objects under water.
spawn
To breed; especially, to breed by releasing eggs and sperm into the water.
species
A particular type of plant or animal. Plants and animals can breed only with members of their own species. In biology, species is a category that's part of the scientific system for grouping together related plants, animals and other organisms (kingdom, phylum, class, order, family, genus, species). Species is the most specific category.
stocks
The part of a fish population which is under consideration from the point of view of actual or potential utilization.
stocking density
The number or biomass of fish stocked per unit area or volume, such as in a pond or net pen.
sustainability
Meeting the needs of the present without compromising the ability of future generations to meet their own needs, or the health of the planet.
Sustainable Fisheries Act
The 1996 amendments to the Magnuson-Stevens Fishery Conservation and Management Act that imposed new requirements for federal fishery managers to prevent overfishing, rebuild overfished stocks, reduce bycatch, and protect essential fish habitats.
sustainable fishery
A fishery that is managed so that it can continue long-term, into the future without depleting either the targeted fish or other marine resources.
swordfish
A large predatory fish with a long, sword-like bill at the tip of its snout. Swordfish are famous for their speed, strength and trans-ocean migrations. They are heavily fished and many populations are vulnerable to over-fishing.
tilapia
Any of various cichlid fishes of the genus Tilapia, native to Africa's Nile River but introduced elsewhere as a valuable food fish. Some historians believe that tilapia were the fish that Jesus fed to the multitudes in the Biblical account. These omnivorous fish have been bred to require minimal amounts of fishmeal and fish oil.
tragedy of the commons
A metaphor used to illustrate the conflict between individual interests and the common good. The term was popularized by Garrett Hardin in his 1968 Science article "The Tragedy of the Commons."
transgenic fish
Fish that have been genetically modified.
trawl
A funnel-shaped net towed through the ocean or along the seafloor to collect fishes and invertebrates.
Trawl nets
A conical fishnet dragged through the water or, in the case of bottom trawl, along the seafloor. This is one of the most destructive types of fishing equipment.
trawler
A fishing boat that tows a trawl net.
trawling
Fishing by towing a trawl net.
upwelling
The movement of cold, nutrient-rich water from the ocean depths up toward the ocean surface.
vertical migration
An aquatic animal's daily or seasonal movement up toward the water's surface and back down to deeper water.
waterman
Someone who drives or rides in a boat, including both commercial and recreational fisherpeople.
white spot virus
One of many shrimp diseases that plagues the shrimp aquaculture industry. High stocking densities on farms often create crowded conditions that stress animals and make them more susceptible to viral and bacterial diseases.
yellowfin tuna
One of the larger species of tuna, which has yellow markings on its fins and tail. Yellowfin live in warm, tropical waters. Much of the world's canned tuna is yellowfin.
zooplankton
Animal plankton.
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