Sustainable Seafood Glossary

These terms relate to our Sustainable Seafood policies and practices:

  • Aquaculture/Fish Farming: The rearing of aquatic animals or cultivation of aquatic plants for food in salt, brackish or fresh water. This form of production accounts for about half of the seafood produced globally.
  • Bioaccumulation: The accumulation of substances or chemicals in the food chain at a rate than can be neutralized. This often affects high-order species in the chain, such as tuna, and is the mechanism behind higher mercury levels in some fish. 
  • Biomass: The total weight of a fish species in a given area.
  • Bird Scare Lines:  Lines or streamers used to minimize the bycatch of sea birds when setting and hauling longlines.
  • Bycatch: A fish or other marine species that is not the species being primarily targeted by a fisherman or fishing vessel, but which is caught. 
  • Dead Zones: Hypoxic (low-oxygen) areas in oceans and lakes around the world caused by excessive concentrations of nutrients due to human activities coupled with other factors. These zones are inhospitable to most marine life.
  • Dredge: A heavy mesh gear that is towed along the ocean floor by a boat in order to collect edible bottom-dwelling species.
  • Drift Net Fishing: : A fishing technique in which nets hang vertically due to floats at the top and weights on the bottom. They are not anchored to the water’s floor.
  • Ecosystem: A community of organisms interacting with each other and their environment such that nutrients cycle and energy flows throughout the system.
  • Effluent: The waste stream and material discharged from aquaculture or fish farming operations.
  • Feed Conversion Ratio: A measure of an animal’s efficiency in converting its feed into a desired output. In aquaculture, the lower the feed conversion ratio the better as it indicates less wild seafood protein is used to grow the farmed fish.
  • Fish Stock: A subpopulation of a species for which elements such as growth and mortality are significant factors in determining population dynamics, while factors such as immigration and emigration are ignored.
  • Fisheries Collapse: The result of overfishing and unsustainable fishing practices that occurs after a fish stock has been overfished to the point it cannot sustain itself and population levels experience a dramatic decline.
  • Fishery: A geographical area where fish are reared or caught for commercial purposes. 
  • Gillnet: A type of net in which a wall of netting hangs in the water column. The net’s mesh size is designed to allow fish to get only their head through, catching the gills in the mesh.  
  • Handline Fishing: A technique in which a single fishing line is held in hand and used to catch fish, as opposed to a pole or rod.
  • Hook-and-Line Fishing: A variety of methods that employ short fishing lines and hooks. 
  • Individual Fishing Quota (IFQ): A dedicated portion of a species-specific Total Allowable Catch that belongs to one individual or a group of fisherman – as a mechanism by which governments regulate fishing.
  • Individually Quick Frozen (IQF): Seafood or meat products that have been frozen separately from one another.
  • Illegal, Unreported and Unrequlated (IUU) Fishing: Fishing that often occurs in fisheries lacking strong management, often violating management measures such as IFQs and bycatch limits. This practice directly undermines conservation management around the world, compromising the sustainability of global fisheries.
  • Jig Fishing: A simple form of hook-and-line fishing, using vertical lines onto which baited hooks are attached.  
  • Landings: The total volume of fish harvested from the sea and successfully brought to land.
  • Longline: Lines with baited hooks connected to a main line at regular intervals. Longlines are generally used in deep-sea commercial fishing and can range in size from 25 to 2500 baited hooks.
  • Maximum Sustainable Yield (MSY): The largest theoretical amount of a population (fish or otherwise) that can be removed without impacting the productivity of future generations. 
  • Overfishing: When the amount of fish taken from a fishery is greater than the amount the remaining population is able to replenish, resulting in a net loss of fish.
  • Paralytic Shellfish Poisoning (PSP): A type of shellfish poisoning commonly associated with bivalve mollusks and other shellfish such as mussels, clams, crab and oysters. The result of algae blooms, it generally requires the closure of a fishery.
  • Pelagic fish: Fish that live in the ocean’s pelagic zones. There are two types of pelagic fish, those that live on the coast – “pelagic coastal fish” – and those that live in the open ocean – “oceanic pelagic fish.”
  • Pot/Trap Fishing: Using a device, usually a pot or trap, to catch fish. The traps are laid along the ocean floor and left for an extended period before being hauled out.
  • Purse Seine: A type of  that is deployed around an entire school or area of fish, encircling them and preventing escape; then hauled onto the shore or into a boat. Generally used on fish that school near the surface.
  • Raceway: A type of artificial channel used in aquaculture operations. Also referred to as flow-through systems.
  • Sustainable Seafood: Seafood that comes from sources, either wild-caught or farmed, that can increase or maintain production into the long term and do not compromise ecosystems impacted by fishing or farming practices.
  • Total Allowable Catch (TAC): A fishery management term that defines the total amount of a target species that can be taken out of a fish population in a given time period.
  • Trawl: A type of fishing gear that uses a wide-mouth net that tapers to a small end and is towed behind a fishing vessel at various depths.
  • Trolling: A type of hook-and-line fishing method where one or multiple unconnected lines with baited hooks are towed behind a fishing vessel.
  • Turtle Excluder Device (TED): A device used in trawl gear that allows a sea turtle captured in the gear to escape.
  • Well-Managed Fishery: A fishery that employs effective management measures that are successfully enforced.