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sea fisheries

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Common Fishery Terms Explained

Active Gears
Include trawls and seines which move through the water and herd or surround the fish
Benthic Species
Live on the sea bottom e.g. flatfish, nephrops
Size of a fish stock
Black fish
Fish landed illegally at night or in small unregulated harbours and not recorded against quota
Biomass Limit (BLIM)
Stock size below which the stock is in serious danger of collapse
Biomass Maximum Sustainable Yield (BMSY)
The population size of a fish stock when it reaches the maximum growth rate
An organism that is caught in addition to the target fish. Includes fish, turtles, marine mammals, seabirds & undersized fish. Some by-catches are marketable but most are discarded.   
Choke Species
A term used to describe a low volume quota species which, if reached, would lead to vessels having to tie up even if they still had quota for other species
Cod Catch Quota Scheme (CCQS)
In 2010 Marine Scotland and Defra introduced a voluntary pilot Cod Catch Quota Scheme (CCQS), where participating vessels must retain on board and land all cod that is caught, regardless of size and marketability. In return participating vessels are granted extra cod quota and fishing effort. 
Cod Recovery Plan (CRP)
Originally introduced by the Commission to increase the biomass of cod, its focus is now on reducing fishing to sustainable levels
Cod Recovery Zone (CRZ)
Area to which the Cod Recovery Plan applies
Common Fisheries Policy (CFP)
A policy agreed by the EU that details conservation of marine resources and the management of fisheries and fishing fleets
Deep Water Fisheries
Deep-water fisheries are defined as those that occur at depths of more than 400 metres
Demersal Species
Fish that live near or on the seabed. Includes species such as haddock, cod, whiting and flatfish.
De Minimis (DM) Exemption
An exemption applied where scientific evidence indicates that selectivity is very difficult to achieve or where the costs of handling unwanted catch are disproportionate
Fish thrown back into the sea after they are caught, which are usually dead. They are typically discarded because they are non-target species, below minimum landing size, above or below the ideal market size (high grading) or because the quota for that species has been exhausted. 
A combination of the time at sea and engine power of a fishing vessel. A reduction in fishing effort (effort control) can be achieved by limiting the time spent on fishing (days at sea).
Electronic Logbook
Software installed on board a vessel to record and submit data on fishing activities that is currently recorded in a paper logbook
Fishing Mortality
The rate at which fish are taken out of the sea by fishing activity
FMSY/Maximum Sustainable Yield
The highest yield which can be continuously taken from the stock under average conditions without significantly affecting the ability of that stock to reproduce
Gear Selectivity
Making fishing gear more selective (e.g. by reducing or increasing the net size) so that by-catch and discards are reduced. Gear selectivity can allow non-target species to be avoided or released unharmed.
Hague Preference
A mechanism designed to adjust national fish quota allocations to take account of the needs of certain fisheries-dependent areas in northern parts of the UK and in the Republic of Ireland. These arrangements can provide additional fishing opportunities to the UK and the Republic of Ireland, at the expense of other Member States when quotas for certain stocks fall below determined trigger levels.
High Survivability Exemption
An exemption which can be sought for a species where there is a high chance of survivability when released under certain conditions
International Council for the Exploration of the Seas (ICES)
An independent scientific advisory body which provides annual advice on fish stocks
Interspecies Flexibility (ISF)
Using quota of one stock to cover the catch of another stock
Juvenile Real Time Closures (JRTC)
Closing a sea area to fishing for a fixed period of time due to the high abundance of juvenile fish in the area
Low & Zero TAC
Stocks where the global TAC is set at 365 tonnes or below, and where no adjustment to relative stability will provide the Member States with enough quota to continue fishing at current levels and to meet the requirements of the Landing Obligation
Multi-Annual Plans (MAPs)
Set fishing mortality rates and potentially other management measures for a stock(s) for a set time
A Norwegian lobster; Dublin Bay prawn or langoustine
A ‘quick fix’ regulation which is making EU technical measures legally-compliant with the discard ban
Passive Gears
Include hooks, gill nets and traps which rely on the attraction or the natural movement of fish to make contact between fish and gear
Pelagic Species
Fish that live in mid-water or close to the surface. Includes species such as herring and mackerel.
Producer Organisation (PO)
Officially-recognised bodies who guide the activities of their members and try to align supply with demand and create added value for landed catch
Real Time Closures (RTC)
Temporary closure of a sea area due to a high abundance of cod
New, young fish which enter the stock and fishery
Relative Stability
A system which allocates TACs to Member States based on their historic fishing activity. In practice, this guarantees each Member State a fixed percentage of each and every TAC in the EU.
Spawning Stock Biomass (SSB)
The amount of fish in the stock (by weight) which can reproduce and contribute to the next generation of fish
Scientific, Technical & Economic Committee for Fisheries (STECF)
Official scientific advisers to the Commission
Scottish Conservation Credits Scheme (SCCS)
The SCCS rewards fishermen with additional days at sea when they sign up to initiatives which have an appreciable effect on the conservation of fragile fish stocks
Survivability Exemption
An exemption which allows fishermen to return to the sea their catch of a stock that has a scientifically-proved high chance of survival
Total Allowable Catch (TAC)
The total amount of fish allowed to be caught from a particular stock over a specified period of time. TACs are negotiated between the Commission and the European Council once a year, or fixed for several years by long-term management plans. 
Total Stock Biomass
The whole stock, including immature fish
Vessel Monitoring System (VMS)
VMS is a form of satellite tracking system using transmitters on board fishing vessels. The system is a legal requirement under EC Regulation No. 2244/2003 and Scottish SI No. 392/2004.