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Glossary

Action that helps society to cope with the effects of climate change

Acoustic Doppler Current Profiler (ADCP). A type of sonar that measures water velocity for a range of depths.

Arm's-length body

Young salmonids, from hatching to end of dependence on yolk sac as primary source of nutrition, during which stage they remain within the gravel.

Fish, born in freshwater, that migrates to sea, to grow and mature, and then returns to fresh water as adult to spawn (e.g. salmon).

Annelida, a group of ringed or segmented worms including bristleworms, earthworms and leeches.

Resulting from human activity

A group of single-celled organisms with have no cell nucleus or any other organelles

Trawl in which the net is held open by a beam or spar, with a trawl head at each end. Used for catching flatfish.

The Belly is the body of the trawl, its main purpose is to hold the fish and to lead them into the cod end. The belly is held between the square and the lengtheners.

Organisms that live on, in or near the bottom of the sea or river.

A process involving the separation of CO2 from industrial and energy-related emissions, and its subsequent transport to long-term storage

Fish, born in the sea, that migrate to fresh water to grow and mature, and then returns to sea to spawn (e.g. eels)

Cephalopoda, a class of mollusca with well developed head and eyes, and a crown of mobile tentacles

A change in the average state of our climate and/or the variability of its properties.

threshold levels below which a spawning stock should not be permitted to fall

A small planktonic crustacean

A development stage of copepods which follows the nauplius stage. It is segmented with more than 3 pairs of appendages

UK Government Department of Energy and Climate Change www.decc.gov.uk

UK Government Department for Environment, Food and Rural Affairs. www.defra.gov.uk

living or found in the deepest part of a body of water

factors limiting the growth of a population which are dependent on the existing population density

UK Government Department for Transport www.dft.gov.uk

Migrating between fresh and salt water; subdivided into anadromous and catadromous types (q.v.)

Unwanted fish and other species that are caught in fishing nets and then thrown away.

Former UK Government Department for Trade and Industry. Replaced by the Department for Business, Enterprise and Regulatory Reform. www.berr.gov.uk

East Coast Regional Environmental Characterisation

A collection of organisms that share the same physical environment and the interaction and interdependent relationships between them.

Electronic Data Capture

The study of the movement of charged particles under the influence of current.

Enzyme-Linked Immunosorbent Assay

Salmon or sea trout that survive to spawn

European Union europa.eu

Containing cells where structures are enclosed within membranes, in particular a nucleus.

Euphausiacea, an order of planktonic shrimp-like crustaceans including krill

The undesirable disturbance to ecosystem health and water quality that arises from nutrient enrichment caused by man's activity

The term fixed engine is used as a generic descriptor of stationary fishing gears in the UK

Species of fish that have a flat body and both eyes on the same side of the body, includes plaice, sole, dab, turbot and brill

Young salmonids at stages from independence on yolk sac as primary source of nutrition up to dispersal from spawning

UK Governments Food Standards Agency. www.food.gov.uk

A fish of the family of Cod, includes haddock, and hake

A term sometimes used for salmon and all kinds of trout

Study of the physical features of the Earth's surface and their relation to its geological structures

Walls or compounds of netting are set out in a particular pattern so that fish are gilled tangled or trapped. The gears may be set anywhere between surface and seabed, and either anchored or allowed to drift freely

Geographical Information System

An adult salmon that has matured, or is about to mature, after just one winter at sea

A rule of thumb, simplification, or educated guess that reduces or limits the search for solutions in domains that are difficult and poorly understood. Unlike algorithms, heuristics do not guarantee optimal, or even feasible, solutions and are often used with no theoretical guarantee

is the average height (from wave crest to trough) of the one-third highest waves at a location during a wave measurement time period. It is a frequently used scientific, naval architecture, engineering, and operational planning wave parameter. Individual wave heights vary, so that a statistical description, such as significant wave height, is used to define wave heights over a time period

The Inter-Agency Committee on Marine Science and Technology

International Council for the Exploration of the Sea. www.ices.dk

The intentional (or accidental) transportation and release by man of species or races into an environment outside their natural geographic range (see also reintroduction)

The World Conservation Union. www.iucn.org

Joint Nature Conservation Committee jncc.defra.gov.uk

A salmon that has spawned up until the time when it returns to the sea

Two pieces of netting which are joined along the sides to increase the trawl length between the belly and the cod end

UK Governments Ministry of Agriculture, Fisheries and Food. This has been replaced by Defra

the height above a fixed datum of the average water level over the sampling period

Animal life that is found on the bed of a river, lake, or sea thats small size means it is only just visible to the naked eye. Mobile benthic invertebrates that pass through a 42 or 63 micron mesh and are retained on a 500 micron mesh

Action that will reduce human-induced climate change

A salmon that has spent two or more winters at sea before returning to fresh water to spawn

is a field of applied science and technology covering a very broad range of topics. The main unifying theme is the control of matter on a scale smaller than one micrometere. Nanotechnology cuts across many disciplines, including colloidal science, chemistry applied physics and biology. The impetus for nanotechnology has stemmed from a renewed interest in colloidal science, coupled with a new generation of analytical tools. Despite the great promise of numerous nanotechnologies such as quantum dots and nanotubes, real applications that have moved out of the lab and into the marketplace have mainly utilised colloidal nanoparticles in bulk form in products such as sunscreens, cosmetics, and protective coatings such as stain resistant clothing.

Plural of nauplius, an early larval stage of many crustacean species. It is oval and unsegmented with 3 pairs of appendages

The North East Atlantic Fisheries Commission. www.neafc.org

A species of lobster, commonly called the Norwegian lobster or Dublin Bay Prawn/Scampi

Natural Environment Research Council. www.nerc.ac.uk

The National Federation of Fishermen's Organisation. www.nffo.org.uk

Oslo and Paris Commission www.ospar.org

A calcified structure used as part of the balance system in bony fishes. The mineral structure changes over time and annual banding can be seen in the otolith allowing scientists to estimate the age of a fish. More Information

A trawl held open horizontally by otter boards

Young salmonid, in the stage from dispersal from the redd until its migration as a smolt or for non-migratory forms until if becomes an adult

The mean direction at Tpeak

The upper layers of a body of water

Princeton Ocean Model

Young salmon, at the stage from leaving the river until the end of its first winter in the sea

The number of new juvenile fish reaching a size where they come large enough to catch via commercial fishing methods

The depression made in the gravel on the river bed by a female salmonid and in which her eggs are laid

Energy from sources that are, for practical purposes, inexhaustible such as wind, wave and tidal power

Opposite to flatfish. Fish that have eyes on opposite sides of its body, includes cod, whiting, anglerfish, haddock and hake

The time of year in which salmon or sea trout first return to fresh water and move up river

A fish belonging to the family Salmonidae, which includes the Atlantic salmon (Salmo salar), trout (Salmo trutta), charr (Salvelinus alpinus) and rainbow trout (Oncorhynchus mykiss)

Diadromous (migrating between fresh and salt water) form of the trout (Salmo trutta) after the post-smolt stage

The number of winters that a salmon has spent at sea

This is a bottom fishing method where fish are surrounded by warps laid out on the seabed with a trawl shaped net at mid lengths. As the warps are pulled in the fish are herded into the path of the net and caught

Any biological species that defines a trait or characteristic of the environment. For example, a species may indicate an environmental condition such as a disease outbreak, pollution, species competition or climate change. These species can be among the most sensitive species in a region, and sometimes act as an early warning to monitoring biologists.

Any species in the order Rajiformes. Although the English names for some skates refer to them as rays, the term 'ray' should refer to stingrays (Myliobatiformes) and electric rays (Torpediniformes)

Fully silvered juvenile salmon or trout migrating within a river system river or about to enter the sea

An estimate of the total weight of fish from a given stock which are involved in the spawning process at spawning time. It is derived from estimates of numbers of fish at each age in the stock at spawning time, multiplied by the proportion mature at each age, and finally multiplied by the estimated average weight of an individual fish at each age

A device for measuring and recording the intensity of various wavelengths in a spectrum of light.

the directional spread at Tpeak

Multi-sea-winter salmon which return to rivers early in the year, usually before the end of May

The square is a single sheet of netting which joins the belly and the top wings and acts as a cover to prevent the fish from escaping the path of the trawl by swimming upwards clear of the net

The first free-feeding stage newly emerged from the gravel

There are two top wings to a trawl which are tapered along the half mesh on the inside selvedge and straight along the outer edge.  They have a dual purpose as they act as a side wall of the trawl and also additional fore cover joined to the square

Dominant wave period, also called peak wave period, is the reciprocal of the center frequency of the frequency band that has the largest energy. Dominant wave period corresponds to the period of the larger waves that occurred during the measurement time period

The average or mean wave period that is also called the zero-crossing wave period.

The wave direction convention defines wave direction as the direction from which waves come measured clockwise from magnetic north. Magnetic north is used instead of true north so that users can collect and process directional wave data without entering magnetic corrections before every deployment to account for local variations of the earth's magnetic field. Corrections can be made after data collection and analysis to interpret wave directions in terms of true north

Rural Affairs Department www.wales.gov.uk / www.cymru.gov.uk

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Last Modified: 24 June 2011