Anadromous-Species That Reproduce in and Inhabit Fresh Water, but Usually Journey out to the Ocean (Often Thousands of Miles) Be

Home , Feeding frenzy

Abundance index —a quantitative measure of fish density or abundance, usually as a time series. An abundance index can be specific to an area or to a segment of the population (eg large fish), or it can refer to abundance stock-wide; the index can reflect abundance in numbers or in weight (biomass).

Aerial survey —a method of gathering information on movements and density of fish near the surface by visual observation and photography from low-flying aircraft.

Age-structured assessment —an assessment of the status of a fish stock, based on the relative abundances of fish of different ages in the stock.

Ageing technique —a method of determining the ages of fish, most often done by counting daily or seasonal rings laid down in hard parts of the fish body, such as otoliths, scales or vertebrae.

Age–length composition (age–length key) —a table of the frequency of fish of each age in each length-group in a catch (or population) of fish. Tables of yearly age–length composition of catches provide the input for cohort analysis (see cohort analysis).

Age–length curve —a curve that shows the relation of length and age; it is a simplification of an age–length key.

Aggregation —a group (usually large) of fish of a single species that comes together to feed or spawn—or for other unknown reasons.

Albacore ( Thunnus alulunga )-a temperate tuna species widely distributed throughout the Pacific. Until the age of maturity (about 5 years) they are found in surface waters, where they are targeted by trolling. Some adult albacore are also caught using surface gears but, as a result of their deeper distribution, they are mainly caught using longlines.

Anadromous -Species that reproduce in and inhabit fresh water, but usually journey out to the ocean (often thousands of miles) before returning to spawn. They include salmon, steelhead trout, striped bass, Atlantic and shortnose sturgeons and some herring, although salmon is by far the most important commercially.

Aquaculture —the commercial growing of marine (mariculture) or freshwater animals and aquatic plants. Often termed ‘fish farming’ in relation to fish.

Archipelagic state-a State constituted wholly by one or more archipelagos and may include other islands. an archipelago as a group of islands, including parts of islands, inter-connecting waters and other natural features which are so closely inter-related that such islands, waters and other natural features form an intrinsic geographical, economic and political entity, or which historically have been regarded as such. These definitions do not include mainland States which possess non-coastal archipelagos, such as Denmark (with the Faroe Islands), Ecuador (with the Galapagos Islands) or Spain (with the Canary Islands) but would appear to embrace a number of States which would not normally consider themselves to be archipelagic States, such as Japan, New Zealand and the United Kingdom. Such States may draw straight archipelagic baselines which join the outermost points of the outermost islands and drying reefs of the archipelago

Archival tag —an implanted fish tag that detects and records (‘archives’) several environmental variables (for example, water temperature and pressure) over time. These tags give a unique record of the movements and behaviour of individual fish. Some tag types can transmit data to satellites.

Area closure —the closure of a fishing ground, or part of one, for a defined period of time; used as a tool in the management of a fishery.

Artisanal fishing —fishing for subsistence by coastal or island ethnic groups using traditional methods.

Bait net —a net used to catch bait fish for activities such as longlining and pole-and-line fishing.

Bigeye ( Thunnus obesus )-A widely-distributed species of tuna, ranging between 50 oN and 45oS. This species dwells in deeper water than other tunas and shows extensive vertical movements. Spawning occurs in tropical waters. From spawning grounds bigeye migrate into temperate water as they grow. Young fish associate with other tunas such as yellowtail and skipjack, often under FADs. This association weakens as they grow larger.

Billfish —marlins, sailfish, spearfish and swordfish; that is, fish where the snout is extended into a bill or ‘spear’.

Bimodal —see length–frequency distribution.

Biodiversity —biological diversity; variety among living organisms—including genetic diversity, diversity within and between species, and diversity within ecosystems (see also ecosystem).

Biological reference points (BRP) —indicators of the status of a stock; they provide a standard for comparison and are used as a fisheries management target . Reference points can be either ‘target reference points’ or minimum biologically acceptable limits (‘limit’ reference points). They are often based on fishing mortality rates or on the maintenance of adequate recruitment to the stock.

Biomass (B) —total weight of a stock or of a component of a stock; for example, the spawning biomass is the combined weight of mature animals.

BMSY -The level of biomass required to support the maximum sustainable yield. In some cases it refers to t he average stock biomass that results from taking an average catch of MSY under various types of harvest strategies. Often expressed in terms of spawning biomass, but may also be expressed as recruited or vulnerable biomass. B MSY is a common fisheries management limit or target.

Bo-The virgin biomass or the theoretical carrying capacity of the recruited or vulnerable biomass of a fish stock. In some cases it refers to the average biomass of the stock in the years before fishing started. More generally, it is the average over recent years of the biomass that theoretically would have occurred if the stock had never been fished. B 0 is often estimated from stock modelling and various percentages of it (e.g. 40% B 0) are used as BRPs to assess the relative status of a stock.

Biota —living things.

Biotoxins —natural toxins produced by organisms, often for defence.

Bycatch —species taken incidentally in a fishery where other species are the target. Some bycatch species are of lesser value than the target species, so are often discarded (‘trash’ species), but other bycatch species have some commercial value (‘byproduct’) and are retained for sale (see also non-target species). Broadbill swordfish (Xiphias gladius) -Oceanic, highly migratory, predatory fish characterized by a long, flat bill. Females grow larger than males, with males over 135 kg being rare. Females mature at 4-5 years of age while males mature first at about 3 to 4 years. Batch spawning occurs in water warmer than 24 °C year round in the equatorial Pacific. Adult swordfish forage includes pelagic fish including small tuna, flying fish, mackerel, as well as some benthic species. Squid are important when available. They are sought after commercially by surface longlines. Swordfish is a popular sport fish, though elusive.

Cage culture —a type of aquaculture in which fish are grown on in enclosures in open water; also referred to as fish farming or sea ranching.

Catchability —in a general sense, the extent to which a stock is susceptible to fishing; quantitatively, the proportion of the stock removed by one unit of fishing effort.

Catch-at-age data —data on the number of fish of each age group in the catch of a fishery, usually derived from the lengths of fish in representative samples of the catch.

Catch-at-length data —data on the number of fish of each length group in the catch of a fishery, usually obtained by measuring the lengths of fish in representative samples of the catch but occasionally derived from individual weights of fish.

Catch-at-weight data —data on the number of fish of each weight group in the catch of a fishery, usually obtained by measuring the individual weights of fish in representative samples of the catch.

Catch per unit of effort (CPUE) — The quantity of fish caught with one standard unit of fishing effort eg the number of fish taken per 1000 hooks per day; or the weight of fish taken per hour of trawling. CPUE is often assumed to be an abundance index. A declining CPUE may mean that more effort eg metres of net set and/or length of soak time, is required to catch a given volume of fish. This in turn may indicate that a fish stock has declined (although other factors can also influence rates of CPUE, particularly for species that have patchy or clumped distributions).

Catch rate —see catch per unit of effort.

Cohort —those individuals of a stock born in the same spawning season. For annual spawners, a year’s recruitment of new individuals to a stock is a single cohort or year- class.

Cohort analysis —a technique for estimating the magnitude of fishing mortality and the number of fish at each age in a stock by tracing the history of the cohorts.

Commercial value —the value of landings to commercial fishers.

Conspecific —individuals that are members of the same species.

Continental shelf —seabed from the shore to the edge of the continental slope.

Continental slope —region of the outer edge of a continent between the generally shallow continental shelf and the deep-ocean floor, usually demarcated from the shelf by the 200 m isobath.

Cottage industry —small, locally owned businesses usually associated with low relative yield and limited technology. D

Decision rules —agreed responses that management must make under pre-defined circumstances regarding stock status.

Depletion (stock depletion) —reducing the biomass of a fish stock through fishing.

Development (of fisheries) —transition from exploratory and experimental fishing to the establishment of commercial activities and markets, with the ultimate goal of sustained long-term fishing; cf. ecologically sustainable development.

Discarding —a less emotive description for the disposal (or ‘dumping’ or ‘trashing’) of unsaleable catch, dead or alive, during or after fishing operations (see also bycatch, non- target species).

Domestic fishery —a fishery within the Australian Fishing Zone operated by Australian- flagged vessels.

Dressed-weight —weight of the carcass after processing (e.g. gills and viscera removed). Driftnet—a gillnet suspended by floats so that it fishes the top few metres of the water column.

Ecologically sustainable development —using, conserving and enhancing the community’s resources so that ecological processes, on which life depends, are maintained, and the total quality of life, now and in the future, can be increased.

Ecosystem—a complex of plant, animal and micro-organism communities that, together with the non-living components, interact to maintain a functional unit.

Effort —see fishing effort.

Effort restriction —a type of input control used as a management tool, it restricts the amount of fishing effort (for example, trawl hours) expended by fishers in a particular fishery.

Egg survey —a systematic gathering of information on the occurrence and abundance of fish eggs and larvae by collecting them in nets and traps.

El Niño —Southern Oscillation episodes—large-scale, cyclical (3–7 years), warming and cooling episodes across the equatorial Pacific; warm water pools in the east during El Niño conditions and, conversely, in the west during ‘La Niña’ conditions.

Endangered species —under endangered species protection legislation, a species in danger of extinction because of its low numbers or degraded habitat; or a species likely to become so unless there is an improvement in the factors affecting its status (see also vulnerable species).

Endemic, endemism—so called ‘native species’, which are confined to a given region; for example, a species endemic to Australia is not found beyond Australia.

Epibenthos —invertebrate animals living on the surface of the seabed.

Epipelagic —associated with the surface layer of a water body; cf. pelagic. Exclusive Economic Zone (EEZ) —Exclusive Economic Zone defined in terms of a 200- nautical-mile zone under provisions of the United Nations Convention on the Law of the Sea.

Exploitation rate —the fraction of total animal (usually fish) deaths caused by fishing, usually expressed as an annual value. Exploitation rate can also be defined as the proportion of a population caught during a year.

Fecundity —number of eggs an animal produces each reproductive cycle; the potential reproductive capacity of an organism or population.

Finning-The practice of removing the fins and discarding the carcass, usually pertaining to sharks

Fish (fishes; finfish; scalefish) —literally, a vertebrate (animal with a backbone) that has gills and lives in water, but often used more broadly to include any harvestable animal living in water (‘fishes’ refers to more than one species of fish; ‘finfish’ refers to sharks, some rays, and bony fishes; and ‘scalefish’ refers to fish with scales).

Fish Aggregating Device (FAD) -Artificial or natural object placed on the sea surface to attract species sought underneath, thus increasing their catchability.

Fishing-down —a fish stock that has not been heavily fished may have a large number of older fish. When such stocks are fished, catches are highest at first, but the rate cannot be sustained once the abundance of older fish has been reduced. Removing the older fish in this way is termed fishing-down.

Fishery —a term used to describe the collective enterprise of taking fish. A fishery is usually defined by a combination of the species caught (one or several), the gear and/or fishing methods used, and the area of operation.

Fishery-independent survey —a systematic survey carried out by research vessels or contracted commercial fishing vessels for the purpose of gathering information independent of normal commercial fishing operations.

Fishing capacity —the total fishing effort that can be expended by the fleet operating in a fishery.

Fishing effort —amount of fishing taking place, usually described in terms of gear type and frequency or period during which the gear is in use; for example, ‘hook-sets’, ‘trawl- hours’, ‘searching hours’.

Fishing mortality (F)—the rate of deaths of fish due to fishing. The rate indicates the percentage of the population caught in a year; for example, a fishing mortality rate of 0.3 implies that e-0.3 of the population—about 35%—is being removed in a year by fishing (see also mortality, natural mortality).

Fmax –A reference point defined by t he rate of fishing mortality for a given exploitation pattern rate of growth and natural mortality, that results in the maximum level of yield- per-recruit. This is the point that defines growth overfishing.

F0.1 -A reference point defined by t he fishing mortality rate at which the increase in yield-per-recruit in weight for an increase in a unit-of-effort is only 10 percent of the yield- per-recruit produced by the first unit of effort on the unexploited stock (i.e., the slope of the yield-per-recruit curve for the F0.1 rate is only one-tenth the slope of the curve at its origin). Fishing power —the effectiveness of a vessel’s fishing effort relative to the effectiveness of other vessels’.

Fishmeal —protein-rich animal feed made of fish or fish waste.

Flag-of-convenience —the registration of a ship to a country other than the country of ownership.

Fork length (FL) —the length of a fish measured* as the distance between the tip of the snout and the most anterior point of the fork or ‘V’ of the tail. This is the measure commonly used for the recording length of commercial fish species because it is usually little-affected by damage to the tail fin; c.f. total length. * From point to point—not, for example, by laying a tape along the body surface, which would result in a longer measurement for full-bodied fish like tuna .

Free school – aggregation of fish made up entirely of the same species

Front (temperature front; frontal region) —region where a sharp gradient in temperature occurs, often indicating the demarcation between two current systems or water masses; usually associated with intense biological activity.

Fully fished —describes a fish stock for which current catches and fishing pressure are close to optimum (the definition of which may vary between fisheries; for example, catches are close to maximum sustainable yield). Categorising a species as ‘fully fished’ suggests that increasing fishing pressure or catches above optimum (allowing for annual variability) may lead to overfishing (see overfished).

Gamefish-fish pursued for sport by recreational anglers

Gear restriction —a type of input control used as a management tool to restrict the amount and/or type of fishing gear that can be used by fishers in a particular fishery.

Ghost fishing —where lost gear, usually nets or traps, continues to capture and kill fish.

Gillnet, monofilament gillnet —a type of passive fishing gear consisting of panels of net held vertically in the water column, either in contact with the seabed or suspended from the sea surface, such that fish attempting to swim through the net are entangled. The mesh size of the net determines the size range of fish caught, as smaller fish can swim through the meshes and larger fish are not enmeshed (see also driftnet).

Global positioning system (GPS) —a device that uses satellite signals to determine a vessel’s position and course accurately.

‘Grow-out’ ponds —ponds that are used to hold hatchery-reared or wild-gathered stock until they reach the desired marketable size.

Growth model —mathematical description or representation of the rate at which a species grows at different sizes or ages.

Growth overfishing —occurs when too many small fish are being harvested; a restraint on catching them would result in an overall increase in yield from the fishery.

Handline —hand-held lines of various types that are used to catch fish. Harvest strategy —well-managed fisheries have an unambiguous (explicit and quantitative) harvest strategy, robust to the unpredictable biological fluctuations to which the stock may be subject. It states how the catch will be adjusted from year to year depending on: the size of the stock, the economic or social conditions of the fishery, conditions of other interdependent stocks, and the uncertainty regarding biological knowledge of the stock.

High Seas —waters outside national jurisdictions, areas encompassing high seas are sometimes called high seas pockets.

Highly migratory species (HMS) - derives from Article 64 of the United Nations Convention on the Law of the Sea. Although the Convention does not provide an operational definition of the term, an annex to it lists species considered highly migratory by parties to the Convention (for the list of species see annex 1a in the Supporting information (Highly Migratory Species)). This list is further specified in Schedule 4B of the Fisheries Act 1996 (see annex 1b in the Supporting information (Highly Migratory Species)). In general, these species are pelagic, have a wide geographic distribution, both inside and outside countries' EEZs, and undertake migrations of significant but variable distances across oceans for feeding or reproduction.

Impoundment —any enclosure or facility used to restrict the movement of fish stocks, whether in natural or artificial environments.

Incidental catch —see bycatch.

Index of abundance —a relative measure of the abundance of a stock; for example, catch per unit of effort.

Individual transferable quota (ITQ) —a management tool by which portions of the total available catch quota are allocated to individual fishers or companies. These individuals or companies have long-term rights over this quota but can trade quota with others (see also quota).

Input controls —indirect restraints placed by management to reduce the amount of fish caught; for example, gear restrictions, closed seasons; cf. output controls (see also limited entry fishery).

Inshore waters —waters of the shallower part of the continental shelf; cf. nearshore waters.

Invertebrates —animals without a backbone; for example, shellfish, worms, jellyfish, sponges, seastars and corals; cf. vertebrates.

Isobath —contour line linking regions of the same depth.

Isotherm—contour line linking regions of the same temperature.

Jig —to fish with lures on a vertical line that is moved up and down, or jigged. Jigging is done with hand-operated spools or automatic machines, as in the southeastern Australia fisheries for arrow squid.

Joint venture —collaborative fishing operation, usually involving two companies from different countries.

L Landings-The part of the catch that is landed.

La Niña —an oceanographic condition involving excessive pooling of cool waters in the equatorial Eastern Pacific Ocean (see also El Nino – Southern Oscillation episodes).

Latent effort —fishing capacity that is authorised for use but not currently being used.

Length–frequency distribution [modal size] —the number of individuals in a catch or catch sample in each group of lengths (length intervals). The modal size is the length group into which most individuals fall. Some distributions may show several modes, reflecting fish of different ages.

Limited-entry fishery —a fishery where the fishing effort is controlled by restricting the number of operators. It usually requires controlling the number and size of vessels, the transfer of fishing rights, and the replacement of vessels; cf. open-access fishery.

Line fishing —a general term for a variety of fishing methods that use fishing lines in one form or another. It includes handlines, hand reels, powered reels, pole-and-line, droplines, longlines, trotlines and troll lines.

Logbook —an official record of catch and effort data made by fishers. In many fisheries, a licence condition makes the return of logbooks mandatory.

Long-term potential yield —an estimate of the largest annual harvest that could be taken from a fish stock on a sustainable basis, allowing for variable environmental conditions. This may be estimated in various ways, ranging from taking an average of a time-series of historical catches to using sophisticated mathematical models.

Longline —a fishing gear in which short lines (‘droppers’) carrying hooks are attached to a longer main line at regular intervals. Pelagic longlines are suspended horizontally at a predetermined depth with the help of surface floats. The main lines can be as long as 100 km and have several thousand hooks. Droppers on demersal longlines (set at the seabed with weights) are usually more closely spaced.

Mariculture —fish farming or aquaculture of marine animals or plants.

Market niche —a small gap in a market, that could be filled by a particular enterprise.

Maximum constant yield (MCY) —a different approach to maximum sustainable yield; the maximum constant catch sustainable for all probable future levels of stock biomass (see also long-term potential yield). In contrast, a larger long-term average catch would be achieved were the catch adjusted each year to take account of stock increases and decreases because of environmental variability.

Maximum sustainable yield (MSY) —can be defined in various ways, but originated from surplus-production models as the maximum catch that can be removed from a stock over an indefinite period without affecting sustainability. MSY defined in this way makes no allowance for environmental variability, and studies have demonstrated that fishing at the level of MSY is often not sustainable (cf. longterm potential yield).

Medina panel–a panel of relatively small mesh sewn into a purse seine designed to protect marine mammals such as dolphins from becoming entangled.

Migration —non-random movement of individuals of a stock from one place to another, often moving in groups. Minimum size —by law, no individual smaller than the size prescribed for its species is allowed to be retained.

Model (population) —hypothesis of how a population functions; often uses mathematical descriptions of growth, recruitment and mortality.

Mode; modal size —see length–frequency distribution.

Morphology —the study of the form and shape of animals and plants.

Morphometrics —the form and shape of an animal. Differences in morphometrics are often used to distinguish different stocks of the same species.

Mortality —rate of deaths (usually in terms of proportion of the stock dying annually) from various causes (see also natural mortality, fishing mortality).

Multifan-CL -A stock assessment model based on length-based separable models and tuning of abundance indices. The population model is length/age-structured.

National jurisdiction-a nation possesses supreme authority, or sovereignty (called jurisdiction), over all territory, things, and persons within its boundaries. It may also exercise jurisdiction over its own property and its nationals and their property in foreign jurisdictions, subject to the jurisdiction of other nations as set forth in international law or treaties.

Natural mortality (M) —deaths of fish from all causes except fishing. It is often expressed as a rate that indicates the percentage of fish dying in a year; for example, a natural mortality rate of 0.2 implies that e-0.2 of the population—about 22%—will die in a year from causes other than fishing.

Nautical mile (n.mile) —unit of distance equivalent to 1 minute of the great circle of earth (= 1.852 km).

Nearshore waters —shallow inshore waters.

Neritic zone —the shallow pelagic zone over the continental shelf.

Non-target species —species that are unintentionally taken by a fishery or not routinely assessed for fisheries management (see also bycatch).

Not overfished —see overfished.

NPOA —Seabirds -National Plan of Action to Reduce the Incidental Catch of Seabirds in New Zealand Fisheries

NPOA —Sharks-National Plan of Action for the Conservation and Management of Sharks

Nutrient upwelling —divergence of water currents or movement of the surface water away from land can lead to a ‘welling-up’ of deeper water that is usually richer in nutrients than the surface water.

Observer data —fisheries information collected on fishing vessels by independent observers. Oceanic —to do with the open-ocean waters beyond the edge of the continental shelf.

Offshore waters —usually refers to the more oceanic waters, though can refer to outer continental shelf waters; cf. onshore waters.

Onshore waters —waters abutting the coastline; cf. nearshore waters.

Open-access fishery —fishery in which there is no limit on the number of operators or vessels; cf. limited-entry fishery.

Otoliths —bones formed in the inner ear of fish. The rings or layers can be seen in the entire or sectioned otolith, and counted to determine age.

Output controls —management measures directly limiting fish catch or landings (for example, by quota); cf. input controls.

Overfished —a fish stock with a biomass below a prescribed threshold or limit reference.

Overfishing —the amount of fishing that exceeds a prescribed level or limit reference.

Oxy-tetracycline (OTC) —an antibiotic injected in a fish to leave a mark on skeletal structures, such as otoliths. When the fish is later recaptured, the mark left by the OTC can be used to validate age estimates, as the date of injection is known.

Parameter —characteristic feature or measure of some aspect of a stock, usually expressed as a numerical value; for example, see natural mortality.

Parental biomass —the weight of the adult population of a species; for example, if southern bluefin tuna mature at eight years of age, the weight of all southern bluefin eight years and older (see also spawning biomass).

Pelagic —inhabiting surface waters rather than the sea floor. This term is usually applied to free-swimming species such as tunas and sharks; cf. demersal and epipelagic.

Pole-and-line fishing (poling) —also called pole-and-live-bait fishing, involves attracting schools of fish to the vessel with live or dead bait, then getting them into a feeding frenzy with more bait and water sprayed onto the sea surface to simulate the behaviour of small bait fish. Fishers use a pole with a short, fixed line and lure, ‘poling’ the fish aboard.

Population structure —composition of a population in terms of size, stock (genetic or regional), age class, sex, etc.

Potential yield —see long-term potential yield.

Precautionary principle —where there are threats of serious irreversible environmental damage, lack of full scientific certainty should not be used as a reason for postponing measures to prevent environmental degradation. In the application of the precautionary principle, public and private decisions should be guided by: (i) careful evaluation to avoid, wherever practicable, serious or irreversible damage to the environment and; (ii) an assessment of the risk-weighted consequences of various options.

Productivity —when applied to fish stocks the term ‘productivity’ gives an indication of the birth, growth and death rates of a stock. A highly productive stock is characterised by high birth, growth and mortality rates, and can sustain high harvesting rates. Projection —with the help of a mathematical model as a numerical representation of the population, a prediction of what may happen in the future under a variety of conditions.

Purse seining —a fishing method capable of harvesting large quantities of surface- schooling pelagic fish by surrounding the school with a net. A line that passes through rings on the bottom of the net can be tightened to close the net so that the fish cannot escape.

Quota —amount of catch allocated to a fishery as a whole (total allowable catch) or to an individual fisher or company (see individual transferable quota).

Quota species —species for which catch quotas have been allocated.

Recovery plan —a recovery plan is a management process put in place to rebuild a stock when the measure of its status (e.g. its biomass) is below a defined limit (i.e. it is assessed as overfished). Recovery plans should include elements that define stock specific management objectives, harvesting strategies controlled by decision rules, and recovery periods.

Recreational-Refers to catch or effort that is exerted by sports fishers.

Recruit (recruitment) —usually, a fish that has just become susceptible to the fishery; for example, a recruit to the Australian southern bluefin tuna surface fishery is one to two years old, whereas a recruit to the Japanese longline fishery is three to four years old. Sometimes used in relation to population components; for example, a recruit to the spawning stock.

Recruitment overfishing —occurs when excessive fishing effort or catch reduces recruitment to the extent that the stock biomass falls below the pre-defined limit reference point.

Reference point —an indicator of the level of fishing (or stock size), used as a benchmark for assessment (see also biological reference points).

Relative abundance - An estimate of actual or absolute abundance, usually stated as some kind of index.

Resolution-A decision made by the Commission which is not binding.

Risk analysis —analysis that evaluates the possible outcomes of various harvesting strategies or management options.

Sashimi —Japanese dish of raw sliced fish.

School-A group of fish swimming together. Schools are often formed of fish of the same species and age and size. Some tuna fishing gear most notably purse seine is designed to target schools.

School sets-fishing effort exerted on schools not associated with floating objects or other animals. These may be free-swimming schools that are usually feeding on baitfish or schools associated with current interfaces or areas of upwelling. Seasonal closure —the closure of a fishing ground for a defined period of time, used as a tool by fishery managers, frequently to protect a stock during a spawning season.

Shelf break —region where the continental shelf and continental slope meet; that is, where the more gently sloping region of the seabed adjacent to a landmass rather abruptly slopes steeply down towards the ocean depths; commonly around depths of 200 m.

Shot-by-shot —pertaining to each separate deployment of a fishing gear by a fishing vessel.

Size-frequency —see length–frequency distribution.

Size-at-age —length or weight of fish at a particular age.

Size-at-first-maturity —length or weight of the fish when it attains reproductive maturity.

Slope (mid-slope; upper-slope) —continental slope. The more steeply dipping seafloor beyond the edge of the continental shelf.

Spawning-stock biomass —(also called spawning biomass) the total weight of all adult fish in a population.

Spawning-stock biomass per recruit (SSB/R) —the effective contribution to the stock’s spawning output that a recruit makes throughout its life. Each recruit must be able to replace itself to ensure sustainability. Analyses using the SSB/R approach attempt to determine critical levels of fishing effort above which sustainability is endangered.

Species —members of a species of plants or animals can breed with another member and produce fertile (capable of reproducing) offspring. In this way, a species maintains its ‘separateness’ from other species; for example, yellowfin tuna and bigeye tuna are two distinct tuna species, whereas the general term ‘tuna’ includes all tuna species.

Species group —group of similar species often difficult to differentiate without detailed examination.

Standard- Mandatory minimums of performance required to ensure outcomes are met. They are clear, specific, measurable statements of results (KPIs) for a fishery. The difference between a standard and a supporting outcome is one of degree rather than kind. In essence a standard is a supporting outcome that has been labelled as such, for the purpose of enabling it to be used in the (subsidiary) management activity occurring within fisheries, and other stock management, plans. Standards are grouped according to the type of component they relate to, namely: (1) management process standards; which will define minimum performance in respect of management activity; and (2) fisheries performance standards; which will define the necessary state or condition of the aquatic environment, including fish stocks, as well as the desirable human benefits.

Stock —For the purposes of the Fisheries Act 1996, a stock is any fish, aquatic life or seaweed of one or more species that are treated as a unit for the purposes of fisheries management. For the purposes of the Harvest Strategy Standard, a biological stock is a population of a given species that forms a reproductive unit and spawns little if at all with other units. However, there are many uncertainties in defining spatial and temporal geographical boundaries for such biological units that are compatible with established data collection systems. For this reason, the term “stock” is often synonymous with an assessment / management unit, even if there is migration or mixing of some components of the assessment/management unit between areas. Some species form a single stock (for example, southern bluefin tuna), while others form several stocks (for example, albacore tuna in the Pacific Ocean belong to separate northern Pacific and southern Pacific stocks). The impact of fishing on a species cannot be determined without knowledge of this stock structure. Stock-reduction analysis —an assessment method that estimates the biomass of a fish population from its catch history, information on the productivity of the species, and a timeseries of abundance indices such as catch per unit of effort.

Stock–recruitment relationship —the relationship between the size of the parental biomass and the number of recruits it generates. Determination of this relationship is difficult; it involves studying the population’s size–age composition, growth and mortality rates.

Straddling stock —a fishery term used to describe migratory species that spend part of their lifecycle in two or more jurisdictions; especially those that migrate between EEZs and the high seas.

Super seiner —a large purse seiner, usually more than 70 m long and equipped with considerable freezing and storage facilities, capable of undertaking extended transoceanic voyages for harvesting fish.

Surplus production —inherent productivity of a fish stock that can be harvested on a sustainable basis. Based on the theory that, at large stock size, rates of reproduction and stock increase are slowed by self-regulating mechanisms, and that the stock increases faster after removals, because the stock attempts to rebuild. In theory, fishing can be moderated to take advantage of the more productive rates of stock increase, provided it does not exceed the stock’s capacity to recover.

Surplus-production model —mathematical representation of the way a stock of fish responds to the removal of individuals (for example, by fishing).

Sustainable yield —catch that can be removed over an indefinite period without reducing the biomass of the stock. This could be either a constant yield from year to year, or a yield that fluctuates in response to changes in abundance.

Swordfish-See broadbill swordfish

Tagging —marking or attaching a tag to an animal so that it can be identified when recaptured; used to study fish growth, movement, migration, stock structure and size (see also archival tag).

Target fishing (targeting) —fishing selectively for particular species or sizes of fish.

Taxonomic group —an organism’s location in the biological classification system used to identify and group those with similar physical, chemical and/or structural composition.

Threat-abatement plan —a plan formalised under endangered species legislation to counter the effects of a listed key threatening process (see also key threatening process).

Tori line —a line with streamers, towed as a scaring device over the area behind a vessel where sinking baited hooks are within range of diving seabirds; attached to a tori pole (boom) at the vessel’s stern.

Total allowable catch (TAC) —for a fishery, a catch limit set as an output control on fishing;see output control.

Total length (TL) —the overall length of a fish, measured as the distance between the most forward point of the snout and the most rearward part of the tail; c.f. fork length.

Trigger points, trigger rates —not usually used as a criterion for overfishing, but to indicate the need for review of management. Trolling —a fishing method in which lines with baits or lures are dragged by a vessel at a speed of 2–10 knots. Trolling is used Australia-wide to catch such fish as Spanish mackerel, yellowtail kingfish and several tuna species.

Tropical fisheries —fisheries undertaken in equatorial regions of the world sometimes defined by lines of latitude eg those waters between 10 0North and 10 0south.

Unassociated school-see free school

Uncertain —a fish stock that might be not overfished, overfished, or subject to overfishing, but for which there is inadequate or inappropriate information to make a reliable assessment of its status.

Underfished —a fish stock that has potential to sustain catches higher than those currently taken. The classification is not applied to stocks where catches have been limited to enable the stock to rebuild (see overfished).

Vertebrates —animals with a backbone, including fish (sharks, rays and bony fish), amphibians, reptiles, birds and mammals; cf. invertebrates.

Vessel monitoring system (VMS) - As part of monitoring, control and surveillance (MCS) systems, the VMS is a vessel tracking system (usually satellite based) which provides management authorities with accurate information on fishing vessel position (and speed) at specific time intervals.

Virgin biomass —the biomass of a stock that has not been fished (also called the unfished or unexploited biomass).

Virtual population analysis —a mathematical modelling technique used in stock assessment, whereby the number of fish in each cohort is estimated from numbers in the next oldest or next youngest age group, adjusted for the changes due to fishing and natural mortality; see also cohort analysis.

Vulnerable species —under endangered species protection legislation, a species that within 25 years will become endangered unless mitigating action is taken; see also endangered species.

Year-class —individuals spawned in the same year (or spawning season when that spans the end of one year and the beginning of the next).

Yellowfin tuna-(Thunnus albacares) A cosmopolitan tuna species distributed mainly in the tropical and subtropical oceanic waters where they form large schools. Smaller fish form surface schools mixed with skipjack and young bigeye while larger fish are found in surface and sub-surface waters.

Yield —total weight of fish harvested from a fishery.

Yield-per-recruit analysis —analysis of how growth and natural mortality interact to determine the best size of animals to harvest; for example, it may be more beneficial economically for fish to be caught when they are young and plentiful, or when older and larger but reduced in numbers by natural causes. ACE-Annual catch entitlement (QMS term)

ALC-Automatic location communicator (see also VMS)

B- biomass

BRP- biological reverence point

CCM-Members, cooperating non-members and participating territories of RFMO

CMM-Conservation and management measure

CNM -Cooperating non-members of RFMO

CPUE-Catch per unit effort, catch rate or the number or weight of fish caught by a unit of fishing effort.

F- fishing mortality rate.

FAD- fish aggregating device.

FL- fork length

FOB-abbreviation for free on board

ITQ - Individual Transferable Quota (QMS term)

IUU -Illegal, Unregulated and Unreported fishing activity.

K- carrying capacity. The average stock size expected in the absence of fishing. Even without fishing the stock size varies through time in response to stochastic environmental conditions. See also Bo

L∞- asymptotic (maximum) length

LFR-Licensed fish receiver (QMS term)

M- natural mortality rate

MCS- Monitoring, Control and Surveillance

MSY -Maximum sustainable yield

NPOA -National plan of action: see NPOA-seabirds and NPOA-sharks

Q- catchability

R- intrinsic growth rate

RFMO -Regional fisheries management organisation

ROP- Regional observer program (of the WCPFC)

SSB - spawning stock biomass

TAC-Total allowable catch VMP -Vessel management plan

VMS-Vessel monitoring system using ALCs

WCPO-Western and central Pacific Ocean

Y/R- yield per recruit

Z- total fishing mortality rate

CCAMLR-Commission for the Conservation of Antarctic Marine Living Resources www.ccamlr.org/

CCSBT-Convention for the Conservation of Southern Bluefin tuna www.ccsbt.org/

CITES-Convention on International Trade in Endangered Species of Wild Fauna and Flora www.cites.org/

CMS -Convention on Migratory Species of Wild Animals www.cms.int/

COFI-The Committee on fisheries, United Nations www.fao.org/fishery/about/cofi/

CSIRO-Council of Scientific and Industrial research Organisation, Australia www.csiro.au/

DFO-Department of Fisheries and Oceans, Canada www.dfo-mpo.gc.ca/

EU-European Union www.eurunion.org/

FAO-Food and Agriculture Organization www.fao.org/fishery/

FFA -Forum Fisheries Agency Pacific Islands www.ffa.int/

IATTC-Inter-American Tropical Tuna Commission www.iattc.org /

ICCAT-International Commission for the Conservation of Atlantic Tunas

ICES-International Council for the Exploration of the Seas www.ices.dk/

IOTC -Indian Ocean Tuna Commission www.iotc.org/

NGOs - Non-governmental organisations (here, generally with an environmental focus)

NIWA-National Institute of Water and Atmospheric Science, NZ

NRIFS F-National Research Institute of Far Seas Fisheries, Japan

NMFS-National Marine Fisheries Service, USA

NZBGFC -New Zealand Big Game Fishing Council

NZRFC - New Zealand Recreational Fishing Council

SPC-Secretariat of the Pacific Community TCC-Technical and Compliance Committee (of the WCPFC)

WCPFC-Western and Central Pacific Fisheries Committee