Dictionary of Ichthyology
Brian W. Coad and Don E. McAllister†
N
N = number of fish studied; n is often used.
N = the letter represents a wriggling eel and in Phoenician and Hebrew is called nun (a fish).
n = 1) annual mortality rate (the ratio between the number of fish which die during a year from causes other than fishing and the number alive at the beginning of that year. Also called annual natural mortality rate, conditional natural mortality rate, seasonal natural mortality rate).
n = 2) number of fish studied; N is often used.
n = abbreviation for the haploid chromosome number.
n. = 1)abbreviation for nobis, meaning to us.
n. = 2) abbreviation for nomen, meaning name.
n. = 3)abbreviation for novus, meaning new.
n. = 4) abbreviation for nudum, meaning naked.
n.b. = nota bene, take notice, note well. Also NB.
n. g. = new genus.
n. n. = abbreviation for nomen novum, or new name; or nomen nudum.
n. nov. = abbreviation for nomen novum, or new name.
n. sp. = abbreviation for nova species, meaning new species.
n. v. = abbreviation for non visus, meaning not seen.
n-cut = a net cut at right angles to the general course of the netting. Also called point cut.
nabert = nebert.
nabby = a wooden club for killing salmon (Scottish dialect).
nadiral = lowest point or lowest side; occasionally used for the lower side in Pleuronectiformes.
NAFO = Northwest Atlantic Fisheries Organization, responsible for setting quotas for some stocks that are outside Canada’s 200-mile limit, straddle the line, or are of mainly foreign interest.
nail knot = the knot used to attach a leader to a fly line or to the butt section (q.v.) which rolls out well when casting. Can also be used or to attach line to hooks, swivels, snaps and lures where a double loop through the eye provides a cushion for extra knot strength. A nail or needle can be used to wrap the line around to facilitate tying this knot. Various websites have animated steps showing how to tie this knot.
nail knot loop = a form of nail knot used when attaching a large lure to heavy line. A normal nail knot will not allow the lure to swing freely. Various websites have animated steps showing how to tie this knot.
naïve = without prior exposure or experience, e.g. to a parasite.
naked = lacking scales.
naked name = nomen nudum.
nam pla = a pungent fish sauce from Thailand made from fermented anchovies.
namaribushi = small whole skipjack tuna, or chunks of bigger ones, boiled and then slowly roasted to remove some of the moisture (Japan).
name = nomenclaturally, the word or words that constitute the scientific designation of a taxon.
name, available = a scientific name of an animal satisfies the provisions of the International Code of Zoological Nomenclature, including publications of the name after 1757 in a latinized form or arbitrary combination of letters constructed so it can be treated as one, in a work consistently applying binomial nomenclature, not first published in a synonymy, etc.
name, invalid = any name for a given taxon other than the valid name, q.v.
name, preoccupied = one that is a junior homonym, a name with the same spelling that is erected anew for another taxon.
name, replacement = a new name (nomen novum) published or an available synonym adopted to replace an earlier name, and valid only if the latter is preoccupied; commonly applied to substitute names proposed to replace junior homonyms.
name, substitute = see name, replacement.
name, valid = the correct name for a given taxon; a taxon may have several available names; but only one of those names (most frequently the oldest) is the valid name.
name-bearing type = the type genus, type species, holotype, lectotype, series of syntypes (which, together, form the name-bearing type), neotype, type slide, or hapantotype, that provides the objective standard of reference whereby the application of the name of a taxon can be determined.
name-group = an assemblage of coordinate categories.
named fish = certain fish have been named individually for a variety or reasons: these include commerce, artistic need, entertainment, aquariology, etc. These are legion and the category "fictional fish" in Wikipedia gives an extensive list. See babel fish, Blinky, bubba, Charlie the Tuna, Clarissa, Nemo, etc.
nano cube = a small (under 30 gallons) marine aquarium, cheaper than larger ones but difficult to maintain and restricted in the fishes it will support. Also called nano reef. See also pico reef.
nano reef = nano cube.
nap = 1) knap (a shoal or bank on fishing grounds (Newfoundland)).
nap = 2) said of line which, when entangled on the bottom, is pulled taught and then let go suddenly, the recoil causing the hook to spring free (British dialect).
nape = 1) the region behind the back of the top of the head immediately posterior to the occiput.
nape = 2) the thickest part of a fish fillet, just behind the head on each side of the backbone, exposed on heading.
nape = 3) the flap at the end of cod's backbone after the head is removed and the fish split.
nape = 4) see also napes.
nape bone = the bone at the shoulder of a fish that forms the leading edge of a belly flap, q.v., in preparing fish as food. Also called collar bone, lug bone and shoulder bone.
nape cut fillet = a wide angular cut from the gill cover to the vent eliminating the rib cage, or by slicing it from the fillet.
nape fillet = boneless fillets with belly flaps removed.
napes = the belly wall of fish which appears as wings or flaps when the throat is cut and the belly split open.
naping = cutting through the head and belly as a preliminary to gutting a fish.
nare = sometimes used as the singular form of nares, the plural of naris.
nares = plural of naris.
naris (plural nares) = the nostril. External nares open onto the head, internal nares connect the nasal cavity with the mouth cavity (as in Dipnoi). The median naris of Myxini also opens into the mouth. In other fishes the naris on each side is single and leads into a blind sac or the nares are double and connected to one another, via the olfactory chamber.
narrow face = a Newfoundland term for capelin (Mallotus villosus) when the fishing is good. Also called narry face.
narrows = a narrow body of water.
narry face = narrow face.
narsoo = a seven-pronged spear used in India.
naruto = steamed kamaboko (q.v.) prepared as a roll with kneaded and dyed red fish meat rolled into white meat, so that a spiral pattern appears on every cross section (Japan).
narutomaki = naruto.
nasal = pertaining to the nose or olfactory organ.
nasal bone = a paired dermal bone occurring between the premaxilla and the prefrontal, antorbital or lachrymal on either side of the snout and usually enclosing the nares. Lepisosteus has three nasals, prenasal or rostral, adnasal or nasal and premaxillo-nasal or antorbital.
nasal bridge = the tissue between the anterior and posterior nostrils. It may be ridged to direct water into the anterior nostril.
nasal canal = the cephalic lateral line canal before the eyes, starting from the interorbital canal, e.g. in Tripterygidae.
nasal capsule = the structure enclosing the nostrils.
nasal curtain = a fringed flap extending backwards from the nostril of Rajoidei and Myliobatoidei.
nasal fossa = a groove in which the nostril opens.
nasal head spine = a spine on the head of Scorpaenidae members. They are, from anterior to posterior over the top of the head on each side, the nasal, preocular, supraocular, postocular, tympanic, coronal (medial to the tympanic and postocular spines), parietal, and nuchal. Opercular spines are at the postero-dorsal corner of the operculum, preopercular spines line the posterior margin of the preoperculum, and the cleithral and postcleithral spines are just above the opercular spines on the side of the head.
nasal lamella = one of the flaps of tissue in the nostril.
nasal pit = the cavity in which the nasal rosettes are located and which opens by means of one or two nostrils.
nasal process = a vertical process on the anterior maxillary bone in Holostei (Amia and Lepisosteus), not homologous with a similar structure in most teleosts called the ascending process.
nasal rosette = the lamellae and associated elements of the nostril. May be radial, arrow-shaped, parallel or bilateral.
naso-postrostral = nasal bone.
nasohypophysial opening = an opening allowing water into the olfactory organ of Petromyzontidae and Myxinidae. Found on top of the head in Petromyzontidae and in front of the head in Myxinidae.
nasolabial groove = a groove which connects the nostrils and mouth opening in some Elasmobranchii where the nostrils and mouth are close.
nasopalatine canal = the canal which joins the nostril to the intestine in Myxini or is a blind sac ending between the anterior end of the notochord and above the branchial region. Also called nasopalatine duct.
nasopalatine duct = nasopalatine canal.
nasoral groove = a rut between the nostrils and the mouth in some Elasmobranchii.
nasopremaxilla = the premaxilla of Lepisosteus and Amia, formed from a dentigerous premaxilla and the nasals.
natal = of or connected with birth, birthplace, e.g. stream of a fish.
natal stream = stream of birth. Migratory fish often return to this stream which is imprinted on them.
natality = the rate at which new fish are added to population by reproduction.
natant = swimming, or floating on the water surface.
nates = slang for native fish as opposed to hatchery fish, e.g. steelhead, Oncorhynchus mykiss.
natio = race, a local population within a subspecies. Sometimes given a Latin name by Old World biologists, but having no nomenclatural significance, e.g. Salmo trutta natio lacustris.
national cure = a salt cod product where the salted fish are washed and drained only long enough to remove excess water before drying naturally for several days. Salt content after curing is about 20% (minimum 17%)(Portugal).
national food fisheries = those fisheries in fresh and marine waters belonging to and controlled by a state or by profit motivated agencies.
nationality of catch = a catch of fish has the nationality of the flag of the vessel performing the essential part of the operation catching the fish. Exceptions occur when the vessel is chartered by the host country to augment its fishing fleet or the vessel fishes for the country by joint venture contract or similar agreements and the operation of such vessel is an integral part of the economy of the host country.
native = 1) organisms historically indigenous to an area, e.g. native trout for Salvelinus fontinalis as opposed to the introduced brown trout Salmo trutta.
native = 2) a species that is a member of the natural community.
native fishery = harvesting of fish by aboriginal peoples for food or cultural use.
native stock = an indigenous stock of fish that has not been substantially affected by genetic interactions with non-native stocks or by other factors, and is still present in all or part of its original range.
natural bait = live bait (living items used as bait on a hook or in some other fashion, e.g. worms, fish, eggs, etc.).
natural cure = national cure.
natural drying = drying of fish by exposure to sun and wind.
natural feeding = pertaining to or of fishes which feed on natural food.
natural fish = a fish spawned by parents in nature as opposed to a hatchery.
natural flow = the flow of a stream as it would be if unaltered by upstream diversion, storage, import, export, or change in upstream consumptive use caused by development.
natural food = all food organisms naturally present in water on which fishes feed.
natural growth increment = in aquaculture, that part of growth which is due to natural food.
natural host = a fish host where the parasite is found under natural conditions (rather than experimentally). Not the same as typical host, q.v.
natural key = an identification key that reflects evolutionary relationships within the branching sequence of the key.
natural mortality = a measure of the rate of removal of fish from a population from natural causes, not through fishing. Includes predation, cannibalism, senility, disease, pollution, etc. The balance that must be struck between natural mortality and fishing mortality to ensure an effective fishery is difficult. Natural morality can be reported as either annual or instantaneous. Annual mortality is the percentage of this fish dying in one year. Instantaneous mortality is the percentage of fish dying at any one time. Natural mortality is very high for young fish, with more than 99% dying in the first few months of life. Natural mortality for recruited fish is fairly steady at about 0.2, i.e. 2 fish in every 10, for groundfish, lower for Sebastes spp. (ca. 0.1), and higher for small pelagic fish. At a rate of 0.2, the chance of dying of natural causes in 1 in 5 at whatever age the fish happens to be. For a year class however, at a rate of 0.2, 45% of new recruits would die in less than 4 years from recruitment but 1% would survive more than 23 years.
natural range = the geographical range of a species prior to human disturbance.
natural reproduction = reproduction occurring without human influence.
natural return ratio = an estimate of the ratio of naturally produced spawners in one generation to total natural spawners (both naturally and hatchery produced) in the previous generation.
natural stocking rate = a stocking rate calculated only on the biogenic capacity of a body of water.
natural taxon = a species or group of species having a unique history of evolutionary descent. Two or more such species comprise a clade or monophyletic group.
naturalised = said of an alien or introduced species that has become successfully established, reproducing in the wild.
naturally spawning populations = populations of fish that have completed their entire life cycle in the natural environment without human intervention.
nautical mile = now set at 1852 metres, 1.151 miles or 1 minute latitude of the great circle of the earth. Three nautical miles make one league. The British nautical or Admiralty mile was 6080 feet (1853.18 m) while the U.S. nautical mile was 6080.2 feet (1853.24 m). Abbreviated as INM for international nautical mile.
navicular = boat-shaped.
NB = nota bene, take notice, note well. Also n.b.
neallotype = a newly designated type specimen selected in the absence of extant type material, of opposite sex to the neotype.
nap current = a tidal current of decreased range as with a neap tide.
neap high water = the average height of the high waters of the neap tide. Also called high water neaps.
neap low water = the average height of the low waters of the neap tide. Also called low water neaps.
neap tide = a tide of decreased range occurring semi-monthly, between the time of new and full moon. The sun and moon are at right angles to each other so their net gravitational effect on the sea is reduced. The neap tidal range is usually 10 to 30 percent less than the mean tidal range.
near water trawler = a trawler taking voyages of 5-9 days.
Nearctic = the biogeographical realm of North America, excepting southern Mexico.
nearshore fishery = a fishery in Newfoundland carried out between the inshore and offshore waters.
nearshore waters = shallow waters at a small distance from the shore. Also called inshore or onshore waters although the former may be defined as nearer the coast.
neascosis = black-spot disease (the encysted intermediate life history stage of a strigeid trematode found in a fish's skin. The skin develops black pigment over the cysts forming the characteristic spots).
nebbard = nebert.
nebert = the necessary quantity of fish bait (Shetland and Orkneys dialect). Also spelled nebirt, nabert, nebbard, nebir and neburd.
nebir = nebert.
nebirt = nebert.
neburd = nebert.
nec = not (of), nor (of).
necrophagy = eating the dead, carrion-eater.
necropsy = examination and dissection of a dead specimen to determine cause of death or changes due to disease; also used to describe taking of samples for studies such as molecular analyses.
nectobenthic = swimming off the sea bed; also spelled nektobenthic .
neck = 1) fish don't have one, with the arguable exception of seahorses. Some species can move the head and look in different directions despite the lack of a flexible neck, e.g. darters (Percidae).
neck = 2) the narrowing of a placoid scale between its crown and base.
neck = 3) a narrow or constricted part of a structure, as of a bone or a net.
neck = 4) a narrow strip of land connecting a peninsula with the mainland.
neck = 5) a rip, or narrow band of current, flowing seaward through the surf.
neck canal = the one or more ducts in the neck of a placoid scale which radially join the pulp cavity with the exterior and which serve during formation of the scale to contain blood vessel loops.
neck strap = a tissue over the "neck" of some fish embryos which absorbs ovarian milk, q.v., e.g. in Poecilia reticulata.
needle = an implement made to hold a quantity of twine and used to knot meshes in a fish net. (Newfoundland).
needle comb = 20-30 needles arranged in rows on a wooden board attached to a board. Used to catch eels in Japan at night. When an eel is sighted using lights, it is struck on the head and coils around the pole in reaction, and so can be seized by the fisherman.
neflin = dried cod from Newfoundland (Cornish dialect). Also spelled niflin.
negative = in angling, said of fish at the lowest feeding mode, usually because of one or more stress factors in the environment.
negative estuary = estero (a lagoon with greater salinity at its head than its mouth, since evaporation exceeds precipitation there. Found on desert margins of the American southwest and in Mexico).
neglected name = a validly published name that has been overlooked (nomen neglectum).
nehrung = a spit, a long, narrow strip of land paralleling the coast (German but sonmetimes used in English texts). See haff.
nei = not elsewhere included. In fisheries catch statistics, refers to catch data that cannot be linked directly to a State or fishing entity, for whatever reason.
neither fish nor fowl = anything not belonging to a particular class or category; indefinite; having no specific characteristics; neither one thing nor the other.
neither fish nor fowl nor good red herring = anything not belonging to a particular class or category; indefinite; indeterminate; to be hesitant or undecided; having no specific characteristics; neither one thing nor the other. May appear as neither fish nor good red herring, neither fish nor flesh.
nekton = organisms of relatively large size which have fairly strong locomotory powers (as compared to plankton) and swim in the water column independent of currents, e.g. most adult fishes.
nematodiasis = infestation with nematodes.
Nemo = the clown fish in the Pixar computer-animated movie "Finding Nemo", released in 2003. The movie centres around the efforts of the father, Marlin (naturally a clown fish too and not a marlin but this is Walt Disney not ichthyology) to find his lost son.
neo- (prefix) = new.
neo-holaulacorhizy = a modification of the holaulacorhizid type of tooth root in Chondrichthyes where a shallow median groove and extremely expanded pulp cavity are combined (Herman et al., 1994).
neoallotype = neotype is preferred. Information on sex should be garnered separately (allotype being a paratype of opposite sex to the holotype and originally designated by the author, a term not regulated by the International Code of Zoological Nomenclature).
neocotype = a replacement syntype, q.v., designated in the absence of the original type or type series.
neoholotype = a new type specimen selected in the absence of the original type. Neotype is preferred.
neomale = a genetically female fish which has been hormonally masculinised to a phenotypic male.
neomorph = a structure, part or organ developed independently, i.e. not derived from a similar structure, part or organ, in a pre-existing form.
neon tetra disease = a disease caused by the sporozoan Pleistophera hyphessobryconis, and named after the neon tetra fish in which it was first recognised. Whitish patches appear below the skin (destroying the neon stripe in the eponymous fish), muscle tissue is destroyed (causing contortions and abnormal movements), cysts form and release spores, the spores penetrate further into the fish and form more cysts, and are eventually spores are released into the water to infect more fish through food.
neoparatype = a figured specimen used in addition to the neotype. Paraneotype is preferred.
neosyntype = neocotype.
neoteny = achieving sexual maturity while the rest of the body is in the juvenile form (the juvenile form of others of the same group).
neotype = a single specimen designated as the type-specimen of a nominal species-group taxon of which the holotype (or lectotype), and all the paratypes, or all syntypes are lost or destroyed or suppressed by the International Commission on Zoological Nomenclature.
nephric myomere = in eel leptocephali, the number of myomeres or muscle blocks anterior to the end of the kidney is a diagnostic character.
nephridium = small excretory organs with flame cells found in invertebrates and Amphioxi.
nephrocalcinosis = precipitation of calcium phosphate in the kidney tubules, causing renal insufficiency; a common condition in fishes.
nephros = the kidney in fish larvae such as leptocephali.
nerisei-hin = rensei-hin (inclusive term meaning the products made from kneaded fish meat, e.g. kamaboko (q.v.)).
neritic = pertaining to the shallow waters on or above the continental shelf (as opposed to oceanic organisms) from the low tide level to a depth of 200 metres; shelf fauna.
neritopelagic = inhabiting shallow coastal waters over the continental shelf.
nerka virus = a herpesvirus from landlocked sockeye salmon, possibly the same as herpesvirus disease, q.v.
ness = a triangular promontory jutting into the sea, often composed of sand or similar materials.
nessel = a snood of twisted twine fastened to a hook used in fishing for small fish (Cornish dialect).
nessel taker = a mechanism fixed to the beams of a fisherman's cottage for making nessels (Cornish dialect).
nest = 1) a structure created for housing eggs and sometimes young, usually involving some cleaning or grouping of materials such as gravel or weeds, e.g. in Gasterosteidae and many Cichlidae.
nest = 2) a collective noun (a noun that denotes a collection of persons or things regarded as a unit) for fishes.
nester = an ecological group of reproductive guilds (q.v.) where the fish build a nest to protect the eggs or defend the eggs attached to the substrate.
net = an open mesh structure formed by cords linked by knots (or other linking methods such as weaving) used for capturing or confining aquatic organisms like fishes.
net and coble = a beach seine used in Scotland for salmon. The coble is a small, flat-bottomed open boat which may be rowed or under power, used to set the net by paying it out as the boat sweeps round in a circle. The net must be kept in motion while being payed out to surround the fish and bring them into shore. Other restrictions apply in this method of salmon fishing (no stones can be thrown to scare fish into the net and no other nets can be used in conjunction).
net bag = a large, bag-shaped net in which surplus cod are temporarily stored until brought ashore from the inshore fishery (Newfoundland).
net cage = in aquaculture, an open mesh net suspended from a metal frame. Common in Japan.
net day = the daily catch or use of a net, especially when used as a measure of fishing intensity.
net depth = the distance from the headline to the groundrope in a net of specific design. Usually given as the number of meshes.
net drum = a wide spool over which a trawl or purse seine is hauled in, usually hydraulically powered. Also called net roller or transporter.
net fishery = use of gear other than hook and line to catch cod in Newfoundland.
net fishing = 1) use of a net to catch fishes generally.
net fishing = 2) more specifically, the right of taking fish by one net in a particular stretch of water.
net gallows = a frame on which fish nets are hung to dry in Newfoundland. Also called net horse, scaffold and shear.
net gear site = the place in the sea or fresh water where stationary net gear is located.
net ground = an area of foreshore on which fishnets are spread to dry in Newfoundland.
net hauler = a powered winch pulley for helping to haul in gill nets and drift nets.
net hook = a forked wooden structure used to stretch a fish-net when drying it (Newfoundland).
net horse = net gallows.
net increase (or decrease) = new body substance elaborated in a stock of fishes, less the loss from all forms of mortality (Ricker, 1975).
net lifter = net hauler.
net loft = an area in a building for storing and mending fish nets in Newfoundland.
net mender = a man tasked with repairing nets.
net mending = the repair of nets, usually by hand.
net needle = a specialised form of needle used to make or repair mesh nets by hand. Most nets are now made by machinery.
net pen = a fish rearing enclosure used in lakes and marine areas made of net sides and bottom, supported by floats and anchored to the bottom. Keeps out birds, mammals and other fishes.
net pen cage = net pen or net cage.
net preservation = various techniques and processes used to protect a net from the effects of the environment.
net production = production (the total elaboration of new body substance in a stock in a unit if time, irrespective of whether or not it survives to the end of that time. Also called total production).
net reel = a drum on the deck of commercial fishing vessels on which the net and rigging is wound.
net reservoir = a cloth container on a wooden frame used in carp breeding in China.
net roller = net drum.
net room = a specially designed room for storing, mending and preserving nets.
net rope = a float line made of two ropes of opposite twist to prevent kinking. Also called gill rope.
net sonde = net sounder.
net sounder = a transducer mounted on the trawl headline sending signals by cable or acoustically to a recorder on the trawler. It serves to give information on depth, temperature and fish above and below the trawl.
net washer = an industrial machine used on aquaculture facilities to wash fish nets.
net weight = the weight of the fish itself, i.e. the gross weight minus the weight of any bags, trays, wrappings, etc., cf. gross weight.
net winch = a mechanical winch used to haul and store nets, mostly on trawlers.
net-bag = a large, bag-shaped net in which surplus cod are temporarily stored until brought ashore from the inshore fishery (Newfoundland).
net-fishery = use of gear other than hook and line to catch cod in Newfoundland.
net-gallows = a frame on which fish nets are hung to dry in Newfoundland. Also called net-horse.
net-ground = an area of foreshore on which fishnets are spread to dry in Newfoundland.
net-hook = a forked wooden structure used to stretch a fish-net when drying it (Newfoundland).
net-horse = net-gallows.
net-loft = an area in a building for storing and mending fish nets in Newfoundland.
net-mender = a man tasked with repairing nets.
net-winding winch = net winch.
netting = 1) a mesh of various shapes, sizes, materials and construction methods.
netting = 2) nets used for fishing.
netting = 3) the making of a fish net.
netting = 4) the practice or right of fishing with a net.
netting = 5) lint (netting in the main body of a drift or gill net. Also called body, middle twine, middle yarn, sheet, webbing, yarn).
netting twine = the cord used in making fishing nets.
neuracanth = the neural spine.
neural arch = the arch enclosing the spinal cord on the dorsal surface of the vertebrae. Generally continuous in Chondrostei but separate arches in Teleostei give more flexibility. Acipenseridae have two canals, the upper for the longitudinal ligament and the one under it for the spinal cord.
neural canal = the spinal cord canal through the neural arches.
neural crest = part of the neural ridge in embryos that differentiates into various tissues including melanophores, peripheral neurons and head cartilage.
neural groove = a mid-sagittal depression on the surface of the anterior neural plate present during early segmentation.
neural keel = an intermediate stage between the neural plate and the neural rod with a triangular cross-section.
neural plate = thickened epithelium forming the earliest dorsal ectodermal primordium of the central nervous system.
neural process = a dorsal projection of the vertebrae, one on each side of the centrum. These unite to form the neural spine.
neural retina = the retinal epithelium sensitive to light that develops from the inner layer of the optic cup. During hatching it forms several sublayers including the inner ganglion cell layer, interneuronal layers, the outer layer of light sensitive cells and the pigment layer.
neural rod = an intermediate stage in the central nervous system between the neural keel and neural tube with a roughly cylindrical shape but not yet hollow.
neural spine = the dorsal spine on top of the neural arch, directed backwards. These spines are bifid posteriorly in Diodontidae. Also called neuracanth and neurapophysis.
neural tube = the primordium of the central nervous system characterised by a cavity and developing from the neural rod.
neurapophyses = plural of neurapophysis.
neurapophysis (plural neurapophyses) = 1) the structure forming each side of the neural arch.
neurapophysis (plural neurapophyses) = 2) the dorsal process of the neural arch, the neural spine.
neurocoel = the space enclosed by the neural tube.
neurocrania = plural of neurocranium.
neurocranium (plural neurocrania) = the portion of the skull surrounding the brain, including the elements that surround the olfactory, optic, orbital or sphenotic, and otic or auditory capsules and the anterior end of the notochord (endocranium) and the series of overlying dermal bones (dermocranium). Also called braincase.
neuromast = a sensory cell with a hair-like process capable of detecting motion or vibrations in the water. The hair is sheathed in a gelatinous cupula terminalis. May be located in a series as a lateral line, either exposed on the skin or enclosed in a tube-like canal opening to the surface through pores, as individual sense organs exposed on the skin or sunk in a depression (pit organ), or in the semicircular canals of the inner ear.
neuromere = a brain subdivision characterised by a swelling bounded by constrictions.
neuropophysis = dorsal projections of the vertebrae which unite to form the neural arch and spine.
neurotoxin = a nerve toxin.
neurulation = the process of forming a dorsal ectodermal neural tube.
neuston = organisms that float or swim in surface waters.
neutral = in angling, the middle stage of fish activity or when fish can be induced to strike a lure or take a bait.
neutral buoyancy = having the same density as the surrounding water, so it neither sinks nor floats.
neutral buoyancy device = a plastic device used by anglers to determine how much weight is needed to cock a float. Used at home when making up float rigs.
neutral term = a taxonomic term of convenience having no nomenclatural significance or hierarchical rank, e.g. complex, group.
new combination = combinato novum (a new name results from a change in rank or position of an epithet from an earlier name, e.g. transfer to a new genus producing a new combination).
new name = nomen novum.
new replacement name = nomen novum.
new scientific name = a scientific name, available or unavailable, when first proposed for a taxon.
new style = indicates the Gregorian or modern western calendar. Some older fish literature, especially Russian, is dated by the Julian calendar or old style. This may have taxonomic significance in name priority. The Gregorian calendar came into use in Catholic Europe in 1582 (the day after October 4 became October 15), in England in 1752 but only in 1918 in Russia. Abbreviated as NS.
new tank syndrome = the condition in newly set up aquaria where ammonia and then nitrite levels from fish wastes rise to dangerous levels. New aquaria lack sufficient denitrifying bacteria for about a month after set up. See also old tank syndrome.
new water = water free of organic waste, e.g. from springs, wells, fresh rainwater, tapwater as opposed to old water. New water facilitates growth while old water restricts growth because of an overcharge of waste products.
New York-style reel = a fishing reel made in New York of the multiplier type characterised by a counter-balanced crank and sometimes swivelling discs to protect the spool bearings and facilitate oiling.
Newcastle kipper = 1) fat herring, split down the back from head to tail, lightly brined and cold smoked. They may be artificially coloured. Marketed chilled, frozen or canned (sometimes packed in edible oil in Germany).
Newcastle kipper = 2) ground meat made into kipper paste.
Newfoundland banks = areas of shoal water forming the offshore fishing grounds of Newfoundland, Canada. Also called Grand Banks.
Newfoundland fish = cod (Gadus morhua, Gadidae).
Newfoundland fish-box = a jocular term for a sailing vessel engaged in transporting dried cod to foreign markets.
Newfoundland fishery = the marine fishing industry in Newfoundland waters, especially the cod fishery.
Newfoundland trade = the fishery in Newfoundland, especially the supplying of men engaged in the cod fishery and the marketing of the dried and salted product overseas.
Newfoundland-man = an English West Country migratory fishing vessel or a crew member of such a vessel (Newfoundland).
Newfoundlander = a vessel from, or engaged in, the fish trade with Newfoundland.
newlander = an English vessel fishing seasonally in Newfoundland.
nga-bok-chauk = pieces of fish allowed to putrefy before salting and sun-drying (Myanmar).
nga-pi = ngāpi.
ngāpi = a fermented and salted fish paste from Burma (Myanmar). See also garum, balachong and trāsi.
nibble = a delicate or tentative bite on a bait by a fish.
nibble fish = Garra rufa and Cyprinion macrostomum (Cyprinidae) in Turkish hot springs in the Kangal area which clean dead skin fragments from humans with psoriasis. Also called doctor fish and kangal fish.
niboshi = small whole fish, often sardines or similar species (or shellfish) boiled in salt solution or sea-water and subsequently dried in the sun (Japan).
niboshi-hin = an inclusive word for products dried after boiling or steaming (Japan).
nice kettle of fish = pretty kettle of fish (a bad state of affairs; a very difficult and annoying situation; something to be considered or reckoned with. From kiddle, a basket set in the opening of a weir for catching fish).
niche = the habitat and role of an organism (food habits, community relationships, etc.); the range of environmental space occupied by a species.
niche overlap = an overlap in resource requirements by two species.
nick point = the point at which a stream is actively eroding the streambed downward to a new base level.
nictitating eyelid = a membrane which covers the eye, an eyelid, found particularly in sharks.
nictitating membrane = a membrane at the front of the eye which can be pulled over the whole eye, e.g. in some Selachii.
nidamental gland = a specialized portion of the oviduct which secretes nourishing and sometimes protective (shell) coverings about the ovum as it moves posteriorly, e.g. in Elasmobranchii and Holocephali.
nidification = nest building, e.g. preparation of a gravel concavity by Micropterus; evacuation under boulders by Cottus; barrel-like structure of weeds, sand or twigs glued together by Gasterosteus.
niflin = neflin.
nifurprazine = a chemical (1-(5-Nitro-2-Furyl)-2-(6-Amino-3-pyridazl) ethylene hydrochloride) used to combat bacterial infections in fishes, particularly with Aeromonas salmonicida. Also called carofur.
night crawler = a large earthworm used as bait in angling, cf. angleworm. Effective for trout, walleye and bass in North America.
night fishing = fishing at night for those species that are active then, e.g. light-sensitive walleye or scent-sensitive catfishes.
night-line = fishing line with baited hooks left in the water to catch fish over night.
nigiri-zushi = fingers of rice topped with wasabi and raw or cooked fish; the common form of sushi.
nip = a bite in fishing.
nipper = a thick, narrow band of cloth or knitted wool worn around the fingers or palm by a fisherman to protect his hand in line-fishing (Newfoundland).
nipping = biting, usually as a territorial or stress behaviour in fish, occasionally as a feeding mechanism.
nishikigoi = the complete Japanese word for koi (ornamental carp especially bred over centuries for colour patterns and body form). The word means brocaded carp and koi come in various named varieties based on colour, pattern and scales.
nitrate poisoning = although nitrate is less poisonous to fish than ammonia and nitrites (see nitrogen cycle), in high concentrations it is harmful and may also indicate the presence of other toxic waste products (most aquarium test kits measure ammonia, nitrites and nitrates for the nitrogen cycle, not a wide range of toxic wastes). A level of 50 mg/l is the maximum for fish tolerant of nitrates, ideally the aquarium should have levels below 25 mg/l, and for nitrate-intolerant species much lower. Nitrate poisoning is usually a chronic effect, causing poor health and growth, a reluctance to breed, susceptibility to disease from other causes and is probably the cause of black chin disease, q.v. Excessive algae growth is a sign of too much nitrate. Changing the water is a simple solution and nitrates can be removed from tap water by reverse osmosis or the appropriate ion-exchange resin.
nitrofuran = one of a series of related chemicals used against gram negative bacteria in fishes.
nitrogen cycle = in an aquarium, fish wastes, decaying food and plant material produce ammonia and nitrites which are harmful to the fish. Nitrobacter bacteria convert these wastes into a relatively harmless nitrate in a mature aquarium (see above). The danger to fish lies in a new aquarium where the bacteria and filtration systems have not been established long enough to be effective in the conversion. Build up of sufficient numbers of bacteria can take several weeks and a new aquarium can have a toxic ammonia surge. Test kits allow the aquarist to measure the chemical health of the aquarium.
nitrogen narcosis = recovery of fish suddenly from deep water can case expansion of gases by rapid decompression, harming the fish. Applies to humans too.
nitrogen supersaturation = water in which the concentration of dissolved nitrogen exceeds the saturation level of water. Excess nitrogen can harm the circulatory system of fish.
Nitrosomonas = the genus of nitrifying bacteria found in biological filtration systems in aquaria.
NL = abbreviation for notochord length.
no. = abbreviation for numero, meaning number.
no commercial value = a phrase used on packages of preserved scientific specimens sent through the mail to other institutions for purposes of a customs declaration.
no take reserve = no take zone.
no take zone = a marine protected area where catches or removal of organisms are prohibited. Abbreviated as NTZ.
no-effect level = conditions or concentrations of a chemical which have no adverse effect on fish life (usually in the statistically significant sense).
nob. = abbreviation for nobis.
nobbin = a fleshy portion of dried salt fish, small enough to be sold by measure. See cod nobbin (Yorkshire dialect).
nobbing = removing the head and guts from such fatty fish as herring by partially severing the head, then pulling it away with guts attached but the gonads left in.
nobis = to or of us; used after a scientific name to indicate the author's responsibility for its description, or for an action or proposal.
nocardiosis = a chronic systemic bacterial disease caused by Nocardia asteroides. Lesions are formed internally and externally and additionally fish show popeye and anorexia. Some fish, such as salmonids, may show no external symptoms although the disease is fatal from internal lesions. Nocardiosis is a zoonose, a disease capable of infecting humans, entering through skin abrasions and causing skin granulomas.
nocioceptor = a peripheral nervous receptor, sensitive to noxious stimuli and reporting to the central nervous system where pain is perceived and motor responses initiated. Fish can sense pain but these receptors provide no evidence of a psychological experience of pain.
nocturnal = active at night; pertaining to the night; lasting only one night.
nocturnal mooring = a night-time behaviour in Monocanthidae where they orally attach to sponges, tunicates, rope and fishing line in nature as a means of resting from currents.
nodulose = having small nodules, swellings or knobs.
nom. = abbreviation for nomen, meaning name.
nom. abort. = abbreviation for nomen abortivum.
nom. ambig. = abbreviation for nomen ambiguum.
nom. conf. = abbreviation for nomen confusum.
nom. confus. = abbreviation for nomen confusum.
nom. cons. = abbreviation for nomen conservandum.
nom. conserv. = abbreviation for nomen conservandum.
nom. dub. = abbreviation for nomen dubium.
nom. hybr. = abbreviation for nomen hybridum.
nom. illeg. = abbreviation for nomen illegitimum.
nom. illegit. = abbreviation for nomen illegitimum.
nom. inq. = abbreviation for nomen inquirendum.
nom. inval. = abbreviation for nomen invalidum.
nom. legit. = abbreviation for nomen legitimatum.
nom. monstr. = abbreviation for nomen monstrositatum.
nom. non planta = abbreviation for nomen sed non planta.
nom. non rite public. = abbreviation for nomen non rite publicatum.
nom. nov. = abbreviation for nomen novum.
nom. nud. = abbreviation for nomen nudum.
nom. oblit. = abbreviation for nomen oblitum.
nom. provis. = abbreviation for nomen provisorium.
nom. rejic. = abbreviation for nomen rejiciendum.
nom. rev. = abbreviation for nomen revivisco.
nom. superfl. = abbreviation for nomen superfluum.
nomad = fish without a home range that move widely.
nomen (plural nomina) = name.
nomen abortivum = a name contrary to the International Code of Zoological Nomenclature as the Code existed at the time of publication. Abbreviated as nom. abort.
nomen alternativum = alternative name (two names for the same taxon, of the same rank, published simultaneously by an author). Abbreviated as nom. alt.
nomen ambiguum = an ambiguous name, one used by different authors for different taxa over so long a period that is has become a persistent cause of error and confusion. Abbreviated as nom. ambig.
nomen collectivum = collective group (an assemblage of nominal species that cannot be placed with certainty in known genera; names proposed expressly for collective groups are treated as generic names).
nomen confusum = confused name a name based on elements of more than one species from which it is impossible to select a lectotype. Abbreviated as nom. conf. or nom. confus.
nomen conservandum = a name preserved by the International Commission on Zoological Nomenclature and entered on their Official Lists even though it strictly contravenes one or more provisions of the Code. Abbreviated as nom. cons. or nom. conserv.
nomen correctum = a corrected name or 'improved' name, an available name which is a mandatory and allowable emendation of an imperfect name or of a taxonomic name higher than family (which is not subject to name form and ending regulations). Does not depend on transfer in taxon rank or assignment (an emended name).
nomen dubium = a doubtful or dubious name not certainly applicable to any known taxon; a name which cannot be recognized because of inadequate description, figure, etc. May possess availability conducive to uncertainty and instability. Abbreviated as nom. dub.
nomen hybridem = hybrid name, formed by combining words from different languages. Abbreviated as nom. hybr.
nomen illegitimum = illegitimate name, a validly published name that must be rejected for the purposes of priority in accordance with the International Code of Zoological Nomenclature. Abbreviated as nom. illeg. or nom. illegit.
nomen imperfectum = an imperfect name, an available name which when originally published met all mandatory requirements of the International Code of Zoological Nomenclature, i.e. met all criteria of availability but which contained some defect needing correction, such as names incorporating hyphens, diacritical marks or apostrophes, higher taxon names using an incorrectly formed stem.
nomen inquirendum = a name which should be investigated. Abbreviated as nom. inq.
nomen invalidum = invalid name, a name that is not validly published or is unavailable. Abbreviated nom. inval.
nomen inviolatum = an inviolate name, all available names not subject to any sort of alteration from their originally published form, i.e. they were correct as originally published and need no correction or emendation.
nomen legitimatum = legitimate name, a valid name published in accordance with the provisions of the International Code of Zoological Nomenclature. Abbreviated as nom. legit.
nomen monstrositatum = a scientific name based on a monstrosity (a physically abnormal specimen). Abbreviated as nom. monstr.
nomen negatum = a denied name, an unavailable name which has incorrect original spellings as defined by the International Code of Zoological Nomenclature.
nomen neglectum = a neglected name, a validly published name that has been ignored or overlooked.
nomen non rite publicatum = not properly published name, used to indicate that a name has not been validly published according to the provisions of the International Code of Zoological Nomenclature. Abbreviated as nom. non rite public.
nomen novum = a new name which is published to replace an earlier name (and valid only if the latter is preoccupied) and which is expressly proposed as a replacement name; a new name, not to be confused with a new species, or a new genus, etc., which represent new taxa. Commonly applied to names proposed to replace junior homonyms. Abbreviated as n. n., n. nov. or nom. nov.
nomen nudum = a naked name, a name that, if published before 1931, was not accompanied by a description, definition, or indication, or if published after 1930, is not accompanied by a statement that purports to give characters differentiating the taxon; or is not accompanied by a definite bibliographic reference to such a statement; or is not proposed expressly as a replacement for a pre-existing available name. A nomen nudum is not an available name, and therefore the same name may be made available later for the same or a different concept; in such a case it would take authorship and date from that act of establishment, not from any earlier publication as a nomen nudum. Abbreviated as n. n., n. nov. or nom. nud.
nomen nullum = a null name, an unavailable name which as defined by the Code is a non-demonstrably intentional change of an original spelling, i.e. a form of incorrect subsequent spelling.
nomen oblitum = a forgotten name, an unused senior synonym rejected under the provisions of the International Code of Zoological Nomenclature. Formerly a senior synonym not once applied to a particular taxon as its presumably valid name for the immediately preceding 50 years (other than in a synonymy, listing in an abstracting publication or a nomenclator) and to which taxon has been currently been applied a junior synonym by at least 5 different authors in at least 10 publications during the immediately preceding 50 years. Such a name, unless otherwise ruled, is to be rejected for the purposes of the Law of Priority but not for those of the Law of Homonymy. No longer recognised. After 1 January 2000 applied to a name, unused since 1899, which as a result of an action taken under the Code does not take precedence over a younger synonym or homonym in prevailing usage; the younger name which takes precedence over the nomen oblitum may be called a nomen protectum. A nomen oblitum remains an available name. Abbreviated as nom. oblit.
nomen perfectum = a perfect name, an available name which when originally published met all mandatory requirements of the Code and needed no correction of any kind, but which is validly alterable by change of ending.
nomen praeoccupatum = a preoccupied name or junior homonym, a name already in use for another taxon based on a different type.
nomen protectum = a protected name applied to a name which has been given precedence over its unused senior synonym or a senior homonym relegated to the status of nomen oblitum.
nomen provisorium = provisional name, a name proposed provisionally in anticipation of the acceptance of the taxon concerned at a future date. Abbreviated as nom. provis.
nomen rejiciendum = 1) rejected name, any name (other than the valid name of a taxon) which has been officially rejected under the provisions of the International Code of Zoological Nomenclature. Abbreviated as nom. rejic.
nomen rejiciendum = 2) a family or genus name that should replace another well-known name but which is rejected in favour of a nomen conservandum, q.v. Abbreviated as nom. rejic.
nomen revivisco = name revived, used of a name revived or reinstated, e.g. from an earlier synonymy.
nomen sed non planta = used to indicate that a author has applied the name to a taxon other than that to which the type of the basionym, q.v., belongs.
nomen substitutum = substitute name, any available name whether new or not, proposed as replacement for any invalid name, such as a junior homonym. A substitute name proposed specifically for a preoccupied name is a nomen novum.
nomen superfluum = superfluous name, a name incorrectly applied to a taxon. When first applied the taxon included the type of another name which should have been used under the provisions of the International Code of Zoological Nomenclature. Abbreviated as nom. superfl.
nomen translatum = a transferred name, an available name which has been altered (usually in ending only), the change depending on transfer from one taxonomic rank to another, or from one taxon to another. Authorship and date remains as for the original name.
nomen triviale = trivial name, the specific name or specific epithet. Applied by some authors in the same sense as vernacular name.
nomen vanum = a vain name, an available name consisting of unjustified but intentional emendation of a previously published name. It has status in nomenclature with its own authorship and date.
nomen vetitum = an impermissible name, an unavailable name published for divisions of the genus group other than genus and subgenus, which are not accepted by the International Code of Zoological Nomenclature.
nomenclator = a list of scientific names used for nomenclatural purposes rather than taxonomic ones.
nomenclatorial = pertaining to a nomenclator.
nomenclatural = pertaining to nomenclature; nomenclatural act.
nomenclatural act = a published act which affects the nomenclatural status of a scientific name or the typification of a nominal taxon; available nomenclatural act is one that is published in an available work; invalid nomenclatural act is any nomenclatural act which is not valid under the provisions of the International Code of Zoological Nomenclature; unavailable nomenclatural act is one published in an unavailable work; valid nomenclatural act is one that is accepted under the provisions of the Code, i.e. the earliest available act not contravening any provision of the Code.
nomenclatural status = the status of a scientific name, nomenclatural act or work according to the provisions of the International Code of Zoological Nomenclature.
nomenclatural synonym = homotypic synonym (a synonym based on the same nomenclatural type).
nomenclatural type = the single element of a taxon to which its name is permanently attached; type; nomenifer; onomatophore.
nomenclature = the system of scientific names applied to taxa, or the application of these names.
nomenifer = the name bearer; nomenclatural type; type; onomatophore.
nomenspecies = a species defined on the characters of the type specimen; typological species.
nomina = plural of nomen.
nominal = in fisheries studies, refers to quantities as they are reported without any analysis or transformation, e.g. nominal catch, nominal effort.
nominal catch = the sum of the catches that are landed, not including unreported discards, before any analysis. The nominal catch may differ from actual landings because of errors in reporting, the use of some fish in fish meal and other complications.
nominal effort = fishing effort or vessel carrying capacity that has not been standardised. When catchability changes through, for example, changes in gear technology, trends in nominal effort can be misleading as a picture of trends in exploitation.
nominal form = in name only; a named taxon of questionable status. The word nominal is often used to imply that although the species have been named, they may not be valid taxa, e.g. the genus x has 20 nominal species implies one or more may be synonyms.
nominal taxon = the taxon defined by its type, type-genus in the case of family, type-species in the case of genus, and type-specimen in the case of species.
nominate = nominotypical; used in older editions of the International Code of Zoological Nomenclature.
nominate form = name-bearing taxon, e.g. the nominate subspecies has the same specific and subspecific epithets and is the oldest valid name for the species.
nominotypical = of a subordinate taxon, that it contains the type of a subdivided higher taxon, and bears the same name, with a suffix in family-group names which is amended according to rank.
non = not (of), indicates in a synonymy that the name that follows is a homonym of an earlier author.
non aliorum = not of other authors. Abbreviate as non al.
non.....nec = neither (of).....nor (of), used in citing a homonym.
non viso = not seen. Abbreviated as n. v.
non-allocated species = those fish species for which a total allowable catch has not been specified. Does not include species whose fishing is prohibited.
non-commercial fisherman = a fisherman who is not licensed and fishes for himself. Includes anglers.
non-consumptive use = use of aquatic resources without consumption, e.g. scuba diving, observing fishes migrations in streams, or even valuing natural resources without observing them.
non-consumptive water use = use of water that does not deplete water supplies, e.g. fishing.
non-contracting party = a country that has not signed and is not obligated to aid by the terms of an international fishing agreement.
non-enzymatic browning reaction = browning (discolouration of fish, especially of dried or canned products, caused by a deteriorative reaction between amino groups of proteins and carbonyl groups of sugars during storage. There are also flavour changes and loss of some nutritive value. Known also as the Maillard reaction).
non-established = introduced species not reproducing.
non-game fish = any wild fish not classified as a game fish by the state.
non-harvestable = pertaining to a fish stock or a part of a stock not available for commercial use.
non-monetary benefits = benefits from a fishery that cannot be measured in economic terms, e.g. enjoyment of a lifestyle.
non-native = said of a species deliberately or accidentally introduced by a human agency to an area outside its natural range and which is reproducing.
non-occlusible = the teeth of the upper and lower jaws not fitting together and so preventing mouth closure.
non-point source pollution = polluted runoff from agriculture, mining, timber harvesting and other sources that are not confined sources.
non-predatory fish = a species of fish not normally feeding on other fishes.
non-pressure stock = any stock large enough to allow unrestricted fishing.
non-reporting = the proportion of captures not reported to the appropriate authorities, e.g. tagged fish recovered but tags not turned in.
non-retention = for conservation purposes, fish caught by anglers must be returned alive to the water. Also called catch and release, closed to retention and daily limit 0.
non-selective feeding = a way of feeding in which no choice as to the kind of food occurs.
non-spawner = any mature fish which does not spawn.
non-squamous = lacking scales.
non-target species = species for which the gear is not specifically set, although they may have immediate commercial value and be a desirable component of the catch.
non-trophic = fasting, or periods when a fish does not eat, e.g. non-parasitic lampreys that do not feed as adults.
nondescript = not yet described; used in older literature for an undescribed species.
nonextant = no longer existing; applied to specimens in a collection.
nonparasitic lamprey = a lamprey (Petromyzontiformes) which does not feed as an adult but relies on food reserves stored as an ammocoete, reproduces and dies.
nonsquamous = non-squamous.
nonwithdrawal use = use of water resources that does not require their diversion, e.g. conservation of fish.
noodle rod = a long, soft, light action fishing rod used for light lines.
noodling = capturing fish by hand, often in murky waters under logs and boulders or in mud holes; may be restricted to use of a hook or snare type device, with or without a short attached line, manipulated by hand when a person is in or under the water. See also grabbling, hand-fishing and hogging.
Nor-Loch trout = not a fish but a cant phrase for a joint or leg of mutton, bought for a club of people who used to meet near the North Loch in Scotland.
Nordmore grate = a groundfish excluding device used on small-meshed shrimp trawls introduced in Canada in 1993.
normal tide = a non-technical term synonymous with tide; use discouraged.
norsel = a short piece of line on a drift net used to attach the hanging line to the head or float line at regular intervals. Also called ossel.
northern cod = cod stocks of the waters adjacent to the north-east coast and Labrador, especially those of the Hamilton Banks.
northern pikes = 1) more than one Esox lucius.
Northern Pikes = 2) a Canadian rock group from Saskatchewan.
norward = a particular type of net (Sussex dialect).
Norwegian cured herring = hard cured, fat summer herring that have empty guts having been kept alive in the sea.
Norwegian milker = milker herring (Dutch cured herring with the gonads left in the fish. Usually packed in small barrels with about 12 fish for the North American delicatessen trade. Also called melker).
Norwegian silver herring = light cured herring that keeps well at room temperature.
Norwegian sloe = hard-cured large herring.
nose = the northeast projection of the Grand Bank of Newfoundland lying outside the Canadian 200-mile fishing zone. See also tail.
nose velocity = water velocity as measured in front of a fish.
notal = dorsal, pertaining to the back.
notch = 1) an indentation, usually in a fin, dividing it into two parts or lobes.
notch = 2) wedge (a small, cut-out and lens-less portion of the pupil margin of the eye. This widens the field of vision and allows more light to enter the eye, rather than falling on the iris. Usually found antero-ventrally for improving forward vision. Found in various species of salmonids and cyprinids, for example. Also called pimple. See also aphakic space).
notche = notch (2).
note = a scientific publication shorter than a paper.
notice action = an action that a fishery manager can take without passing an amendment to existing regulations because the action was pre-specified, e.g. closing a fishery if catches exceed a set limit.
notochord = the skeletal rod consisting of a sheath firmly packed with cells which lie above the gut and below the nerve cord. The notochord is persistent when it remains as a continuous skeletal support (e.g. Amphioxi, Holocephali, Acipenseridae, Petromyzontiformes, etc.) and is constricted when displaced by vertebral centra, occupying anterior and posterior cavities.
notochord length = the distance from the snout tip to the posterior tip of the notochord. Abbreviated as NL.
notopterygia = plural of notopterygium.
notopterygium (plural notopterygia) = dorsal fin(s) (the unpaired fin(s) on the midline of the back. In Pleuronectiformes it is on the opposite side to the anus. In Centriscidae the hind end of the fish has been rotated under the fish so the dorsal fin is on the under surface. Abbreviated as D, D1, D2, or D3 respectively for the only, first, second or third dorsal fins (or their rays and spines). It functions to prevent rolling).
nov. = novum, meaning new.
nov. n. = nomen novum.
nov. sp. = nova species, meaning new species (species nova is to be preferred).
novie = a Nova Scotia fishing craft (Newfoundland).
novus = new. Note the ending changes with the gender of the noun, hence nomen novum and species nova. Abbreviated as nov.
nr = number.
NTZ = no take zone (a marine protected area where catches or removal of organisms are prohibited).
nubbin = bass (Micropterus spp., Centrarchidae) too short to meet tournament standards; usually less than 14 inches (ca. 36 cm). Also called baby, dink, throw back, pop corn, and slick.
nubble = a small lump or protuberance, e.g. on the head of sculpins.
nuchal = 1) pertaining to the nape.
nuchal (plural nuchalia) = 2) extrascapula (one of a series of small bones bordering the posterior margin of the skull roof in primitive Teleostomi. They apparently originate from enlarged scales. One of 2-8 bones known variously as cervicals, postparietals, scale bones, supratemporals or tabulars). Also called nuchalium.
nuchal disc = found in Siluridae.
nuchal gap = the gap between the cranial and thoracic armour in Placodermi.
nuchal head spine = a spine on the head of Scorpaenidae members. They are, from anterior to posterior over the top of the head on each side, the nasal, preocular, supraocular, postocular, tympanic, coronal (medial to the tympanic and postocular spines), parietal, and nuchal. Opercular spines are at the postero-dorsal corner of the operculum, preopercular spines line the posterior margin of the preoperculum, and the cleithral and postcleithral spines are just above the opercular spines on the side of the head.
nuchal hump = a hump of tissue behind the head seen in some spawning or fast-current fish, e.g. Cyprinidae, Salmonidae, Cichlidae.
nuchal thorn = a strong spine on the nape in Rajidae.
nuchalia = plural of nuchal.
nuckie = nucky.
nucky = a fish hook (Shetland and Orkneys dialect).
nuclear family = where both parents equally share the duties of caring for the young; usually formed by monogamous, open-water brooders, although exceptions are common, e.g. in the Cichlidae. Sexes are difficult to separate on external experience. Also called parental family.
nuclear predator = the main predator on a fish. See also follower.
nucleus = 1) the centre part of a scale, the first part to appear in growth; the focus.
nucleus = 2) the core or primordium of an otolith; no longer used. Also called kernel.
nud = the pull of a fish on a fishing line (Shetland Isles dialect).
nugget = bite (a small piece of fish breaded or coated with batter, weighing less than 1 oz. Of various shapes such as round, square, or irregular. May be cut from regular blocks or blocks of minced fish. Generally sold by count, 25-35 per lb. Also called cubes, petites, and tidbits).
nuisance species = any introduced species that affects the native species adversely.
null name = nomen nullum.
number-at-age = the number of fish in each age class of a stock, in a particular year.
numericlature = an attempt to express the classification of animals in numbers, so that each taxon name is represented by a numerical code, the structure of which indicates its taxonomic position, rank and affinities.
nun buoy = a buoy tapered at each end; a red nun buoy indicates the starboard side of the channel when moving upstream from the sea.
nuoc-mam = a clear, amber, fermented fish sauce of Vietnam, made by stacking small fishes in alternate layers of salt flavouring ingredients with spices added. Decanting the digesting enzymes takes several months.
nuptial = associated with breeding - nuptial coloration, nuptial tubercles, etc.
nuptial dress = the breeding colours, tubercles and other attributes found on fish in the breeding season.
nuptial efflorescence = nuptial tubercle.
nuptial stripe = a coloured stripe, often seen in cichlids, which becomes prominent during courtship.
nuptial tubercle = breeding tubercle (usually small, raised, epidermal structures on regions of the head, body, or fin rays where two individuals come in contact. May consist of aggregations of non-keratinized epidermal cells, the same with a light, superficial keratinized cuticle, or with substantial number of fully keratinized cells that are organized to form a discrete, usually conical cap. Breeding tubercles may function to maintain body contact between the sexes during spawning; in the defence of nests and territories; in the stimulation of females in courtship; and in some forms perhaps in sex and species recognition. Found in 15 families of 4 orders; Salmoniformes, Gonorhynchiformes, Cypriniformes, and Perciformes (Wiley and Collette, 1970)).
nursery = 1) an area favoured for birth or egg deposition where young can grow.
nursery = 2) a pond system intermediate between the hatchery and grow-out stages in aquaculture.
nursery phase = culture of postlarvae from metamorphosis to stocking in on-growing ponds or release in the wild.
nursery pond = nursery (2).
nutrient theft = the effect of a parasitic infection in fishes reducing, for example, egg and clutch size.
nutritional gill disease = hyperplasia of gills caused by a deficiency of pantothenic acid in the diet.
nutritional requirement = organic compounds and minerals necessary in the diet for the optimal development, growth and reproduction of a fish.
nycthemeral = a physiological time unit, 24 hours made up of one day and one night.
nyctipelagic = pertaining to organisms that migrate into surface waters at night.
nyctoepipelagic = migrating from deep waters to the epipelagic zone at night.
nymph = an artificial fly made to sink below the surface and imitate immature insects (true nymphs).
nymphing = 1) the feeding of trout on nymphs near or on the stream bed.
nymphimg = 2) fishing with an artificial fly resembling a nymph and weighted to sink.
nystagmus = fixation of the eye on an object while the body is rotating and the return of the eye to its normal position when the eye has rotated to its anatomical limit.
© Brian W. Coad (www.briancoad.com)