Glossary

The words of the angler and the ichthyologist

This glossary defines the technical terms used in the species sheets. Anatomy words describe the fish's body; ecology words, its life and habitat; fishing words, the ways of catching it.

Anal (fin): Unpaired fin located under the body, behind the anus. Its shape and the number of its rays help identify the species.

Anadromous: Describes a fish that lives in the sea and migrates up into fresh water to breed. The opposite is catadromous.

School: A large group of fish of the same species swimming together, to protect themselves from predators and hunt more efficiently.

Benthic: Living on the bottom or very close to it, as opposed to pelagic. Related term: demersal.

Bycatch: Fish caught unintentionally while targeting another species. Also called incidental catch. Often discarded, sometimes protected.

Catadromous: Describes a fish that lives in fresh or brackish water and migrates down to the sea to breed. The opposite is anadromous.

Cephalopod: A marine mollusc such as the cuttlefish, squid or octopus. Frequent prey of many predators in this book.

Demersal: Living near the bottom, without necessarily resting on it. Groupers, dentex and seabreams are demersal fishes of the continental shelf.

Dorsal (fin): Fin located on the back. It may be single or divided into a spiny part and a soft part.

Estuarine: Relating to the estuary, the area where a river meets the sea and the water is brackish.

Euryhaline: Able to tolerate wide variations in salinity. Euryhaline species move between lagoon, brackish water and sea.

Spawning ground: A place where fish breed and lay their eggs.

Fusiform: Spindle-shaped: an elongated body, tapered at both ends, the hydrodynamic profile of fast swimmers such as tunas.

Gregarious: Living in groups. Gregarious species form schools.

Jig: A heavy metal lure worked vertically, letting it sink and then lifting it in jerks. Fishing with a jig is called jigging.

Juvenile: A young fish that has not yet reached sexual maturity. Releasing it protects the renewal of the species.

Lagoonal: Relating to the lagoon, a shallow, calm stretch of water separated from the sea by a strip of land.

Lure: An artificial bait imitating prey: crankbait, soft plastic, spoon, popper, stickbait.

Lateral line: A line of sensory receptors running along the flank, which detects vibrations and water movements.

Livery: The set of colours and patterns of a fish. It can vary with age, habitat or season.

Maturity: The stage from which a fish can breed. The size at first maturity is a key benchmark for stock management.

Nursery: An area, often in a lagoon or along the coast, where juveniles grow up sheltered from predators before moving offshore.

Operculum: The bony flap that covers and protects the gills, on the side of the head.

Oviparous: Egg-laying. Most bony fishes are oviparous.

Ovoviviparous: Whose eggs hatch inside the female, which gives birth to fully formed young. Common in some sharks.

Longline: A line carrying many baited hooks, set at sea and then hauled. A major commercial gear for pelagics.

Pectoral (fin): A paired fin located on each side of the body, just behind the gills. Used to steer and stabilise the fish.

Caudal peduncle: The narrow part of the body linking the trunk to the tail fin. Often fitted with keels in fast swimmers.

Pelagic: Living in open water, far from the bottom. Large pelagics, such as tunas and marlins, roam the open sea.

Pelvic (fin): A paired fin located under the body, towards the front. Also called the ventral fin.

Finlets: Small separate fins located behind the dorsal and anal fins, characteristic of tunas and Spanish mackerels.

Continental shelf: The shallow submerged extension of the continent, before the slope down to the deep sea. Rich in demersal fishes.

Batch spawner: A fish that does not lay all its eggs at once but in several releases spread over time.

Spiny rays: Rigid, sharp rays supporting the front part of some fins, as opposed to soft, flexible rays.

Biological rest (closed season): Period during which fishing is closed to let fish reproduce. In Côte d’Ivoire, it is set each year by the ministry, usually from 1 July; dates, zones and gear change from one year to the next: that year’s notice is authoritative.

Backwash: The return movement of waves on the beach, in the surf zone. Several species hunt there in the breaking waves.

Brackish: Describes water with a salinity between fresh water and seawater, typical of estuaries and lagoon inlets.

Seine: A large net encircling a school of fish. The purse seine is the tuna boats' gear; the beach seine is hauled from the shore.

IUCN status: The level of threat assigned to a species by the International Union for Conservation of Nature. See the scale below.

Trolling: A technique of towing one or more lures behind a moving boat. The leading method of big-game fishing.

Upwelling: The rise of deep, cold, nutrient-rich water towards the surface. On the Ivorian coast, it triggers the main fishing seasons.

Viviparous: Giving birth to fully formed young, nourished inside the mother. The case of many sharks, including the hammerhead.

Zooplankton: All the tiny animals drifting in the water. The basis of the diet of sardinellas, bonga shad and other small pelagics.

The IUCN conservation status scale

The International Union for Conservation of Nature ranks species according to their risk of extinction, from least to most threatened: Least Concern (LC), Near Threatened (NT), Vulnerable (VU), Endangered (EN), Critically Endangered (CR). In addition there are the categories Data Deficient (DD), when information is lacking, and Not Evaluated (NE). In this book, the status appears on each species' ID card. A species classified VU, EN or CR calls for particular vigilance, or even a complete halt to catching it.