Glossary of Fishery Terms - F

F

• Farmed fisheries - are fisheries where the fish are farmed using aquaculture techniques. They can be contrasted with wild fisheries.

• Fecundity - the number of eggs a fish produces each reproductive cycle; the potential reproductive capacity of an organism or population. Fecundity changes with the age and size of the fish.

• Fish - a true fish is a vertebrate with gills that lives in water. However, in the context of fisheries, the term "fish" is generally used more broadly to include any harvestable animal living in water, including molluscs, crustaceans and echinoderms.

• the term "shellfish" refers to molluscs
• the term "finfish" refers to bony fishes, sharks and some rays
• the term "scalefish" refers to fish bearing scales
• the term "fish" can refer to more than one fish, particularly when the fish are from the same species
• the term "fishes" refers to more than one species of fish

• Fishery - the activities leading to and resulting in the harvesting of fish. It may involve capture of wild fish or raising of fish through aquaculture. A fishery is characterised by the species caught, the fishing gear used, and the area of operation.

• Fishmeal - protein-rich animal feed product based on fish.

• Fishing vessel - any vessel normally used for the harvesting of living aquatic resources or in support of such activity. This includes vessels which provide assistance to other fishing vessels such as supply, storage, refrigeration, transportation or processing (mother ships).

• Fishing fleet - an aggregation of fishing vessels of a particular country, such as the Russian fishing fleet, or using a particular gear, such as purse seine fleet.

• Flushing time - the time required to replace all the water in an estuary or harbour by the actions of currents and tides.

• Fork length - in fishes with forked tails, this measures from the tip of the snout to the fork of the tail. It is used in fishes when is difficult to tell where the vertebral column ends.

• Forage fish - are small fish which are preyed on by larger predators. Typical ocean forage fish are small, filter feeding fish such as herring, anchovies and menhaden. They compensate for their small size by forming schools. See bait fish.

• Foreshore - intertidal area between the highest and lowest tide levels

• Founder effect - the loss of genetic variation when a new colony is established by some individuals moving to a new area that is unoccupied. As a result the new population may be distinctively different from its parent population.

• Free-diving - diving under water without the assistance of breathing apparatus to collect oysters, abalone, corals, sponges, crayfish etc. The gear usually includes a snorkel, face mask, flippers, weight belt and wet suit.

• Front - region of sharp gradient in temperature or salinity, indicating a transition between two current systems or water masses. Fronts are usually associated with high biological activity and high abundance of highly migratory resources such as tuna. They are actively sought as fishing areas and can be monitored by satellite remote sensing.