Glossary |
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| TAC - see: |
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| target catch | |
| That portion of the catch which is retained on board and which was the focus of a directed fishery (i.e., it was being targeted). | |
| territorial sea | |
| The territorial sea is that area of water adjacent to the coast over which the littoral State is permitted by international law to exercise sovereign competence for purposes of jurisdiction, control and exploitation, subject only to a general right of innocent passage by foreign ships. The legal limit on the breadth of the territorial sea has varied at different periods (and prior to the negotiation of the LOS Convention there were widely varying claims) although the LOS Convention now provides that every State has the right to establish a territorial sea of not more than 12 miles, measured from its baselines. | |
| total allowable catch (TAC) | |
| The total regulated catch from a stock in a given time period, usually a year. The LOS Convention requires coastal States to determine the (total) allowable catch of the living resources in its EEZ. | |
| trammel nets IMAGE | |
| Trammel nets are similar to gillnets, except that instead of being used singly, three walls of netting are used. The two outer walls are of a larger mesh size than the loosely hung inner netting panel, in which the fish are caught. | |
| transboundary stock | |
| The term transboundary stock is often used in a general sense to mean any fish stock which crosses a jurisdictional boundary, that is either between two coastal States' EEZs or territorial seas or between a coastal State's EEZ and the high seas). However, it is often used only in the former sense, to distinguish such stocks from straddling stocks. | |
| traps | |
| Traps are devices which are designed to catch fish, crustaceans or molluscs, by luring the catch into it either by bait or because the trap appears to provide some sort of refuge. Most traps are set on the seabed with a haul-in line, surface float and buoy to mark their position. There are many types of trap, depending on the target species, although fish trap terminology is not clearly defined and a "trap" may mean anything from a box-like structure dropped to the seabed to an open-topped complex of netting set at the surface. Examples include pots, fyke nets and stow nets. | |
| trawls | |
| Trawls are towed nets consisting of a cone shaped body, closed by a bag or codend and extended at the opening by wings. Strong steel cables (referred to as warps) connect the net to the trawler. They can be towed by one or two boats and, according to the type, are used on the bottom (bottom trawls) or in midwater (midwater or pelagic trawls). In certain cases, as in trawling for shrimp or flatfish, the trawler can be specially rigged with outriggers to tow two (or even four) trawls at the same time (double rigging). | |
| trolling IMAGE | |
| Trolling is a method of fishing using simple long lines, with natural or artificial bait, and dragged behind the boat near the surface or at a certain depth. Several lines (up to 20) are usually towed at the same time, with the help of outriggers. Weights can be attached to the lines if the target fish is found at a greater depth. | |
| trophic level | |
| Theoretical term in ecology which describes one of a succession of steps in the transfer of matter and energy from the lowest species to the highest species in a community, such as a marine ecosystem. In other words, it describes the process of energy transfer from species such as phyto-plankton and zooplankton through smaller fish to larger fish and marine mammals and, in some cases, humans. | |
| turtle excluder device (TED) | |
| TEDs are panels of large mesh webbing or metal grids inserted into the funnel shaped shrimp nets. As the nets are dragged along the bottom, shrimp and other small animals pass through the TED and into the cod end of the net, the narrow bag at the end of the funnel where the catch is collected. Sea turtles, sharks, and fish too large to get through the panel are deflected out an escape hatch. As sea turtles are air-breathing, they must come to the surface every hour or so. Without a TED, they are trapped in a net for as long as it is towed underwater and sometimes drown before being brought aboard. | |