Underwater breathing device consisting of an on-board air compressor and an air supply tube to a diver\'s mouthpiece or helmet.
Farming; management and control of a proprietary stock.
Any enclosure or facility used to restrict the movement of fish stocks, whether in natural or artificial environments.
index of abundance
A relative measure of the abundance of a stock; e.g. a time series of catch per unit of effort data.
individual transferable quota
A management tool by which the total allowable catch, TAC quota is allocated to individual fishers or companies. These individuals or companies have long-term rights ...
Indirect restraints on amount of fish caught, by way of management controls on type and/or amount of fishing; e.g. by gear restrictions, closed seasons; see also output controls ...
Waters of the shallower part of the continental shelf; see also nearshore waters.
instantaneous rate of fishing mortality
When fishing and natural mortality act concurrently, F is equal to the instantaneous total mortality rate, multiplied by the ratio of fishing deaths to all deaths. Also ...
instantaneous rate of growth
The natural logarithm of the ratio of final weigl1t to initial weight of a fish in a unit of time, usually a year. When applied collectively to all fish of a given age in a ...
instantaneous rate of mortality
The natural logarithm (with sign changed) of the survival rate. The ratio of number of deaths per unit of time to population abundance during that time, if all deceased fish ...
instantaneous rate of natural mortality
When natural and fishing mortality operate concurrently it is equal to the instantaneous total mortality rate, multiplied by the ratio of natural deaths to all deaths. Also ...
instantaneous rate of recruitment
Number of fish that grow to catchable size per short interval of time, divided by the number of catchable fish already present at that time. Usually given on a yearly basis: that ...
instantaneous rate of surplus production
Equal to rate of growth plus rate of recruitment less rate of natural mortality--all in terms of weight and on an instantaneous basis. In a "balanced" or equilibrium fishery, ...
The region of land which is submerged during high tide and exposed during low tide.