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See Total Allowable Catch
Total Allowable Commercial Catch
Total Allowable Effort
Total Allowable Recreational Catch
Target catch
Catch that has been selected by species or size.  Generally the highest ‘value’ catch available.  Value can be determined in terms of dollar return, size, eating or sportfish quality or social significance.
Tar spot
A packet of sperm transferred from the male than carried by a female lobster on the underside of the carapace, between the hindmost pair of legs, to fertilise eggs.
Taxonomic group of organisms (of any rank, e.g. species, genera, family) considered to be distinct from other such groups.
The science of classification according to a pre-determined and ordered system.
Tectonic plate
A segment of the Earth’s crust that moves, floats, and sometimes fractures and whose interaction causes continental drift, earthquakes, volcanoes, mountains and oceanic trenches.
Turtle Exclusion Device
Extension of the body in the centre of the of the tail fan (uropods) of lobsters, prawns, marron etc.
In the southern hemisphere, seas that lie between the Antarctic and the Tropic of Capricorn.
Pertaining to time.
Temporal closure
Closure over time, for example a seasonal closure.
Tertiary consumers
An animal that gets its energy from secondary consumers.
Territorial sea
The area of sea adjacent to Australia which extends beyond its land territory and internal waters.  Australia’s territorial sea extends to 12 nautical miles from the baseline.
The body of a macroalgae, made up of the blade, stipe and holdfast.
Two layers of water in the ocean that consists of warm, less dense water on top and, dense colder water underneath.
Involving or dependent upon the combined effect of temperature and salinity, such as thermohaline circulation.
An indication of imminent harm, danger or menace.
A species or community that is vulnerable, endangered or presumed extinct.
Tidal bore
A wave (or waves) of water formed on the incoming tide that travel up a river or estuary.
Tidal force
Secondary effects of the force of gravity, responsible for the tides.
Tidal period
Interval of time between two consecutive like-phases of the tide, i.e., two consecutive high or low tides.
Tidal range
Difference in height between consecutive high and low tides.
The rhythmic rise and fall of the sea level caused by the gravitational pull of the moon and sun and by the centrifugal force caused by the rotations of the earth, moon and sun.
Total allowable catch
The total amount of fish (by weight or number) that can be safely removed from
fishery each year without causing the population to decline over time.
Total length
Length of a fish measured from the tip of its snout to the most distal tip of its caudal (tail) fin.
A poisonous substance produced by living cells or organisms; a biologically produced poison.
The capture, transport and release or introduction of species or other ecological material from one location to another.
Trap fishing
Fishing by means of traps, often designed to catch a particular species, e.g. rock lobster pots.
Trash fish
An expression used by fishers to describe discarded catch that has no commercial value.
A method of fishing in which large nets are towed behind one or more boats
A long, narrow and very deep depression in the ocean floor (subduction zone).
Fishing method of drawing bait or lures along the water.
Predator-prey relationships.  Connected with nutrition and feeding.
In the southern hemisphere, the seas that lie between the Equator and Tropic of Capricorn.
Clouded, not clear or transparent, because of stirred-up sediment or particles suspended in the water
The amount of solid particles that are suspended in water and that cause light rays shining through the water to scatter. Thus, turbidity makes the water cloudy or even opaque in extreme cases. Turbidity is measured in nephelometric turbidity units (NTU).
Aquatic or terrestrial reptiles, with webbed feet or flippers and a bony or leathery shell.


Last modified: 11/09/2012 11:47 AM

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