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Government of Western Australia - Department of Fisheries

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A sudden and violent shaking of the ground, sometimes causing great destruction, as a result of movements within the earth's crust or volcanic action. The intensity of earthquakes is expressed by the Richter scale (1 – 10).

Ebb tide
Receding or outgoing tide.

A Phylum of animals with radial symmetry, spiky or rough skin (echino – spiky; derm – skin) and locomotory tube feet. Examples include sea stars, sea cucumbers and sea urchins.

Echo sounder
Device used on fishing boats to determine water depth, bottom type, bottom gradient and the presence of fish.

Study of the relationships of animal and plant communities to their surroundings both living and non-living.

Economically viable
Able to make money (out of a resource, business, etc.)

Ecologically Sustainable Development (ESD)
Using, conserving and enhancing the community’s resources so that ecological processes, on which life depends, are maintained, and the total quality of life, now and in the future, can be increased.

A complex set of relationships among the living resources, habitats and residents of an area.

Ecosystem integrity
The capability of an ecosystem to support ad maintain key ecological processes and organisms.

The ability of an organism to regulate its body temperature via exchange of heat with its surrounding environment; referred to as cold-blooded.

A water (or air) current moving against the direction of the main current, especially in a circular motion, i.e. whirlpool.

See Exclusive Economic Zone

Amount of time spent fishing by a given group of fishers.

Effort restriction
A type of input control used a management tool whereby the amount of fishing effort expended by fishers in a particular fishery is restricted by law.

See Environmental Impact Assessment

A class of fishes marked by cartilaginous nature of the bones and the absence of sutures in the cranium, such as sharks, rays and sturgeon.

Indentation of a coastline to create a bay or bay-like formation, larger than a cove but smaller than a gulf; also called a drowned river valley.

Stage of an organism before birth or hatching; underdeveloped.

Environmental Management Strategy

At a very high risk of becoming extinct.

A species that occurs only in a confined area; referred to as a native species.

Organisms that generate body heat above ambient temperatures through various physiological and anatomical specialisations.

The capacity for activity made possible by the metabolism of food that originally acquired the energy from sunlight.

To ensure observance of laws and rules.

A planned process with the specific purpose of working with identified groups of people, whether they are connected by geographic location, special interest, or affiliation, to identify or address issues affecting their well-being.

The living things, their physical, biological and social surroundings, and interactions between all of these.

Environmental Impact Assessment
A process carried out by the Environmental Protection Authority for evaluating a proposal, including its alternatives and objectives, and its effect on the environment, including the mitigation and management of those effects.  The process extends from the initial concept of the proposal through implementation to commissioning and operation and, where appropriate, decommissioning.

Environment Protection and Biodiversity Conservation Act 1999

Short-lived, often seasonal.

Invertebrate animals living on the surface of the seabed.

An organism that lives on the surface of another organism.

The point on the Earth's surface directly above the focus of an earthquake.

Animals that live on the surface of the substrate.

The epipelagic is the zone from the surface down to approximately 200m in depth.

Plants that attach themselves to the stem or leaves of plants.

An imaginary line around the earth equidistant from the poles, dividing the earth into two equal symmetrical parts, i.e. Northern and Southern Hemispheres.

Environmental Risk Assessment

The removal of all the individuals of a particular species (animal or plant) from a given environment.

Wearing away of a shoreline by constant wave action.

See Ecologically Sustainable Development

To set up or secure permanent existence.

Of, relating to, or found in an estuary

That part of the mouth or lower course of a river in which its current meets the sea’s tides.

Estuarine crocodile (Crocodylus porosus)
Largest of all living reptiles found in suitable habitats in Northern Australia, the eastern coast of India and parts of Southeast Asia. Also referred to as saltwater crocodile.

Adapted to live in a wide range of salinities.

Euphotic zone
Upper part of the photic zone where most photosynthesis occurs.

The process of enrichment of water with nutrients that increase plant growth and generally resulting in depletion of dissolved oxygen. A natural process that can be caused/enhanced by an increase in nutrient loads or decreased flushing rates resulting from human activity.

Convert or change into a vapour.

A change in the genetic makeup of a species, usually as a result of natural selection favouring some individual characteristics over others.

Exclusive Economic Zone
A generally 200-nautical-mile zone declared in August 1994 by Australia in line with the provisions of the United Nations Convention on the Law of the Sea. Australia has the right to explore and exploit, and the responsibility to conserve and manage, the living and non-living resources within this area; cf. Australian Fishing Zone.

A hard outer structure or external covering, such as the shell of crustaceans, that provides protection or support for the organism.

The act of being fished, harvested or put to use.

Fished; harvested or put to use.

Extensive Aquaculture
Low intensity aquaculture which usually takes place in dams, ponds, or lakes. Characterised by low stocking densities, low supplementary feed rates and high levels of natural food production.

External territory
A country’s territory that lies outside its mainland, usually geographically isolated.

When there are no more living representatives of a species; died out.


Last modified: 27/11/2012 11:44 AM

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