The reduction in amount or elimination of pollution

Abdominal Pelvics

The pelvic fins located at the far rear of the abdomen, behind the pectoral fins

Acid Rain

Rainfall with a pH level of 7.0 or less. Long-term effects of acid rain is linked to adverse effects on aquatic organisms and plant life in areas with poor neutralizing (buffering) capacity, which can eventually lead to the “death” of a lake or similar body of water. Limestone-based lakes naturally buffer the acidity, for example.

Adipose Eyelid

A thick, fleshy transparent tissue that covers tissue around the margin of the eye of some fish.


The active or passive process by which water is oxygenated, generally by spraying water in the air, bubbling air through water, or mechanically agitating the water to ensure the surface absorption of air.


A piece of equipment designed to provide oxygen to water, usually within a live well or container holding game or bait fish to ensure the water is oxygenated to sustain fish. Generally aerators are pumps that flow oxygen or splash water. See also: Live well and Oxygen Level of Water.


A term referring to the rear or stern of a boat

Air Boat

Essentially a flat-bottomed vessel propelled in a forward direction by an aircraft-type propeller and powered by either an aircraft or automotive engine. The engine and propeller are enclosed in a protective metal cage that prevents objects such as tree limbs, branches, clothing, beverage containers or wildlife from coming in contact with the whirling propeller.

Albright Knot

A fishing knot used for making line-to-line connections


Term refering to a very large and diverse group of aquatic organisms that do not possess root systems, leaves or stems and can range from single celled freshwater organisms to more complex varieties of saltwater kelp. Algae is a critical component of the aquatic food chain, needed to sustain marine life. See also: Plankton, Phytoplankton and Zooplankton.

Alien Species

A species, not necessarily related to marine life, outside of it’s natural or historical habitat. Sometimes referred to as “introduced” species, this is often done accidentally or unintentionally with unwanted species, as in the case of the introduction of Zebra Mussels into smaller lakes from boats and trailers.


This is the capacity of solutes in an aqueous system to neutralize acid. PH above 7 is consider acidic and below seven is considered base. Most fish prefer a neutral PH around 7

Anadromous Fish

These are fish that migrate from the saltwater oceans and seas to spawn in freshwater rivers and streams.

Anal Fin

The single fin located directly behind the anus.


Maintaining the position of a boat in a body of water, such as a river, lake, ocean or stream, through the use of a heavy object fixed to the water bottom, usually of heavy metal secured to a line or chain. There are numerous types of anchors, such as mushroom, danforth, navy and grapnel.


Someone who fishes, primarily referring to fishing with hooks.


The act of catching or trying to catch fish for personal use, fun, challenge and leisure using sporting equipment.


The point in the moon’s orbit farthest from the Earth, producing a lower tidal range.


The farming of freshwater and saltwater organisms. Unlike fishing, aquaculture, also known as aquafarming, implies the cultivation of aquatic populations under controlled conditions.


A type of drill for boring holes in the ice.

Axillary Process

A fleshy flap that is usually narrow and extends to the rear, situated just above the pectoral or pelvic fins on some fish.


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