lake can be sectioned into large portions known as "lake
zones". These zones are not easily defined and indeed are
very generalized in comparison to geographic features such as
break lines, channels and flats.
The three main zones of a lake are:
Littoral Zone. The lakes littoral zone is the area around
the lake edges where sunlight penetrates to a depth where aquatic
plant life (water weed and phytoplankton) are no longer present.
The aquatic weed and phytoplankton are the basis of the aquatic
foodchain which supports the most diverse life forms ranging from
aquatic plant life, zeoplankton, crustacean and fish.
Zone. The centre of a large lake basin is not dissimilar to
the middle of an ocean. Water depths are great and there is no
significant structure near the water surface. Aquatic life is
adapted to suspending or floating on or near the surface of the
lake. Small plankton build up significant numbers to create the
base of another foodchain with ultimately larger fish species
at the top.
Benthic Zone. Only a few organisms are capable of premanent
residency in this zone. Due to lack of oxygen and light at these
depths the aquatic weed and fish life are non existent. There
are some organisms that assist in the decomposition of dead matter
that finds its way down to these dark depths.
East Queensland has seasonal weather patterns that are generally
predicatable such as wet and dry seasons, as in many other parts
of Australia. Impoundments were built as important water storage
facilites for rural or domestic use. As consumers, we have regular
patterns of water consumption, water levels are controlled or
manipulated by the water board who monitor and distibute the resource
accordingly. A dams water level will rise and fall periodically
over a season and in some instances it may remain static for several
months or years.
The volume of influx (water coming into the catchment) versus
consumption (water being taken out by consumers) affects mainly
the littoral zone. The lakes littoral zone is the most transient
of all three zones, the area around the lakes edges ebbs to and
fro with water levels significantly altering fish habits.
littoral zone is seldom static due to changing water levels, and
it is this major factor that reflects how anglers fish a dam.
Basically many impoundments will fish differently in high water
conditions and in low conditions.