Overview
The first major
Fisheries Habitat Condition and Trend Report for
Queensland was published in 1998.
The Fisheries Group of
the Department of Primary Industries has published
Queensland's Fisheries Habitats, Current Condition and
Recent Trends - the first report of its kind on
the condition of habitats that sustain Queensland's
important fishing and aquaculture industries.
The report is the first
in a series that will provide regular updates of the
condition and trend of major Queensland habitats that
support the State's fisheries.
It brings together
information on the current documented changes in
habitats supporting major fisheries including
freshwater streams and riparian zones, mangroves,
seagrass, saltmarsh and coral reefs. It also
highlights fishery habitats where more information is
required to assess changes.
The report is a major
step forward in bringing together information on
pressures affecting freshwater, estuarine and marine
fisheries habitats and their current condition.
Recent surveys of
riparian vegetation, melaleuca forest, tidal wetlands
and seagrass have shown different levels of change due
to natural and man-made causes including losses of
some habitats in some areas.
It is important that we
understand these changes and how they impact on fish
stocks worth more than AUD 250 million to Queensland's
economy each year.
Fishery habitat
monitoring and Statewide reporting of changes to
fishery habitats are important functions undertaken by
DPI to provide up-to-date information to Queensland's
fisheries managers and fishing industry groups to
allow enhanced management of these habitats.
It is envisaged that
the report will prove a valuable reference for all
groups interested in the sustainable use of our
streams, estuaries and sea including fishers,
community groups, local councils and State Government
Departments.
A summary of the report
appears below.
Executive summary
Freshwater, estuarine
and marine habitats are fundamentally important to
recreational, commercial and traditional fisheries and
are necessary for the survival, growth and
reproduction of fisheries resources (e.g. fish,
prawns, crabs, crayfish and oysters). Diversity of
habitat types is essential to maintain diverse and
productive fisheries resources.
Freshwater plants
including algae, macrophytes, bank trees; physical
structures within stream channels (e.g. woody snags,
bank overhangs and boulders) and flow characteristics
(e.g. pools, riffles or waterholes) are elements
without which freshwater fisheries diversity and
production become limited.
Marine plants including
mangroves, saltmarsh seagrasses and algae; physical
structures (e.g. coral and rocky reefs, sandbanks,
channels and tidal flats) and water characteristics
(e.g. shallow sheltered estuaries and deep oceanic
waters of the continental shelf and slope) are
elements that support diverse and productive estuarine
and marine fisheries.
Both vegetated and
non-vegetated habitats are necessary for production of
a number of important fish, prawn and crab species
supporting major fisheries. The interaction of
habitats with other fishery resources requires further
research to be better understood. With our current
state of knowledge of processes, human modification of
non-vegetated habitats (e.g. sand and gravel bars and
tidal flats) should be viewed with considerable
caution. Changes to these habitats may cause long-term
losses or decline in abundance of associated fishery
species.
Queensland's fisheries
habitats are affected by natural variability at a
range of scales in space and time. Environmental
factors may cause changes in habitats on a broad-scale
(e.g. the enhanced greenhouse effect and El Niño),
regional scale (e.g. cyclones and changes to ocean
currents) or local scale (e.g. natural succession in
foreshore vegetation patterns and flood changes to
river bed, banks and bars). Fisheries habitats also
change in response to these and other environmental
factors over daily, seasonal, year-to-year or longer
time scales. Among the effects of variability in
habitat, there may be changes to levels of fisheries
production (mix of species and quantity of catch)
although the pattern of the response for most fishery
species is unpredictable with our current level of
knowledge.
In addition to
environmental factors, pressures from human activities
are applying increasing levels of stress to fisheries
habitats. Demand for water for agricultural, urban and
industrial uses is impacting stream habitats. Streams
are also subject to heavy pressure.
Reduced spawning is
considered a major threat to some fishery stocks
especially where generalised degradation of fishery
habitat occurs on a catchment-wide scale or where
recognised spawning sites are disturbed by human
activity or habitat modification. Specific locations
and habitat requirements for spawning have been
identified for a number of major fishery species.
Major areas of
important habitat supporting fisheries in estuarine
and marine waters throughout Queensland are protected
to varying levels from disturbance in declared Fish
Habitat Areas, the Great Barrier Reef Marine Park and
State Marine Parks. Freshwater habitats currently have
some protection in the relatively small area managed
as estate areas (e.g. National Parks) and Forestry
reserves but are heavily impacted by agricultural and
urban land use in other areas.
Community and industry
participation in management of stream catchments for
sustainable use (e.g. Integrated Catchment Management)
recognises the increasing need for stakeholder action
to protect fragile habitats supporting productive
freshwater and coastal fisheries.
There is a recognised
need for improved long-term monitoring of the
condition and trend of habitats supporting
Queensland's fisheries. Selection of the best
indicators for long-term monitoring is currently at a
developmental stage. The indicators used in this
report largely reflect existing monitoring programs of
human activities (pressures) that have the potential
to impact upon fisheries habitats and cause adverse
changes to their capacity to support productive
fisheries.
Overall, freshwater
habitats are in good condition in Cape York Peninsula,
in a few relatively small areas of the east coast and
in National Parks. Medium to high levels of change
attributable to human disturbance have occurred in
fisheries habitats over much of the remaining
freshwater areas and are likely to continue. Estuaries
and inshore habitats are under increasing pressure
from human activity near urban centres in southern
Queensland, industrial centres in central and southern
Queensland and areas of intensive agriculture in the
Wet Tropics. Offshore habitats are generally less
susceptible to the impacts of mainland activity.
However, continued trawl fishing on the continental
shelf and increasing tourist access to the outer Great
Barrier Reef may cause long-term changes to habitats
required by some fishery resources.
This is the first time
a Statewide report of the current condition and recent
trends in major fisheries habitats has been produced.
Comments on the report are welcome and may be sent to:
The General Manager
Fisheries Policy and Sustainability
Queensland Fisheries Service
Department of Primary Industries
GPO Box 46
BRISBANE QLD 4001
For general information
contact the
DPI Call Centre on 13 25 23.
Specific questions on
technical aspects may be addressed to the author Mr
Brad Zeller or Dr Malcolm Dunning, Assessment and
Monitoring Unit, at the above address.
Obtain a copy of the report
Copies of the report
are available from the Assessment and Monitoring Unit,
DPI Fisheries, GPO Box 46, Brisbane, QLD, 4001.
Brad Zeller
Fisheries Resources Officer, Assessment and Monitoring
Unit
(Phone: 07 3224 2236) |
