estuaries brochure 2

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 near pristine estuaries
                                                                                          TOM ULRICH, AUSCAPE.

             Understanding Australian estuaries
             The first stage of the Australia-wide estuary condition assessment
             has made a preliminary classification of the condition of 970
             estuaries in Australia. The estuaries that were classified as near
             pristine are the focus of this summary report.

             Definition of an estuary
             This assessment broadly defines an estuary as a ‘semi-enclosed
             coastal body of water where salt water from the open sea mixes
             with freshwater draining from the land’. The estuaries included
             in the assessment were selected according to management interest
             rather than a strict scientific definition.

             Types of estuaries
             Tides, waves and river flows are important physical processes that
             influence estuary estuary shape and ecology. Estuaries can be
             categorised into three types based on the relative dominance of
             these physical processes.
                                                                                                   Identifying near pristine estuaries
                                                                                                   An estuary was classified as near pristine if it had:
                                                                                                          • a high proportion of natural vegetation cover in the
                              River                                                                       • minimal changes to hydrology in the catchment
                                                                                                          • no changes to tidal regime
                                                                                                          • minimal disturbance from catchment land use
                                         PHYSICAL                                                         • minimal changes to floodplain and estuary ecology

                                                                                                          • low impact human use of the estuary
                                                                                                          • minimal impacts from pests or weeds

                                                         Wave                                      The other three categories of the assessment—largely
                                                                                                   unmodified, modified and severely modified—display increasing
                                                                                                   levels of changes for some or all of these key criteria.

             Each estuary type has distinct characteristics, susceptibility to                     Asessment findings
             impacts and management requirements. All Australian estuaries
                                                                                                   Most of Australia’s near pristine estuaries are located away from
             in this assessment are being classified according to their dominant
                                                                                                   population centres in tropical northern Australia and temperate
             biophysical processes. This classification will be used as a
                                                                                                   western Tasmania. Important near pristine estuaries are also
             framework for management.
                                                                                                   found around the developed areas of Australia, often within or
             Values of near pristine estuaries                                                     near to managed public lands such as national parks and state
             Near pristine estuaries are valuable as:
                                                                                                   Australian estuaries were found to be:
                    • habitat for native plants and animals—important for the
                                                                                                          • 50% near pristine
                      conservation of biodiversity
                                                                                                          • 22% largely unmodified
                    • environments that support commercial, traditional and
                      recreational fisheries and tourism                                                  • 17% modified
                    • places for recreation and wilderness experiences                                    • 11% severely modified
                    • benchmarks for estuary management                                            The near pristine estuaries map (facing page) illustrates the
                                                                                                   results of the qualitative condition assessment of estuaries.


                                                                                                   Estuaries are young, dynamic zones of diversity, production,
                                                                                                   confusion and conflict in the forces of nature, culture and law. They
                                                                                                   buffer extreme energies of wind and tides, drought and flood, to strip
                                                                                                   and settle sediments and nutrients, shelter life and limb, and kick-
                                                                                                   start food chains. Competition between our demands and the forces
                                                                                                   of river and sea will ultimately govern their form and function.
                                                                                                           Mike Cappo, Australian Institute of Marine Science, 2000

 Australia-wide Estuary Condition Assessment                             n   a p a r t n e r s h i p b e t w e e n C o m m o n w e a l t h , S t a t e a n d Te r r i t o r y a g e n c i e s
                                                                    A RO U N D
            Estuaries from each of the States and Northern Territory reflect the diversity of the Australian landscape. In the following section of this brochure,
            values of near pristine estuaries from each region in Australia and issues for their management are briefly mentioned. The coloured bar represents
            the condition of all the estuaries in that State, and the number to the right of the bar and its relative length is the total number of estuaries in the

ENVIRONMENT,TASMANIA.                                                                                     South Australia                                                        34
                                                                                                          South Australia’s rainfall is low; hence the majority of South
                                                                                                          Australian estuarine systems are tide-dominated. South Australia’s
                                                                                                          major river—the Murray—has been regulated to meet
                                                                                                          development needs affecting downstream estuarine systems.
                                                                                                          Estuaries in this State are threatened by coastal development and
                                                                                                          commercial and recreational activities. Not only does this State
                                                                                                                  have few estuaries in total, very few of those are
                                                                     SIM WARD.
                                                                                                                  considered to be near pristine.
                                                                                                                  Some estuaries in South Australia are more correctly
                                                                                                                  identified as ‘embayments’. These systems have important
                                                                                                                  fisheries and conservation values. South Australia is
                                                                                                                  undertaking a management-oriented inventory and it is
                                                                                                                  likely that the embayments will be added to the
                                                                                                                  Australian database.
                                                                                                                  The small wave-dominated estuary ‘lagoon’ at the mouth
                                                                                                                  of Breakneck River on Kangaroo Island, is the only South
                                                                                                                  Australian estuary whose catchment is totally included
                                                                                                                  within a national park—the Flinders Chase National
                                                                                                                  Park. The conservation role of this park is of prime
                                                                                                                  importance in maintaining water quality. Visitors are
                                                                                                                  encouraged to use and enjoy the area according to the
                                                                                                                  principles and objectives set by the 1999 Flinders Chase
            Tasmania                                                              125
                                                                                                                  National Park Management Plan.

            Catchments in the west, north-west and south of Tasmania are                                  Contact:    Patricia Carvalho
            characterised by high rainfall and run-off, while catchments in                                           08 8204 2139,
            the east and north-east are relatively dry. North coast estuaries are
            tide-dominated barrier estuaries.They are open to the sea and
            have much greater tidal ranges than estuaries on the southern,                      BREAKNECK RIVER ESTUARY, KANGAROO ISLAND, SOUTH AUSTRALIA. DEPARTMENT OF ENVIRONMENT
            eastern and western coasts. The east coast and Bass Strait estuaries                AND HERITAGE,MAPLAND.

            are intermittently closed by sand barriers and are therefore wave-
            The majority of near pristine estuaries in Tasmania are located in
            the south and west of the State and on Cape Barren Island in the
            Furneaux Group. These estuaries are valued for nature
            conservation, wilderness and recreation.
            Approximately 50% of near pristine estuaries in Tasmania are
            located in national parks. Although this partially protects their
            adjacent aquatic environments, further ways to protect aquatic
            life and other environmental values of these estuaries need to be
            developed to minimise threats. These threats include (but are not
            limited to):
                  • siltation resulting from land clearance
                  • modification of hydrology through dams and weirs
                                                                    ERIC ANDERSON.
                  • habitat disturbance through foreshore
                  • introduction and spread of introduced
                    pest species

            Contact: Gwen Fenton
                     03 6233 3521,

  E s t u a r i e s a re key mu l t i - v a l u e re s o u rc e s . M a ny o f u s l i ve , f i s h o r b o a t o n t h e m , o r s i m p l y ap p re c i a t e t h e i r d i ve r s i t y a n d d y

                                                                                                                                               YAFFA PUBLISHING GROUP.

               Western Australia                                                           166                       Northern Territory                                                          140
               Western Australia has a diverse range of estuaries.                                                   The estuaries on the northern, Arnhem Land and Gulf of
                                                                                                                     Carpentaria coasts are predominantly tide-dominated barrier
               Northern Western Australia has tidal ranges of more than 10 m
                                                                                                                     estuaries, which vary greatly in size and floodplain characteristics.
               and estuaries in this region are tide-dominated. Monsoonal
                                                                                                                     Tides range up to 7–8 m and freshwater input to all estuaries is
               rainfall also has a seasonally important influence on the ways
                                                                                                                     strongly seasonal. Floodplain wetlands are associated with most
               these estuaries function. Extreme heat and evaporation cause
                                                                                                                     large estuaries.
               stunted growth in estuary-associated vegetation such as
               mangroves, but little more is known about the natural processes                                       Northern Territory estuaries are valuable for traditional
               driving these estuaries.                                                                              harvesting, eco-tourism, pearling, and commercial and
                                                                                                                     recreational fishing. The Cobourg Marine Park (contiguous with
               Near pristine estuaries in this area are important for cultural
                                                                                                                     Gurig National Park) protects the biologically diverse Cobourg
               values, pearl aquaculture, commercial and recreational fishing,
                                                                                                                     Peninsula and includes many small estuaries.
               safaris, and eco-tourism.
                                                                                                                     Estuaries along the Gulf of Carpentaria, in addition to the above
               Further research is needed to identify potential threats and to
                                                                                                                     uses, also play an important role in supporting prawn and finfish
               make specific recommendations on how to maintain and manage
                                                                                                                     fisheries. The number and diversity of near pristine estuaries in
               these estuaries in near pristine condition.
                                                                                                                     the Northern Territory provide reference sites and research
               Central-northern and southern Pilbara estuaries are both wave-                                        opportunities to better understand modified tropical estuaries.
               and tide-dominated.                                                                                   The major estuaries on this coast provide significant habitat for
                                                                                                                     one of the densest populations of saltwater crocodiles in the
               Near pristine estuaries in this region are valued for nature
                                                                                                                     world, and roosting areas for sea and water birds.
               conservation and eco-tourism. Eco-tourism needs to be well
               managed to maintain the values and condition of these estuaries.                                      Catchment and shoreline development can pose a threat to near
                                                                                                                     pristine estuaries. Sediment loading to estuaries will increase if
               The south-western and southern coasts of Western Australia have
                                                                                                                     natural vegetation is not maintained.
               tidal ranges of 0.5–1 m and are wave-dominated. Some estuaries
               are seasonally-closed and some remain permanently open. The                                           Contact: Simon Townsend
               Mediterranean climate and rainfall pattern in this region results                                              08 8999 3413,
               in a floristically rich coastal heath and extensive forests in the
               wetter areas of the south-west corner.
               Broke inlet at the mouth of the Shannon River is the only estuary
               in near pristine condition in this region. It is a large lagoon and is
               connected to the sea by a long, narrow channel through coastal
                                                                                                           JEAN-PAUL FERRERO, AUSCAPE.
               dunes. The estuary is located entirely within the D’Entrecasteax
               National Park which extends along the coast.
               Broke Inlet has many conservation values and is also important
               for recreational and commercial fishing. The inlet is geologically
               similar to many estuaries on the south coast, making it useful as a
               benchmark to compare with problems of nutrient enrichment
               and sedimentation within other inlets and estuaries.

               Contact:      Malcolm Robb
                             08 9278 0526,

y n a m i c l a n d s c a p e s . U n f o r t u n a t e l y m a n y e s t u a r i e s a r e s u b j e c t t o s y s t e m i c d e c l i n e . T h e c o n d i t i o n o f A u s t r a l i a ’s e s t u a r i e s a n d
                                                                                     BAFFLE CREEK, QUEENSLAND.WAYNE LAWLER, AUSCAPE.

           Queensland has a long coastline containing many near pristine
           The Gulf of Carpentaria coast is flat with a large area of
           mangroves and salt pans which becomes a contiguous wetland
           complex during the wet season. The estuaries here are tide-
           Near pristine estuaries in the Gulf of Carpentaria provide
           essential nursery habitat for prawns and finfish, supporting major
           commercial, recreational and traditional fisheries. On-going
           management to ensure the sustainability of these fisheries is
           required. Other values are conservation of biodiversity, cultural
           uses and safari-based eco-tourism.                                                      YAFFA PUBLISHING GROUP.

           Cape York has mostly tide-dominated barrier estuaries
           interspersed with small wave-dominated estuaries. There are also
           some seasonally river-dominated estuaries.
           Near pristine estuaries on Cape York are important for
           conservation of biodiversity. They support endangered and
           vulnerable biota such as turtles, dugongs, and crocodiles. Other
           important values include:
                  • indigenous cultural uses
                  • safari-based eco-tourism
                  • commercial prawn and finfish fisheries
           Eco-tourism, and commercial and recreational fisheries must
           copntinue to be well managed in order to protect the values of
           near pristine estuaries. Protection measures need to involve all
           stakeholders and become an integral part of the Cape York                         The current coastal management system is the cause of the failure to
           Peninsula Land Use Strategy.                                                      redress the problem of the coastline. This management system is
                                                                                             characterised by fragmentation of responsibility between spheres of
           Southern and central Great Barrier Reef lagoon coasts have a
                                                                                             governments, among different professional areas of expertise, and
           broad spectrum of river, tide and wave-dominated estuaries.
                                                                                             across different social, economic and environmental interests. It is
           Near pristine estuaries are important resources that support                      indeed difficult for the existing system of coastal management to
           commercial and recreational fisheries, and have recreation, nature                become part of the solaution to coastal degradation while it remains
           conservation and wilderness values.                                               part of the problem.
           The Great Barrier Reef Marine Park World Heritage Area, the                          Valerie Brown, Centre for Resource and Environmental Studies
           Wet Tropics World Heritage Area, coastal and island national                                                   Australian National University, 1995
           parks, and the Shoalwater Bay Military Training Area protect              STATE OF QUEENSLAND.
           several small estuaries and their catchments. Seventy-five Fish
           Habitat Areas (protecting key areas of fish habitat) are also
           strategically distributed along the Queensland coast.
           One of the few near pristine estuaries in south-east Queensland is
           located at the mouth of Baffle Creek. Although its catchment has
           high integrity, the estuary still needs management in order to
           maintain its near pristine values. Baffle Creek is currently under
           consideration as a Fish Habitat Area and it is expected that a
           formal declaration will be achieved by mid-2000.

           Contact:     David Robinson
                        07 3869 9503,
                                                      STATE OF QUEENSLAND.


their      floodplains         provides        the    litmus       test       for   catchment       management.              Estuaries       are     the     sinks,   rece
                                                                                 MALLACOOTA ESTUARY,VICTORIA. CAMERON MILLER, MARINE SCIENCES, EPA,VICTORIA.

         New South Wales

         Northern New South Wales has tide to river-dominated barrier
         estuaries with extensive floodplains, interspersed with a series of
         wave-dominated coastal creeks and lagoons. Many of these wave-
         dominated systems have ephemeral entrances where longshore
         sand drift closes entrances between periods of high freshwater
         Several of the smaller estuaries (e.g. Lake Aragan with its
         ephemeral entrance lagoon, and Sandon River, a barrier estuary)
         are wholly within national parks.The central coast of New South
         Wales, while still containing barrier estuaries and lagoons, is
         noted for its drowned river valleys (e.g. in the lower Hawkesbury
         River, Sydney Harbour and Port Jackson).                                         Victoria                                                             61
         Most of the estuaries of New South Wales are under intense land
         use pressure with approximately 80% of the State’s population                    Victoria has many small estuaries that are either river or tide-
         living near an estuary. Most of the State’s estuaries are also                   dominated barrier estuaries, or small wave-dominated lagoons.
         considered modified as a consequence of this pressure and there                  The entrances to these estuaries are usually ephemeral. Two large
         are conflicts within local communities over the use of this limited              embayments (Western Port and Port Phillip Bay) and the
         resource. The NSW Estuary Management Program was                                 Gippsland Lakes (an interconnected lake system with an entrance
         introduced in 1992 to help resolve these conflicts and to provide                to the coast) are also included in the assessment for management
         technical and financial assistance to local governments, so that                 purposes.
         they could prepare and implement sustainable estuary
         management plans. The NSW Estuary Management Manual 1992                         Estuaries in western and central Victoria are modified to varying
         was compiled to assist managers to address critical estuary                      degrees by urbanisation, and industrial, agricultural and forestry
         management issues. Sound estuary management has developed as                     activities in the adjoining catchments. Many of the small
         a result of these initiatives.                                                   estuaries in eastern Victoria are located within national parks and
                                                                                          are in near pristine condition. These estuaries are valuable as
         On the northern coast, resolution of conflict over resource use                  native conservation and wilderness areas.
         has included debate over the management of acid sulfate soil run-
         off (which can result in fish kills), restoration of drained coastal             Mallacoota Inlet is an estuary in near pristine condition that is
         wetlands, recreational boating and fishing, aquaculture and oyster               being studied in detail to provide a benchmark for other more
         farming, commercial fishing, sand extraction, and entrance                       modified estuaries.
         shoaling.                                                                        Contact: Andrew Steven
         The few remaining near pristine estuaries in southern New South                           03 9616 2353,
         Wales are generally located adjacent to or within land of public
         tenure (e.g. national parks or State forests). Their location away                          WAYNE LAWLER, AUSCAPE.
         from areas of intense development pressure and on public land,
         means that most will be able to be sustainably managed into the
         future. These near pristine estuaries also provide important
         benchmarks for measurement of the condition of modified
         estuaries and in helping to design cost-effective remedial
         Key near pristine systems in southern New South Wales include
         Meroo, Willinga, Durras, Termeil, Nelson’s and Nadgee lakes.
         Most of these lake systems have national park and State forest
         lands within their catchments and are managed for nature
         conservation as well as other uses. Many park boundaries do not
         specifically include associated or adjacent estuaries. However the
         values of these estuaries need to be recognised and managed as an
         ecologically important public resource.

         Contact:   David Miller
                    02 9895 7485,


                                                                                KHAPPINGHAT ESTUARY, NEW SOUTH WALES. NSW DEPARTMENT OF LAND AND WATER CONSERVATION.

eiving   the   impact       of    catchment          land      use:     sediments,     nutrients,         poisons         and      changes         in    water      f l o w.

Management needs
Near pristine estuaries and their catchments require protection        government and agencies also make management complex. This
and careful management.                                                is compounded by the various values held and uses demanded by
                                                                       the community.
Catchment protection and management should ensure that land
use does not deleteriously impact on waterways or estuaries.           A lead agency within each State, and attention to how the roles
Estuary use also requires management including:                        and responsibilities of all tiers of government and their agencies
     • declaration of protective zones (e.g. fish habitat areas or     are accomodated, would facilitate improved estuary management.
       marine national parks)
                                                                       •   Specific policy
     • active management including extension, licencing, patrol
                                                                       In recent years, a range of initiatives at local, State and
       and enforcement activities for uses such as tourism,
                                                                       Commonwealth government levels have addressed the needs of
       commercial and recreational fishing
                                                                       waterways, coasts and oceans. An Australia-wide policy and
Regional planning is essential and provides the context for            management initiative for estuaries is essential.
developing appropriate management arrangements in
                                                                       The role, breadth and implications of such a policy will be
consultation with community and industry.
                                                                       explored as the assessment of Australia’s multi-use, modified
Restoration of an estuary and its catchment is expensive.              estuaries progresses.
Protective management is more cost-effective in the long term.
                                                                       •   Community and industry involvement
Institutional arrangements                                             Government alone will not fulfil estuarine management needs.
                                                                       All natural resource management involves partnerships between
•   Lead agency for estuary management
                                                                       community, industry and government. However, community and
Estuaries lie between the terrestrial and marine spheres of natural    industry demands on estuarine resources often compete and
resource management. As a consequence their management has             sometimes conflict. Processes and institutional arrangements that
often been neglected. Overlapping responsibilities across tiers of     support community and industry involvement and action need to
                                                                       be built into all management activities.

                                                                                                                                                 FRONT COVER PHOTO: GIN ARM CREEK, QUEENSLAND. JEAN-PAUL FERRERO, AUSCAPE. PRINTING: NATIONAL CAPITAL PRINTING. JUNE 2000
Next steps in estuary assessment                                       Further information
The Australia-wide estuary condition assessment is now                 For further information contact:
concentrating on gathering information and providing
                                                                       •   National Land and Water Resources Audit
management recommendations for the more than 400 modified
estuaries around Australia’s coastline.                                          Phone:      02 6257 9516
The Australia-wide database being collated by all States and the
Northern Territory provides the framework for this assessment.
Results of the process-based classification of estuaries will be       •   CRC Coastal Zone, Estuary and Waterway Management
included in this database. Findings and recommendations will be                  Lynne Turner
complete by May 2001.
                                                                                 Phone:    07 3362 9377


                                            S T A T E    O F   T H E
                                            R E P O R T I N G
                                                                                                                       A U S T R A L I A N
                                                                                                                       GEOLOGICAL SURVEY
                                                                                                                       O R G A N I S A T I O N

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