Australia's biodiversity

Newsletter on biological diversity conservation actions

Biolinks No. 6
Biodiversity Section
Department of Environment, Sport and Territories - January 1994
ISSN 1037 4434

Convention comes into force

The Convention on Biological Diversity came into force in Australia and elsewhere on 29 December 1993, ninety days after the 30th country ratified it. Nearly 170 countries have signed the Convention and 42 including Australia have already taken the next step of ratifying it.

The Conference of the Parties to the Convention, or COP, is the decision and policy making body established under the Convention. The first meeting of the COP will be held in November/December 1994.

In the interim period, the United Nations Environment Program (UNEP) is coordinating meetings of the Intergovernmental Committee on the Convention on Biological Diversity (ICCBD). Although the ICCBD does not have decision-making power, it is undertaking preparatory work on issues which will need to be considered by the COP.

A three day Global Biodiversity Forum held on 7-9 October 1993 was organised by the African Centre for Technology Studies, the World Conservation Union (IUCN), and the World Resources Institute, and was hosted by the IUCN in Gland, Switzerland. It was attended by 150 individuals from a broad range of interests and backgrounds, including governments, corporations, scientists, and conservation and development NGOs from 50 countries. The Forum discussed a wide range of issues about which participants held a range of perspectives. The aim was to analyse and foster dialogue among the various groups involved.

This was followed by the first meeting of the ICCBD held in Geneva on 11-15 October 1993. The meeting considered a range of issues, centred mainly on national biodiversity activities, various aspects of the Convention's financial mechanism, and technology transfer. The meeting also agreed to convene an intergovernmental meeting of scientific and technical experts to be held in March 1994. This meeting will provide a forum for: scientific cooperation for early implementation of the Convention provisions; the preparation of a scientific research agenda; and identification of innovative technologies and approaches to the conservation and sustainable use of biodiversity.

It is proposed that the next meeting of the ICCBD be held in May 1994.

Paper on Biodiversity and its value

The Biodiversity Unit, DEST, has produced an illustrated paper entitled 'Biodiversity and its value'. The paper outlines what biodiversity is, and the three levels at which it is usually defined: genetic, species and ecosystem. The paper also explains why biodiversity is important. The range of ecosystem services provided by biodiversity are described, as are the values of biological resources such as wood products, food and genetic reservoirs. The range of social and cultural values of biodiversity, including education, research, and aesthetic values are then outlined. To conclude, the paper describes the value of diversity itself.

If you are interested in obtaining a copy of this paper, free of charge, please contact the Biodiversity Unit. The address and phone number are on the back page.

National Strategy update

Development of the National Strategy for the Conservation of Australia's Biological Diversity is in its final stages. In finalising the draft National Strategy, the ANZECC Task Force on Biological Diversity took into account comments from relevant Commonwealth, State and Territory Government agencies, relevant Ministerial Councils, major business and industry bodies, peak conservation groups and the peak local government body. The Task Force has provided the final draft National Strategy to ANZECC for its consideration.

ANZECC agreed at its meeting of 15 October 1993 that the ANZECC Chair would send the National Strategy finalised by the Task Force to each State and Territory member requesting that they obtain whole-of-government clearance within their own jurisdiction by a specified date, with a view to the ANZECC-endorsed National Strategy being available for consideration by Heads of Government in December 1993. It was recognised that it would be desirable to have the National Strategy in place when the Convention on Biological Diversity comes into force on 29 December 1993 or very soon thereafter.

In line with this timetable the Commonwealth Government, on 16 December 1993, approved the draft National Strategy for the Conservation of Australia's Biological Diversity. After approval by the States and Territories the Strategy will be submitted to Heads of Government for adoption.

Norway/UNEP Expert Conference on biodiversity

The Expert Conference was hosted by the Norwegian Ministry of Environment in collaboration with the United Nations Environment Programme (UNEP). It was held in Trondheim, Norway, from 24-28 May, 1993, as a follow-up to the signing of the Convention on Biological Diversity and as preparation for its ratification and implementation.

The Norway/UNEP Expert Conference was essentially a discussion between scientists, resource managers, bureaucrats and policy-makers from approximately 80 countries, and the proceedings formed part of the basis for UNEP's preparations for the first Inter-governmental Committee (IGC) meeting of the Convention's signatories, held in Geneva in October 1993. The objectives of the Conference were to:

Themes discussed at the Norway/UNEP Expert Conference on Biodiversity included:

Discussions during the first days of the conference revealed considerable differences of opinion between the scientific community and the community of politicians and decision-makers. Several members of the scientific community expressed impatience with politicians and decision-makers, maintaining that the available knowledge about biodiversity loss is sufficient to justify much more decisive political action.

Politicians, on the other hand, felt that the considerable political challenges and the substantial efforts on their part to promote conservation and sustainable use of biodiversity in a political environment of diverging interests, were not duly appreciated.

During the formal and informal discussions at the conference, these differences were greatly reduced, and a much improved understanding and feeling of working towards a common goal were achieved.

Other issues

The issue of conservation and sustainable use of biodiversity must be kept high on the agenda of scientists and politicians alike.

The good oil

Despite eucalypts being quintessentially Australian, most eucalyptus oil produced to supply markets for medicinal, industrial and perfumery purposes is produced overseas.

The WA Department of Conservation and Land Management is seeking to tap into a potential new market for the oil as a replacement for some petroleum based industrial solvents (such as trichloroethane) which are to be withdrawn from sale under measures to combat ozone depletion. Eucalyptus oil is recognised as an excellent solvent with the added bonus of being of low toxicity and biodegradable. International consumption of the solvent trichloroethane is estimated to be one million tonnes, about 300 times the current world production of eucalyptus oil.

The program aims to develop mallee eucalypt varieties with improved oil yields which will then be provided to farmers as a new crop which will not only produce a profit, but provide shelter for stock, help rehabilitate the land and prevent further degradation such as salinization.

Landscope, Winter 1993

Biological diversity on agricultural land

Historically, the development of many areas of Australia for agriculture has meant the removal of the original vegetation and its replacement with crops and pastures. Much of the remaining native vegetation consists of small remnant fragments within a predominantly agricultural landscape.

Fragmentation leads to large scale changes in basic ecosystem processes, loss of habitat, the isolation of remaining populations due to lack of connectivity between fragments, and species decline. In many areas, large scale clearing has also led to a subsequent loss of agricultural production due to increasing soil salinisation, waterlogging and wind and water erosion.

Although the loss of agricultural production and conservation values are interrelated, the two problems have generally been addressed separately. Management of such landscapes has been fragmented, with the different land uses being managed in isolation despite the fact that they are all part of an interconnected whole. Agricultural land is historically managed without reference to areas of remnant vegetation either on the farm itself, or on adjoining nature reserves. Nature reserves are usually managed in isolation of the surrounding agricultural land, (both that used for production, and any remnant vegetation on farms).

One example is the wheatbelt of Western Australia in which there has been rapid and extensive clearance over the past century, with a large proportion of the region only being cleared in the last 50 years. The land is now degrading rapidly, and agricultural potential and nature conservation values are suffering. It has been estimated that salinity alone has caused a loss of 62.5 km² of land a year between 1955 and 1984, with the potential for an additional 2.5 million ha to be affected by salt unless action is taken.

Up to 94% of the native vegetation has been removed in some areas. The remnants provide the only indication of the natural ecosystems and processes which previously occurred. Vegetation communities on the more fertile soils have suffered more than others. The small size of the remnants, fragmentation and lack of connectivity between remnants, together with the arrival of introduced foxes, has led to the extinction of much of the mammal fauna, with some evidence that extinction of bird fauna may occur in the future. Overall, land degradation through unsustainable agricultural practices has led to a serious and continuing loss of both agricultural production and conservation value.

As with many other areas of Australia, action is being taken to try and halt this loss. Sustainable farming practices, tree planting to halt erosion and salinisation, and conservation of remnant vegetation are all being carried out. Most of this activity however is being carried out within traditional management boundaries. Difficulties arise when efforts are made to control salinisation on agricultural lands when the effect that remnant vegetation areas have upon hydrology is not taken into account. Equally, managers of remnant vegetation areas usually have little control over how adjoining land is managed. The small size of the remnants makes them vulnerable to the processes of degradation occurring in adjoining farmland. Changes to the hydrological balance, changes in soil nutrient status, edge effects due to altered exposure to climatic elements, weed invasion, and the impact of stock all ensure that the remnants will continue to degrade unless adjoining land management practices are adjusted.

Rather than management in isolation, an integrated approach to land management can be employed to maximise agricultural production on a sustainable basis and enhance the conservation value of the landscape.

Integrated management approaches are being developed in several places across the world. In Australia, the CSIRO Division of Wildlife and Ecology (with financial support from the Biodiversity Unit, DEST) is collaborating with the WA Department of Agriculture and local community groups in the central WA wheatbelt to develop principles and procedures for landowners, managers and community groups to use in constructing farm and catchment plans which integrate land and nature conservation objectives. It is intended that this exercise will produce techniques that can be applied in other augmented and managed landscapes.

In landscapes that have been radically altered, remedial action must first focus on arresting the ongoing degradation through the development of sustainable agricultural practices. If properly designed, solutions to agricultural problems can go some way towards alleviating the problems of habitat and species loss.

Revegetation activities are an important link between the two.Revegetation can help control degrading processes such as waterlogging, salinisation, wind and water erosion. If revegetation is designed only for a specific purpose, (such as controlling salinity), it may not have any significant benefit for other issues (such as maintaining conservation values). However, if in planning such revegetation, consideration was given to the location of any nearby patches of remnant vegetation, the siting of the areas for revegetation could then be designed to also provide for buffer zones between remnant areas and the surrounding agricultural land, or be shaped as corridors to link up remnant vegetation areas. The use of native and, in particular, locally native species, will also increase the conservation benefit.

This type of approach can be integrated with other farm planning practices such as matching management units (for example, fields) to units of soil types and taking drainage patterns into account. Property boundaries will however make it necessary for the integration to be tackled at a suitable regional or catchment scale to ensure that all relevant aspects of the landscape are taken into account. This does not mean that a strong 'top down' approach is required. Local community groups (such as Landcare groups) involving private land managers and cooperating with government agencies responsible for management of public land (such as local councils and State conservation agencies) can and do make use of expert advice to formulate their own regional level approach.

This approach aims to ensure that agricultural land is managed in a sustainable manner, including the conservation of biological diversity values, and will involve local people in the management of the conservation reserves in their area. This can be a valuable addition to the normally centralised, and usually under resourced, management of nature conservation reserves.

References

Hobbs, R.J. & Saunders, D.A (1991), 'Reintegrating fragmented landscapes, a preliminary framework for the Western Australian Wheatbelt', Journal of Environmental Management, 33, 161-7.

Hobbs, R.J., Saunders, D.A., Arnold, G.W., (1993), 'Integrated landscape ecology: a Western Australian perspective' , Biological Conservation, 64, 31-38.

Hobbs, R.J. & Saunders, D.A., (eds) (1993), 'Reintegrating Fragmented Landscapes. Towards Sustainable Production and Nature Conservation', Springer-Verlag, New York.

Hobbs, R.J. (1993),'Can revegetation assist the conservation of biodiversity in agricultural areas?', Pacific Conservation Biology, 1, 29-38.

Conference – report

Conserving Biodiversity, Threats and Solutions was the title of a conference organised by the New South Wales National Parks and Wildlife Service (NSW NPWS) and held at the University of Sydney from 29 June to 2 July 1993.The impetus for the conference was to bring together a range of people from diverse backgrounds to find solutions to problems that are depleting biodiversity and to assist the NSW NPWS develop a strategy to conserve biological diversity in NSW. Expert speakers from relevant fields covered a broad range of issues. The focus was on practical solutions at the State level, although there was some discussion of national and international concerns. Topics included habitat loss and degradation, pollution of water resources, the impacts of weeds and feral animals, the commercial use of native biota, changes to fire regimes, climate change, and the role of governments in solving problems. A special feature of the conference was evening forum sessions open to the public. Topics addressed were: 'Conservation of biodiversity is the most important aspect of ecologically sustainable development', and 'The role of reserves in the conservation of biodiversity'. The topics were debated by relevant experts and then opened to audience participation. A wide selection of posters were displayed, ranging from specialist research projects to practical solutions to the conservation of biological diversity. The conference illustrated the breadth of the problems facing us in our efforts to conserve biological diversity. In the concluding sessions, speakers emphasised the need for the following:

The Conference was sponsored by DEST. Further information may be obtained from Dr Ross Bradstock, NSW National Parks and Wildlife Service, telephone: (02) 585 6492.

Workshop on rapid biodiversity assessment

On 3-4 May 1993, the Research Unit for Biodiversity and Bioresources, Macquarie University, ran a useful and successful workshop on rapid biodiversity assessment (RBA).

The workshop was sponsored by the Biodiversity Unit, DEST, the NSW Forestry Commission, the NSW Environment Protection Authority, and the NSW National Parks and Wildlife Service.The major goals of the workshop were:

One of the reasons for the success of the workshop was that it brought together those researching RBA in the scientific community, the current users of some of the techniques, and a range of potential users of RBA, including Government and industry representatives, who identified their information needs.

The workshop was structured in three sections: research in rapid biodiversity assessment; applications and needs; and future uses and research.

There was widespread support for the development of rapid approaches to biodiversity assessment from the workshop participants. It was recognised that in many instances the taxonomy of organisms was unknown, that taxonomists were close to 'extinction', that identification can be time consuming, that costs can be high, and that for many applications new, quick and relatively low-cost methods must be found.

Numerous potential applications for RBA were identified by workshop participants, including:

1. surveys

2. conservation assessment

3. impact assessment and threat control

4. monitoring

5. rehabilitation

The transferability of RBA information was an issue of interest to Government, as was the current and potential availability of infrastructure resources such as reference collections and facilities. How RBA could assist with general conservation questions such as rarity, threat assessment and its usefulness in conservation evaluation were other common questions. It was also noted that the current legislative framework for wildlife management and conservation is based on a taxonomic approach, for example threatened species protection, and controls over the export of native species. New methods developed would need to be consistent with the current conservation and management framework.

In addition to the need for research to answer these operational questions, a number of major scientific research directions were identified in the workshop, including: the identification of predictor sets and the testing of their usefulness for selected ecosystems; the validation of modelling approaches to biodiversity assessment; education and training of biodiversity technicians; and the establishment of agreed standards and protocols.

The proceedings from this workshop are now available.

Contact:

Robyn Delves, Research Unit for Biodiversity and Bioresources Macquarie University, Sydney, 2109 Telephone: (02) 805 8153.

Choosing an optimal reserve system

M D Young and B M Howard, CSIRO Division of Wildlife & Ecology

The CSIRO Division of Wildlife and Ecology, assisted by funding from DEST, is undertaking research which broadly aims to:

  1. identify the most cost-effective options available to enhance biological diversity conservation objectives; and
  2. demonstrate the social and economic implications of alternative conservation instruments, such as the use of reserves, land management controls or restricted property rights (easements), to enhance biological diversity conservation.

Building on a Statewide Resource Information and Accounting System (SRIAS), being developed by CSIRO and the NSW Land Information System, the project is designed to answer questions such as:

The project will examine these issues across the State of New South Wales and seeks to place biodiversity issues in a social and economic context.

Selecting new reserves

A number of methods for selecting new reserves are available. They are designed to include elements within a reserve system in a manner that makes efficient use of the total reserve area. Elements may describe any measure determined to be an indicator of biodiversity. These may include environmental domains, floristic communities, species distributions, or a combination of all three.

To provide for flexibility, three methods of selecting protected areas, based on at least two elements, will be examined.

The first method is a richest area first approach. Developed by Kirkpatrick (1983) it first chooses sites with the most elements ('hot spots') then adds sites with sequentially the greatest number of elements not already included within the set of chosen sites, and continues adding sites until all elements are represented.

The second method uses a minimum set algorithm (Margules et al, 1988). This method first chooses sites with unique elements (or the most restricted elements), then adds sites with sequentially more widespread elements.

The third selection method gives preference to those elements most at risk and leaves out those that are threatened by existing land-use practice.

Costing target levels

It is also proposed to evaluate costs associated with meeting a range of conservation target levels for the three methods of selecting protected areas. Target levels may be defined:

Once costs associated with each approach have been estimated and the 'target by selection method' trade-off matrices prepared, the project will examine the implications of implementing each option, under alternative budget constraints, and in situations where it may not be possible to represent a sample of all elements in a reserve system. When elements are not available for inclusion in reserves, the option to use easements over private land containing desired elements will be analysed.

Finally, the project will examine opportunities to target expenditure so that multiple objectives can be achieved. For example, it may be possible to target off-reserve habitat protection to reduce soil erosion or dryland salinity problems.

References

Kirkpatrick, J.B. (1983), 'An iterative method for establishing priorities for the selection of nature reserves; an example from Tasmania', Biological Conservation, 25, 127-134.

Margules, C.R., Nicholls, A. O. & Pressey, R.L., (1988), 'Selecting networks of reserves to maximise biological diversity', Biological Conservation, 43, 63 -76.

Sarre, A. (1993), 'Designing for reserve systems a scientific approach', Tropical Forest Management Update, 3(3), 4-6.

Cemeteries: a refuge for biodiversity

Cemeteries have a role to play in conserving Australia's biological diversity as they often provide refuge for endangered or rare plant species. Much Australian vegetation has been cleared or modified which has resulted in the populations of many species being reduced to small remnant patches.

Native species usually occur in small communities in parts of the cemetery not used frequently or along paths and on grave plots. Mowing of paths does not deter the plants which also survive in cracks in gravestones, spaces between graves, along grave surrounds and edges, on fenced-off graves, and near perimeter fences.

However, natural vegetation in cemeteries faces a number of threats. Caretakers can maintain the area with the view to keeping the cemetery neat and tidy, consequently destroying the natural vegetation and preventing any revegetation. Remote cemeteries, on the other hand, can be left to become overgrown usually with weeds overtaking the natural vegetation.

New South Wales

Sydney's Rookwood Cemetery, one of the largest cemeteries in the world, contains significant areas of remnant vegetation. The cemetery represents one of the only significant areas of remnant native bushland within a ten kilometre radius of the city and contains a population of the rare and endangered species, downey wattle, several species of notable terrestrial orchids and also supports populations of native fauna. A management plan has been prepared for Rookwood and currently some bush regeneration work is being undertaken in areas set aside for the long term conservation of the indigenous vegetation.

Other cemeteries in the Sydney region also contain substantial stands of native vegetation, some of it confined only to one site. The most prominent of these are the Liverpool General Cemetery, St. Mark's Anglican Church at Appin and the St. Thomas' Anglican Church at Narellan, where a rare example of the rice-flower Pimelea spicata is known to exist. This particular type of rice flower is an endangered species and is in serious risk of disappearing from the wild state within one or two decades if present land use continues.

Using funds from the Save the Bush program, operated through the Australian Nature Conservation Agency, the Conservation Council of the South-East region and Canberra recently administered a survey of cemeteries in the Southern Tablelands of New South Wales. The survey of 114 cemeteries highlighted their significance for conserving Australia's biodiversity.

Thirty cemeteries were found to contain plant and invertebrate species considered to be either rare, indicators of undisturbed habitat or had restricted or disjunct distributions. These included Bookham, Tallong, Captain's Flat, Major's Creek, Delegate and Round Plain cemeteries. Other significant findings include a new species of leek orchid, and three undescribed species of terrestrial orchid.

ACT

The Hall cemetery in the ACT is another example of a protected reserve with considerable conservation value. It provides a habitat for the wingless grasshopper (Keyacris scurra), a species known in only a few locations in the ACT and disjunct locations in NSW, and the only known population of the leek orchid Prasophyllum petilum. In 1986, as part of the cemetery's management plan, several seedlings of the endangered small purple pea (Swainsona recta) were established in the grounds.

Victoria

One of Victoria's few remaining, relatively undisturbed areas of bull oak (Allocasuarina luehmanii) woodland is in the tiny Upper Regions Cemetery near Dimboola. This area could hold the key to the future of the once dominant woodland species throughout the Wimmera Plains. Using the cemetery site, researchers are hoping to develop an overall picture of the bull oak woodland so that management advice can be formulated and passed on to landowners in the Wimmera, allowing them to regenerate their existing remnant bush blocks.

Tasmania

The perennial herb scaly buttons (lanky buttons) was once widespread in Tasmania, and now is only found in cemeteries at Jericho and Bothwell. The Hamilton Cemetery has the largest display of a small daisy called Podolepis jaceoides and one of the largest populations of the rare, small yellow flowered herb Velleia paradoxa.

The cemetery at Campbelltown had one of the only two known stands of a dwarf, tufted herb Colobanthus strictus in Australia, when stock was introduced and subsequently destroyed the population. There is some hope that if the area is protected again, the population might recover. This is a good example of the need to establish sound management practices for the conservation of native flora and maintenance of biological diversity.

South Australia

West Terrace Cemetery, situated near the centre of Adelaide, once harboured nearly 50 species of native plants. Today, the most important of these are: quandong (Santalum acuminatum), mallee box (Eucalyptus porosa), native apricot (Pittosporum phylliraeoides), umbrella wattle (Acacia ligulata), black-anther flax-lily (Dianella revoluta) and berry saltbush (Atriplex semibaccata).

Another outer metropolitan cemetery at Willaston has remnants of several rare or threatened plants for the Southern Lofty botanical region, such as yellow-flowered sour-bush (Choretrum chrysanthum), broom ballart (Exocarpos sparteus) and chinese scrub (Cassinia arcuata).

A local cemetery at Frances, in the south-east of South Australia, conserves a fine stand of bull oak open woodland, a plant association which is seldom conserved anywhere in South Australia. This cemetery was also the site of a recent discovery of a colony of 50 plants of the rare leafy templetonia, Templetonia stenophylla. There are only three other populations known.

Other cemeteries with significant areas of native vegetation are at Cambrai in the Murray Mallee, Ardrossan on Yorke Peninsula, Barabba near Balaklava, Penwortham in the beautiful Clare Valley, and at Macclesfield in the Central Mount Lofty Range.

Western Australia

A small cemetery at Gingin, Western Australia, has gained significance both nationally and internationally for its rare hybrid of the red and green kangaroo paw, Anigozanthos manglesii, and the common cats paw, A. humilis. Regular disturbance of the cemetery has altered its distinct ecological conditions providing an area where plant communities are actively changing composition and species are actively hybridising. A large number of tourists now visit the site.

Although there has been no systematic survey of cemeteries in Western Australia, it is believed that cemeteries in the wheatbelt region are of particular ecological importance because extensive clearing in the area has removed most of the original vegetation.

Management

In general, the careful use of fire is preferable to the blanket use of chemicals in the control of weeds in cemeteries. Hand weeding and careful stump poisoning can be used to eradicate woody weeds. Mowing should be confined to walkways and access areas, and where native plants make up grassy areas, mowing should be left until late spring to allow native plants to flower and set seed. Grave plots should be left as undisturbed as possible and plant species in the cemetery should be identified so that endangered plants can be left undisturbed, except for careful weeding. If expansion of the cemetery is needed, it is a good idea to transplant young native plants to an unused part of the cemetery, especially if rare plants are present.

Australia represents a vast resource of plant life, with some 85 per cent of the estimated 21,000-23,000 different species of native vascular plants not found anywhere else in the world. It should be noted that 77 of these species have become extinct in the last 200 years and another 930 species are endangered or vulnerable. Remnant vegetation, such as that found in many cemeteries, provides a habitat that can help the survival of many species of Australian plants and animals.

Acknowledgements

This article is based on information provided by Russell James, Australian Nature Conservation Agency; Darrell Kraehenbuehl, SA Department of Environment and Land Management; and Stephen Hopper, Kings Park and Botanic Garden, WA.

Mangrove biodiversity – its value to Australia

Barry Clough, Australian Institute of Marine Science

Mangrove forests are a feature of the intertidal zone along the tropical and subtropical coastlines of the world. The remaining area of mangroves worldwide is estimated to be about 20 million hectares. Australia, with about 1.2 million hectares, ranks second behind Indonesia (4.3 million hectares) and just ahead of Brazil (1 million hectares) in its area of mangroves. About 35 of the world total of 50 or so mangrove species are found in Australia.

Mangrove species do not belong to one specific taxonomic group. Most of Australia's mangrove species are in the form of salt tolerant shrubs and trees; however, there is also a mangrove palm, Nypa fruticans, and a mangrove fern, Acrostichum speciosum. Most mangrove species are widely distributed in north-eastern Australia, which is believed to have been near the epicentre of mangrove evolution.

Within Australia, the greatest number of species is found along the eastern coastline north of Cairns, where mangroves often form extensive mixed -species tidal forests that may rival terrestrial forests in luxuriance and productivity. Further south the number of species decreases progressively with increasing latitude, with only one species, Avicennia marina, being found at the southernmost limit of mangroves at Corner Inlet in Victoria. This reduction in species diversity with increasing latitude is generally attributed to temperature. The Western Australian coastline has significantly fewer species than the east coast at comparable latitudes, partly because it is more arid, and partly because of its large tidal range and greater exposure to storm and wave damage (the Great Barrier Reef provides some protection to mangrove areas from storms and waves along the eastern coast of Queensland).

Australia is fortunate that most of its mangroves are in northern Australia where they are remote from urban centres and relatively free from major human impacts. In consequence, and historically more by default than by any conscious policy to protect them, mangroves in Australia are still relatively pristine and have not been exposed to the widespread exploitation and destruction common in many other countries. Human impacts on mangroves have been largely confined to urban, industrial, port, airport and resort development.

Once regarded as wasteland, the ecological, environmental and economic value of mangroves to Australia is now widely acknowledged. Ecologically, they are important as a unique habitat for a wide range of microscopic and macroscopic invertebrate fauna, some of which are dependent entirely on mangroves. The invertebrate fauna play a key role in coastal food chains.

Mangroves also provide habitat for a large number of vertebrate species, the most notable of which is the saltwater crocodile in northern Australia. In addition, Australia has a remarkably rich mangrove-dependent avifauna by world standards. Of the 200 or so species of birds that have been recorded from Australian mangrove vegetation, 14 are virtually confined to it, another 12 are limited by it for at least part of their range, and a further 60 or so use it regularly throughout the year or in certain seasons. Many of these species use mangroves as nesting and roosting sites, and most use them as foraging sites. Geographically, the number and diversity of bird species increases with the number and structural diversity of mangrove tree species. Mangroves protect the coastline and maintain coastal water quality. They reduce coastal erosion and lessen the effects of storms and strong winds. Mangroves also trap silt and filter effluents that would otherwise have a harmful impact on marine organisms. Mangroves play a significant role in maintaining the biological diversity of both terrestrial and marine environments. Mangrove-lined estuaries are key nursery areas or feeding grounds for a number of commercially valuable fish and shrimp species at certain stages in their life cycle. Decomposing litter from mangrove plants is a primary source of food for many marine organisms. For example, the banana prawn, Penaeus merguiensis, appears to be strongly mangrove-dependent in its juvenile stage. Barramundi and mangrove jack both feed extensively on smaller mangrove-dependent fish species.

In favourable environments, mangrove trees grow to heights of more than 30 m and have trunks of up to 1 m in diameter. They are widely used in plantations throughout south-east Asia for production of timber, firewood and charcoal. After harvesting, the forest is usually replanted according to a specified management plan to ensure sustainability. Australia presently has no timber industry based on mangrove forests. However, there are a number of species that produce timber of a quality suitable for furniture and specialty timbers. Most of these species grow naturally in the more landward zone of mangrove forests where mechanised harvesting is potentially feasible. The Australian Institute of Marine Science in Townsville is presently carrying out research on some of these mangrove species that show particular promise for commercial timber production. Areas where they might be grown as plantations include low-lying coastal land presently subject to occasional inundation by the sea, and coastal agricultural areas that may experience seawater intrusion as a result of a future rise in sea level.

It is a common misconception that all mangrove species require regular tidal inundation. Not all species have an obligate requirement for seawater and many will in fact grow quite well in non-tidal areas where the water table is near the soil surface. This suggests that mangroves could be grown in agricultural areas that have become degraded through a rising water table and soil salinisation. The main problem here is their lack of tolerance to low temperature, which would probably restrict their use for land reclamation to northern Australia.

Several species of mangrove show promise as landscaping plants in saline areas such as, for example, airports or other coastal developments that have been constructed on reclaimed coastal lands. Species such as the white-flowered Lumnitzera racemosa, its red-flowered relative Lumnitzera littorea, and Osbornia octodonta form highly attractive bushes of up to three metres in height, grow on a wide range of soil types and do not require regular tidal inundation.

It has been estimated that perhaps 30% of irrigated land worldwide, and as much as 50% of irrigated land in semi-arid and arid regions, is affected by salinity. Excess salinity also affects non-irrigated land in many parts of Australia. A considerable effort is now being made worldwide to select salt tolerant ecotypes of crop and tree species, and to improve their salt tolerance through genetic engineering.

Mangroves are amongst the most salt tolerant of tree species, some being able to survive and grow, albeit slowly, at soil salinities three times that of seawater. The indigenous Australian mangrove species span some 14 families and 25 genera of flowering plants. Different species have differing degrees of tolerance to salinity, and to both high and low temperature extremes. Even within species, there is a considerable degree of variability in tolerance to temperature extremes, and perhaps also salinity. Mangroves are thus a potentially rich source of genetic material for developing more salt tolerant fruit and tree crop species using emerging genetic engineering technologies. However, little research has been carried out and little is known about the long-term effects of translocating these species.

The identification and extraction of biologically active compounds with medicinal value from mangroves is another area in which little work has been carried out. The adaptation of mangroves to their unique environmental conditions may involve the synthesis of a range of potentially important bioactive compounds that are not synthesised by other plant species. Several species have been used as traditional medicinal plants by indigenous populations in many parts of the world. In Papua New Guinea, for example, the young twigs of Lumnitzera racemosa are chewed by women as a contraceptive. The active ingredient, which has not been isolated, is reported to cause permanent sterilisation. Excoecaria agallocha, which belongs to the family Euphorbiaceae, produces a milky sap which has been reported to cause blindness. Mangroves are thus a potentially rich source of biologically active compounds that may have significant medicinal value.

In view of the rapidly diminishing extent of mangroves worldwide, there is an increasingly urgent need to develop policies for the sustainable management of mangrove forests and the conservation of their genetic resources. A number of UN agencies, and others such as the International Tropical Timber Organisation (ITTO), as well as organisations such as IUCN and the International Society for Mangrove Ecosystems (ISME), have initiated or are supporting projects on the sustainable use of mangrove forests and the conservation of their genetic resouces.

For further information

Clough, B.F. (ed.) (1982), Mangrove Ecosystems in Australia: Structure, Function and Management, Australian Institute of Marine Science & Australian National University Press, Canberra.

Hutchings, P. & Saenger, P. (1987), Ecology of Mangroves, Queensland University Press, St. Lucia.

Lear, R. & Turner, T. (1977), Mangroves of Australia, Queensland University Press, St. Lucia.

Robertson, A.I. & Alongi, D.M. (eds.) (1992) 'Tropical Mangrove Ecosystems', in Coastal and Estuarine Studies 41, American Geophysical Union, Washington, DC.

Tomlinson, P.B. (1986), The Botany of Mangroves, Cambridge University Press, Cambridge.

Whole farm planning

Biolinks No 5 featured an article on whole farm planning, a concept pioneered by the Potter Farmland Plan project. The experiences of the Potter Farmland Plan project are documented in a video series and accompanying manual ('On Borrowed Time') which is available from:

Victorian Conservation Trust
8th Floor, 49 Spring Street
Melbourne Vic 3000
Telephone: (03) 651 4040
Facsimile: (03) 651 4048.

Remote sensing and biodiversity: ideas and initiatives

Dean Graetz and Murray Wilson, CSIRO, Division of Wildlife & Ecology

In this article we argue that remotely sensed data is a very powerful but under-used tool and that a fresh look at the biodiversity issue is long overdue. We also describe a current collaborative project of CSIRO and DEST that puts our arguments and understanding to the test.

Both researchers and managers can talk about 'typical' habitat without any reference to spatial data sets to substantiate their claim. Many of the serious conservation debates, for example forest fauna and logging conflicts, are conducted more with hand waving than with spatial data sets (images) to quantify the critical questions of WHAT, WHERE and HOW MUCH.

Remotely sensed data contributes to the management of biodiversity by quantifying landscapes and habitats and their changes through time the serious stuff of monitoring.

The data we are focussed on here are collected by machines (sensors) orbiting the earth aboard spacecraft. The data consist of repeated, objective measurements of electromagnetic radiation received at the satellite which are relayed to earth and electronically archived. A wide range of electromagnetic wavebands are used: there is reflected light in the visible and near infrared, emitted thermal (heat) radiation, and reflected microwaves (radar). All of these wavelengths interact differently with the nature and spatial pattern of the vegetation and soils, the landcover, of the earth's surface.

By understanding this interaction, it is possible to process these data to infer or estimate landcover properties, such as structure (biomass, leaf area index) and function (photosynthesis, evapotranspiration) as well as the spatial patterning of these structural and functional properties. Satellite data is easily geocoded and thus integrated with any other spatially referenced (mapped) data, such as species distribution, soil boundaries, and so forth. Because these data are a census (100%) sample, objectively and repetitively collected and geocoded, they are uniquely capable of assessing habitats as well as detecting and interpreting change, that is monitoring.

Satellite data can make a major contribution to the management of biodiversity by quantifying habitat condition (assessment) and change (monitoring).

Our second proposition is that a fresh look at the biodiversity issue is long overdue. In particular the perspective of the biodiversity question has been distorted by a concentration on fauna rather than habitat, and it has been most effectively hijacked by the 'rare fauna' and taxonomic interests to the detriment of a wider, balanced view of ecological change at landscape level. We hold that both flora and fauna must be considered together, shaped by our understanding of the dependence of the latter on the former, and focussing on the cumulative changes in landcover or habitat.

To put our ideas to the test, we have entered into a collaborative project with the Biodiversity Unit of DEST that began in May 1993, for completion in December 1994. The goal is to use satellite data to conduct a baseline measurement of landcover condition as part of a first stage in a national assessment of biotic impoverishment, the loss of biodiversity.

The collaborative work is based on the following argument. Habitat and ecosystem are abstractions but central to modern ecological theory and management practice. Both can be made tangible at continental scale by equating them with landcover. For example, a particular assemblage of landcover types and their contained fauna can be equated to an ecosystem. Or, the type and condition of one particular landcover type can be equated to a habitat. It is recognised that this equivalence requires biological understanding that is currently mostly absent. Nonetheless, the reciprocal argument, that disturbed landcover represents change in ecosystem structure and function, for example habitat suitability, is universally accepted.

Biodiversity is likewise an abstract but invaluable concept. It can be made operational at continental scale by focussing on its change rather than the absolute by focussing on its loss, biotic impoverishment, rather than biodiversity itself. We can proceed by the qualitative argument that disturbed landcover (transformed, fragmented, invaded) will result in biotic impoverishment. The quantitative refinements of this model, such as how much disturbance results in how much loss of biodiversity, are currently lacking. These requirements are the focus of active research within CSIRO and elsewhere and much will be achieved within the next few years.

It is not necessary to wait for the development of these quantitative models, the 'how much' relationships. A substantial improvement in the national assessment of the extent and severity of biotic impoverishment can be achieved immediately by an improved continental mapping of contemporary landcover status combined with an integration and modelling of existing data sets.

The fundamental data set from which all others will be based is a contemporary, high resolution (1 km) map of landcover disturbance for the entire continent derived from satellite data. In this case data from a sensor system called AVHRR on board the NOAA series of space craft will be used.

From the landcover disturbance data set we will derive two indices of the severity of biotic impoverishment, both present (LOSS) and potential (VULNERABILITY). In addition, this project will demonstrate the relevance of this methodology to the national interests in both State of the Environment (SoE) Reporting and the requirements of a national biodiversity monitoring program.

The products of the completed project will be precision geocoded spatial data sets in a format suitable for lodgement with ERIN and NRIC, and for public distribution. We will also commit all the relevant data sets and explanatory notes to a CD-ROM, co-published by CSIRO and DEST, that is aimed at the high school, university and public educational market, and which can be widely distributed. Maps showing the extent of clearing and disturbance, will also be provided as paper products.

An outline of the CSIRO-DEST collaborative project is available from: Dean Graetz and Murray Wilson, CSIRO, Division of Wildlife & Ecology, PO Box 84, Lyneham, ACT, 2602. Facsimile: (06) 241 3343.

NOTE: The authors have published a book and a CDROM of satellite data which demonstrate how much, in what way and where the landcover of this continent has changed in the last 20 years. Looking Back: The Changing face of the Australian continent, 1972-1992 is available for $50, including postage, as is the CDROM, 'AUSWATCH' at $30, both from: COSSA, PO Box 3023, Canberra, ACT, 2601. Please make cheques payable to of Collector of monies, COSSA'.

Conservation through sustainable use of wildlife: a public forum

The Centre for Conservation Biology (University of Queensland) and ANZECC will host a public forum to debate the use of biological resources throughout Australia, New Zealand, the South Pacific and South-East Asia for conservation and sustainable development. The forum will be held during February 8-11, 1994.

The forum will examine the potential for diversifying the use of wildlife as a conservation tool; it will develop strategies for conservation through ecologically sustainable use of wildlife; and will provide guidance for national planning of the use of wild species for conservation and sustainable development.

Contact:

Dr Peter Hale
Centre for Conservation Biology
University of QueenslandBrisbane Qld 4072
Telephone: (07) 365 2527 Facsimile: (07) 365 1655.

Biodiversity conservation in the South Pacific

The South Pacific is characterised by small land masses dispersed over part of the world's largest ocean. There is a high degree of ecosystem and species diversity and, in some areas, high levels of endemicity (that is, species found nowhere else). There is also a high degree of economic and cultural dependence on the natural environment and vulnerability to a wide range of natural disaster. The diversity of cultures and languages, traditional practices and customs are central to the close and special relationship of Pacific peoples with their environments.

The combined Exclusive Economic Zones (EEZs) occupy 30 million square kilometres of the Pacific ocean, but the land area is only 1.8 per cent of that total. With an estimated population of only 5.8 million, the Pacific Islanders' capacity to protect their fragile environments against damage from both internal actions and external influences is constrained.

The tropical South Pacific region is renowned for its high levels of species diversity and endemism. Species diversity and endemism appear to be highest on the larger high islands of the western Pacific (New Caledonia, Papua New Guinea, Solomon Islands and Vanuatu), declining east from the continental masses, and south and north away from the equator. Except on the atolls, high levels of terrestrial endemism occur throughout the region due to the isolated evolution of island species.

For example, Papua New Guinea has about 100 species of mammals, 70 species of snakes, crocodiles, over 65 species of birds (including the rare birds-of-paradise and the cassowary which are of considerable nutritional and ceremonial importance), and a very rich insect fauna which includes some of the rarest and largest moths and butterflies, and the dreaded malaria vector, the Anopheles mosquito. It's flora is likewise very rich. In stark contrast, Kiribati and Tuvalu's native floras have few native species, and the only mammal is the Polynesian rat (Rattus exulans).

The region has the most extensive coral reef systems in the world, with vast and complex marine ecosystems. The estimated extent of biological diversity, however, is not conclusive for either marine or terrestrial systems because detailed biological inventories are lacking; only approximately ten per cent of tropical species have been described.

Other than the potentially catastrophic consequences related to sea level rise through climate change, the major threats to the biodiversity of Pacific Islands are associated with the following factors: high unemployment levels; lack of education; reliance on the global economy; inadequate infrastructure; pollution; very complex land tenure arrangements; unsustainable resource extraction; and introduction of pests. As is fairly self-evident, in most cases these issues are interrelated. The list also includes many problems Australians would be familiar with. Tackling these issues in the socio-political environment of the South Pacific however, requires original and tailor-made solutions.

Regional environment program

Over the last 15 years the 27 countries and territories of the South Pacific region have organised themselves to protect and improve their shared environment and to work cooperatively to improve the quality of life for both present and future generation. The South Pacific Regional Environment Programme (SPREP) has come to be recognised, regionally and globally, as the organisation responsible for environmental coordination, protection and management within the Pacific Island community.

Working through its member governments, SPREP has undertaken a far-reaching set of programs concerned with training, research, and resource management. The Australian Government is a major supporter of SPREP, and provides regular financial and technical assistance for its activities.

Biodiversity conservation program

The South Pacific Biodiversity Conservation Programme (SPBCP) is a five-year US$10 million project of the pilot phase of the Global Environment Facility administered by the United Nations Development Programme and being executed by SPREP. The Australian Government co-financed and helped to design the program, and will continue to be involved in its implementation. Briefly, the program intends to protect biodiversity within a number of Pacific Islands by facilitating the establishment of a series of large, diverse Conservation Area Projects (terrestrial, marine and combined) in which there are agreed criteria for development based on long-term ecological sustainability.

Emphasis in the program will be on assisting local partnerships to develop sustainable management structures for biodiversity. conservation. It will attempt to help local communities, non-government organisations, and government agencies establish viable management systems for biodiversity conservation and sustainable use. There will be a bias towards testing models which achieve concrete outputs and which are likely to be replicable in other areas within the region.

Nature conservation and protected areas

SPREP coordinated the Fifth South Pacific Conference on Nature Conservation and Protected Areas, which was held in Tonga from 4-8 October 1993. The conference had the topical theme of 'Community Involvement in Biodiversity Conservation'. Thirty papers were presented at the Conference which was attended by 120 participants, representing 17 countries, over 30 NGOs, and academic institutions. It passed 18 resolutions to guide government and non-government organisations in conservation activities through the region. Resolution 9 on the Convention on Biological Diversity urges member countries to sign and ratify the Convention and requests SPREP to assist with developing and implementing associated national legislation.

Sustainable development

The Rio Earth Summit of May 1992, (UNCED), is widely recognised as the most significant global environment event of the last two decades.

Recognising the ecological vulnerability of islands, national governments decided at the 47th Session of the United Nations General Assembly to convene the Conference on the Sustainable Development of Small Island Developing States in Barbados in April/May 1994. The two week session, effectively a 'mini UNCED' for small islands, will elaborate strategies and measures to enhance their ecologically sustainable development. Australia chaired a Preparatory Committee, or 'prepcom', of the Conference in Geneva in August 1993. The major product of the prepcom was the draft Program of Action for the Sustainable Development of Small Island States which will be the basis for discussion at the Conference. The Program will have a similar role to that which 'Agenda 21' had for UNCED. SPREP is coordinating the Asia-Pacific input to this Conference.

Ocean Rescue 2000

Ocean Rescue 2000 is a ten year initiative which aims to promote the conservation and sustainable use of the marine environments of Australia and its territories.The program is administered by DEST, the Great Barrier Reef Marine Park Authority and the Australian Nature Conservation Agency.The following activities are included in the program.

The State of the Marine Environment Report (SOMER) is a comprehensive description and assessment of our marine environment, resources and the impact of human activities. It will provide baseline information for other programs and for future environmental reporting.

The national representative system of marine protected areas will promote the expansion of marine parks and reserves and ensure that examples of the full range of Australia's marine environments are managed and protected, including fish habitats to safeguard marine fish stocks.

The national marine education program aims to provide accurate and timely information to the community, schools, media, industry and recreational groups.

The national marine information system, developed by the Environmental Research Information Network (ERIN), will provide a comprehensive computerised scientific information base including data on fisheries, mineral resources, ocean currents, distribution of marine life and climate.

The marine and coastal community network (M&CCN) will foster community involvement in marine conservation through facilitating information exchange and consultation

Contact:

John Gillies,
DEST,
GPO Box 787
CANBERRA ACT 2601
Tel: (06) 274 1432 Fax: (06) 274 1927.

The Ocean Rescue 2000 UPDATE
 from: David Lloyd,
PO Box 1379, Townsville Qld 4810

M&CCN Newsheet
from: Di Tarte
PO Box 49
Moorook QLD 4105

The Food Gatherers

We are the food gatherers, we
And all the busy lives we see,
Fur and feathers, the large and small,
With Nature's plenty for us all:
The hawk circling over the plains,
The dingo, scourge of his domains,
The lone owl whose voice forlorn
Pursues the sunset into dawn.
Even the small bronze chickowee
That gossips in bright melody
Look, into the clump he's gone,
He has a little murder on !
For food is life and life is still
The old carnage, and all must kill
Others, though why wise Nature planned
Red rapine, who can understand?
Only for food, never for sport,
That new evil the white man brought.
Lovely to see them day by day,
The food gatherers, busy and gay,
But most of all we love our own,
When as the dulled red sun goes down
Fishers and hunters home return
To where the family fires burn.
Food now and merriment,
Bellies full and all content
Around the fires at wide nightfall,
his the happiest time of all.
– Oodgeroo of the tribe Noonuccal (formerly Kath Walker)

From My People, 3rd Edition, 1990 Jacaranda Wiley Ltd.

Biodiversity Unit, DEST
GPO Box 787 Canberra ACT 2601
AustraliaTelephone (008)-803 772

Biolinks is published by the Department of the Environment, Sport, and Territories. The views expressed are those of the individual authors and do not necessarily reflect those of the Commonwealth Government or the Department.

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