Threatened Species and Communities
Key projects (with details below)
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Management of Tahbilk Lagoon to Benefit Freshwater Catfish
Tahbilk Lagoon near Nagambie, central Victoria, is well known for its biodiversity. It provides habitat for State threatened species including the Murray-Darling Rainbowfish Melanotaenia fluviatilis (Data Deficient), Watershield Brasenia schreberi (Vulnerable), Broad-shelled turtle Chelodina expansa (Endangered), Murray Short-necked Turtle Emydura macquarii (Data Deficient) and three threatened Ecological Vegetation Classes. In particular, Tahbilk Lagoon provides an important refuge for Freshwater Catfish Tandanus tandanus (Endangered), and is one of the few locations in Victoria where a relatively abundant population is known to occur. This species shows the interesting breeding behaviour of building circular nests in shallow areas, commonly made of stones. The male maintains the nest, fanning away sediment and chasing away predators. Research at the lagoon has revealed much information about Freshwater Catfish, particularly regarding movements and habitat needs. Radiotracking found that fish occupied small ranges, were usually close to the river bank, and showed associations with aquatic vegetation and woody structure. The Goulburn-Broken Catchment Management Authority (GBCMA) has since placed 135 snags (large woody habitat) within the lagoon to enhance habitat. While most Freshwater Catfish are not believed to undertake large scale migratory movements, movement between areas such as the Tahbilk Lagoon and the Goulburn River is still important. Analysis by NSW DPI Fisheries detected restricted genetic variation, highlighting the need to improve fish passage between these areas. The GBCMA and Tahbilk Winery are addressing this, through the installation of new culverts at road crossings. ARI will be fitting fish with microchip ‘PIT’ tags to gain a better understanding of how fish move in and out of the lagoon. Interpretive signs will also be designed and installed. The Tahbilk Lagoon area provides a great example of long term, integrated research and management, supported by many organisations and individuals. These include the GBCMA, Tahbilk Winery, DSE (ARI and North East Region), Goulburn-Murray Water, Dookie Seedbank, a riparian Landcare group, local landholders and interest groups. In recent years there has been extensive revegetation, fencing, riparian and aquatic weed management, water quality monitoring, establishment of bird hides, and fish and frog surveys. The GBCMA has funded much of the rehabilitation works. The Murray-Darling Basin Authority has also produced a Carp Management Plan for the Lagoon. For more information contact: pam.clunie@dse.vic.gov.au Bringing Native Fish Back - Freshwater Catfish at Tahbilk Lagoon
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Management of the Wellington Mint-bush in Central Gippsland: new insights into fire and browsing
The perennial shrub Wellington Mint-bush (Prostanthera galbraithiae) is classified as Vulnerable nationally, and is known from only two areas in Victoria. Populations at one of those areas, Holey Plains State Park in central Gippsland, are thought to be threatened by some fire regimes and browsing by herbivores, such as Swamp Wallabies. Some populations have been fenced for protection against browsing; however additional information was required about the response of plants to fire. A recent study funded by DSE (Environment and Water group), investigated the relationships between fire intervals, seed production and population structure, to provide information for more effective management of populations. The Wellington Mint-bush depends on seed stored in the soil for regeneration after mature plants have been killed by fire. Previously it was suggested that the optimal fire interval for this species is 10 to 15 years, with a minimum of five years between fires. To learn more about how fire influences the population structure, sites with different fire histories (up to 45 years between fires) were assessed. The proportion of seedlings was highest in the first year after fire, as expected, with mature plants more abundant four years after fire. It was noticed that at sites that were browsed, plant growth was significantly reduced compared to unbrowsed (fenced) plants. In addition, browsed plants showed no evidence of seed production. This study has provided two new insights into the ecology of the Wellington Mint-bush, and the extent of browsing damage. Firstly, long-unburnt areas still support viable populations of the species, indicating that the optimal fire interval may be more flexible than is currently thought. Secondly, although fire might cue mass germination, some germination from the soil seed bank can occur in the absence of fire. However, given the high browsing pressure in the area, the rate of recruitment is unlikely to be sufficient to maintain populations. In light of this new information, the most important management recommendation for the species is to protect populations from browsing. Fire management strategies are then likely to be more effective. Further studies on the herbivores responsible for browsing on plants, particularly in response to fire, would allow the development of targeted management strategies for the survival of the Wellington Mint-bush. For more information contact: michele.kohout@dse.vic.gov.au |
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Smoky Mice Movement and the Impact of Strategic Fuelbreaks in North-east VictoriaA network of strategic fuelbreaks has been constructed around Melbourne’s forested water catchments for the purpose of reducing the risk of fire damage to the city’s water supply. Fuelbreaks are linear clearings with most of the understorey and some of the larger trees removed. They often incorporate vehicle tracks, but are wider. Their purpose is to provide safer access for firefighters for back-burning operations during wildfires. However, the presence of fuelbreaks has the potential to affect native animals. ARI is investigating the impact of fuelbreaks on the movements of the threatened Smoky Mouse (Pseudomys fumeus) to see whether any modifications are required to limit barrier effects.A recent study on Smoky Mice to confirm the persistence of the species at a number of historical sites, found animals along a strategic fuelbreak in forest near Jamieson, north-east Victoria. Further surveys found more animals immediately adjacent to both sides of the fuelbreak. This provided an ideal location to investigate the impact of a fuelbreak on habitat use and population functioning of this species. By monitoring the movements of individuals, we can determine whether this fuelbreak forms a physical barrier or whether animals willingly cross the break. There is a possibility that Smoky Mice may not readily cross large open areas with no overhead cover. This could reduce breeding opportunities, dispersal and consequently genetic diversity and the future persistence of this threatened small mammal. Catch, mark and release trapping has identified 20 individual Smoky Mice around the fuelbreak. Two of these individuals were caught on both sides, indicating that they have crossed at some stage. Work is continuing to find out whether other Smoky Mice do the same, and how often. Radio-tracking of animals is now underway to determine more precisely where this nocturnal species travels during the night and how it uses its habitat. Preliminary radio-tracking results suggest that crossings may be more frequent than the trapping data indicate. It is hoped that radio-tracking data will reveal where along the fuelbreak animals are crossing, and whether there are particular conditions that facilitate these movements. If so, efforts can be made to enhance the fuelbreak and make it easier for small native mammals to cross. For more information contact: peter.menkhorst@dse.vic.gov.au or phoebe.macak@dse.vic.gov.auPage Top |
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Ecology of the Ancient Greenling DamselflyThe Ancient Greenling Damselfly Hemiphlebia mirabilis is the only living representative of the family Hemiphlebiidae in the world, with its closest relatives being 250-300 million year old fossils. They have an aquatic larval stage lasting about a year, after which they develop into metallic green terrestrial adults reaching just 24 mm in length. The species is threatened at state and international levels and is only found in south east Australia with isolated populations occurring in freshwater swamps, wetlands, billabongs and lagoons across South Australia, Victoria and Tasmania. Populations in Tasmania are considered to be remnants of the mainland distribution which became separated when the Victorian-Tasmanian land bridge was flooded approximately 13,000 years ago. Habitat loss is considered the main cause of its current restricted distribution and continues to be the greatest threat to populations.There is limited knowledge about many aspects of the biology and ecology of the Ancient Greenling Damselfly. For example, what habitat components make a wetland ideal for the species and what are the threats to populations across Victoria? Research efforts are often hampered by its small size, cryptic nature and fragmented distribution. Increased knowledge about habitat requirements and habitat use would enable appropriate management of wetlands for its conservation. To fill some of the knowledge gaps around the Ancient Greenling Damselfly, ARI is undertaking research, funded by DSE, at Wilsons Promontory National Park, and in the Glenelg Hopkins and Goulburn River regions of Victoria. Research includes monitoring adult-stage populations, assessing habitat and water quality, investigating the composition of aquatic invertebrate communities, and identifying any threats to the survival of populations. A number of organisations and individuals are integral to the success of the project including Parks Victoria, the Yea Wetlands Committee and friends, independent entomologists and a range of people interested in threatened species and their conservation. The research data will inform DSE threatened species conservation policy and provide land managers with the information needed to protect the species from threats and conserve populations at its current locations. For more information contact: di.crowther@dse.vic.gov.au Further information about this species in south west Victoria is available via SWIFFT (South West Integrated Flora and Fauna Team) Page Top |
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Threatened Northern Victorian Grassland FaunaAcross south-eastern Australia, most landscapes, including grasslands, have changed profoundly since European settlement. This was mainly due to agricultural activities (clearing, livestock grazing and cultivation), which has led to major fragmentation of many once continuous grassy ecosystems, leaving scattered remnants within a matrix of crops and introduced pastures. All plains grasslands in south-eastern Australia are now considered threatened. In Victoria, these have been assigned the bioregional conservation status of ‘Endangered’. Grasslands in northern Victoria are home to a suite of threatened fauna, most notably Plains-wanderer Pedionomus torquatus (Critically Endangered), Hooded Scaly-foot Pygopus schraderi (Critically Endangered), Common Dunnart Sminthopsis murina (Vulnerable) and Fat-tailed Dunnart S. crassicaudata (Near Threatened).Protected vegetation in this region comprises a network of sometimes interconnected reserves. These protected areas have recently expanded but there is limited biodiversity information for many of the extensive arid-adapted grasslands that are included in them. These grasslands are potentially important for a diverse suite of grasslands flora and fauna as well as providing a greater level of habitat continuity across the region. ARI and regional DSE staff recently surveyed native grasslands near Korrak Korrak and Bael Bael on the Avoca Plains, to assess the population status of the Hooded Scaly-foot. This legless lizard was found at both localities, along with a variety of other vertebrate species, several of which are threatened in a national or state context. A monitoring program for the Hooded Scaly-foot on three key north-central Victorian Reserves, including Terrick Terrick National Park, has been developed and surveys as part of this program will commence in summer 2010-11. This is one of several biodiversity studies currently underway in this part of Victoria. The contribution of the Northern Plains Grasslands Technical Advisory Group in facilitating or guiding this program has been invaluable. This group comprises scientists and representatives of Victorian land management agencies, including ARI. For more information: contact geoff.brown@dse.vic.gov.au Page Top |
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Vegetation Monitoring of Little Tern and Fairy Tern Breeding Sites at Lake TyersIn Victoria, Little Terns Sternula albifrons and Fairy Terns Sternula nereis breed at a small number of locations along the coast, including on islands in estuaries, and on ocean beaches. Threats to these species include predation by dogs and foxes, disturbance by humans and habitat loss. Action Statements for these species, currently under review, outline management designed to improve condition and extent of habitat, and research to increase current knowledge on aspects of their ecology. Two islands within Lake Tyers Estuary in East Gippsland are the subject of an ARI study to understand more about tern breeding sites. Raven Island and Plate Island are currently of critical importance for terns breeding in south east Australia because there are so few preferred nesting sites available. While there has been a decline in the use of breeding sites in other parts of East Gippsland, the number of terns using these islands has increased. About 25 pairs were recorded using the islands during the 2009/2010 breeding season. However, the on-going drought in the region and the artificial opening of the estuary entrance has meant that water levels in the estuary have generally decreased over the last five years. This has resulted in changes to the island’s landscape and increased the potential risk from predators. Only a small section of the islands are used for nesting, which may be related to vegetation characteristics as there is considerable variation in plant species, height and density across the area. Data is being collected on various aspects of the vegetation, and the relationship between vegetation and choice of breeding site is being examined. The aim is to define whether vegetation and environmental factors determine suitable nesting sites, and to establish a vegetation monitoring program. This information will help inform management of the nesting areas and improve the chances of terns successfully breeding on the islands. For more information contact: michele.kohout@dse.vic.gov.au Page Top |
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Victorian Threatened Orchid Recovery ProgramThe implementation of Recovery Plans for more than 60 nationally threatened orchid species is well underway across Victoria. A huge range of activities are involved, and ARI staff are providing expert scientific knowledge and advice to assist recovery programs of many species. Program activities include conducting demographic censuses of orchid populations, devising and implementing measures to protect orchid populations, establishing experimental methodologies to measure the impacts of particular threats or the effectiveness of management actions, and analysing datasets to optimise management regimes. The achievements of the Victorian Threatened Orchid Recovery Program have seen it recognised as leading orchid conservation in south-eastern Australia. In 2006 this program was the proud winner of the Banksia Environmental Foundation Banksia Award in the Land and Biodiversity category.Orchid monitoring protocols have been developed in response to the increase in monitoring conducted by regional DSE and Parks Victoria staff, and community volunteers. These protocols include a range of techniques that allow particular questions to be addressed at a population level, while detailing methods for analysing monitoring data for a species at a statewide level. It is critical that all monitoring programs are efficient, targeted, coordinated and scientifically robust, so that data analysis and management decisions can be confidently made at a regional, population, and species level. The results of a long-term monitoring program of Eastern Spider Orchid (Caladenia orientalis) populations found that fruiting plants were significantly smaller in the following flowering season, suggesting that there may be costs associated with reproductive effort, and that the common management practice of hand-pollinating plants to boost seed production may have a detrimental effect on individual plants. It is recommended that only a portion of plants are hand-pollinated each year. The study also showed that fire is an important element in the life cycle of this species. In the years immediately following a fire, the orchids are stimulated to flower. However, the heathland vegetation in which it occurs rapidly grows back after fire, causing a reduction in the flowering frequency of the orchids, A fire frequency of 8-12 years is recommended for the maintenance of this species. For more information contact: michael.duncan@dse.vic.gov.au Results of a long-term study on the Eastern Spider Orchid and another threatened orchid the Gaping Leek-orchid are now available: Coates, F. and Duncan, M. (2009) Demographic variation between populations of Caladenia orientalis - a fire-managed threatened orchid. Australian Journal of Botany 57: 326-339 Coates, F., Lunt, I. D, Tremblay, R. L. (2006) Effects of disturbance on population dynamics of the threatened orchid Prasophyllum correctum D.L. Jones and implications for grassland management in south-eastern Australia. Biological Conservation 129(1): 59-69 Page Top |
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Dams to Habitat: Providing Habitat for the Growling Grass FrogThe Growling Grass Frog (Litoria raniformis) is recognized as a threatened species at the state, national and international level. It was once widespread in Victoria but populations have declined. This is most likely because of degraded habitat and the fungal disease chytridiomycosis. To help address this decline, a project is under way to increase the availability of suitable habitat in rural areas by enhancing existing farm dams. This frog is one of a number of frog species that can live in farm dams. It is hoped to encourage more frogs to use dams by adding vegetation to them and providing structural habitat on the banks.To select dams which are suitable for enhancing, frog and tadpole surveys have been conducted at wetlands, streams and dams near known Growling Grass Frog populations using spotlights and call recognition. The habitat at a number of unoccupied dams will be enhanced and monitored over the next several years to see if the species has spread to live and breed in these modified dams. Dams will be enhanced by planting emergent and submerged/floating aquatic plants and adding refuge habitat to the banks. Fences will be erected to keep livestock away from the newly vegetated areas. Dams and adjacent waterways have been surveyed in western and central Victoria in the Corangamite, Glenelg Hopkins, Wimmera and North Central regions. Dam enhancement will first commence in the Corangamite and Glenelg Hopkins areas. Further surveys are being conducted in the Goulburn Broken Catchment Management Authority region to locate additional frog populations and dams for enhancement. Landowners kindly provided access to their properties and have been very supportive of the project. For more information contact: david.bryant@dse.vic.gov.au The following fact sheets are available: Growling Grass Frog dams to habitat fact sheet November 2009 
[PDF File - 900.0 KB]Growling Grass Frog dams to habitat fact sheet October 2008
[PDF File - 264.1 KB]Page Top |
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Research in Coastal Moonah WoodlandThe threatened plant community Coastal Moonah Woodland (Flora & Fauna Guarantee Act 1988) belongs to the Ecological Vegetation Class Coastal Alkaline Scrub (EVC 858). It occurs on the swales, lower slopes and upper south-facing slopes of coastal dune systems that are alkaline and usually derived from calcarenite. Coastal Moonah Woodland varies structurally and may occur as low forest or shrubland. Classic, mature examples of the plant community are dominated by Moonah (Melaleuca lanceolata subsp. lanceolata) trees that are often twisted by the wind into fascinating shapes. However, in addition to Moonah, Coast Tea-tree (Leptospermum laevigatum) and Coast Beard-heath (Leucopogon parviflorus), or some combination of these can also form the canopy. Several threatened understorey plant species are often supported in high quality remnants. |
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Threatened Alpine HerpetofaunaThere is currently one frog and six lizard species restricted to the Victorian alpine bioregion that are considered threatened at a national and/or state level. Grazing pressure (cows and feral horses), development of ski resort infrastructure, disease, and climate change are considered potentially detrimental to existing populations. To effectively conserve these species, thorough knowledge of their distribution and ecology is required. Collection of this information has included broad-scale surveys, development of monitoring protocols and taxon-specific surveys.With a particular focus on the Alpine She-oak Skink Cyclodomorphus praealtus, the use of artificial cover objects (roof tiles) as a survey and monitoring technique is being evaluated. This involves determining the suitability of this technique as a long-term monitoring tool of known populations, its ability to detect new populations, and whether it is a viable technique for investigating the impact of threatening processes on select populations. The surveys determine detection probabilities and site occupancy for this species. More than 50 sites have been established on the Omeo Plains, Bogong High Plains, the Mt Hotham area and on Mt Buller. Alpine She-oak Skinks have been detected on the Omeo Plains, Bogong High Plains, and in the Mt Hotham area, and two other threatened reptiles; Guthega Skink Egernia guthega and Alpine Bog Skink Pseudemoia cryodroma have also been detected beneath tiles. Problems with weather-related damage to tiles has lead to a current trial using tiles made from different material. The use of tiles as a survey technique is considered an effective way to gather information useful for conservation management. A number of survey sites were burnt during the 2006-2007 bushfires and will be the subject of fire-related research. For more information contact: nick.clemann@dse.vic.gov.au Page Top |
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