Conservation and Environment

Mapping and Measuring Biodiversity

The development of innovate ways to assess biodiversity and habitat condition allows us to build a greater understanding of the complex interactions between individual species and the environment in which they live. Utilising these methods provides us with the ability to undertake inventory and assessment, which is essential for the establishment of baseline biological data that will aid in the successful management of our environment.

Key projects (with details below)

Annual Summer Waterfowl Count Index of Wetland Condition Mapping Vegetation Extent and Condition Across Victoria Waterbird Numbers at the Western Treatment Plant Development of a Method for Monitoring Deer in Forests Surf Coast Shire Flora and Fauna Biodiversity Movement Patterns of River Blackfish Heat and Motion-Triggered Cameras as a Survey Tool

Key projects (in other themes)

Identifying Sources of Carp in the mid-Murray River Using Otoliths (Invasive Species) Tracking Wild Dogs Using GPS (Invasive Species)

Annual Summer Waterfowl Count The Summer Waterfowl Count is a large-scale, co-ordinated survey of wetlands across Victoria to provide information on game duck distribution and abundance, waterbird breeding and large concentrations of protected species. The collected data are used to consider management options for the year’s duck hunting season. It has been conducted since 1987, when the (then) Department of Conservation, Forests and Lands initiated the procedure during a review of the management of duck hunting within the state. Counts take place each year over a nine day period in late February-early March by DSE and volunteers from Field and Game Australia, Birds Australia and the Bird Observers Club of Australia. The number of wetlands counted varies each year due to resources available and the number of wetlands known to be dry. All count data obtained during these surveys are sent to ARI where they are collated and stored within the DSE Victorian Wetlands database. Survey information is used to: identify wetlands holding large numbers of Freckled Duck Stictonetta naevosa, provide details on the distribution and numbers of protected and game waterfowl species, monitor sites where counts have been made since 1987 and thus provide information about general population changes over the years, provide information on local breeding of waterbirds, particularly colonial species. In 2008, around 58,600 game ducks and 41,500 non-game waterfowl (swans, coot, grebes and protected ducks) were counted from 191 wetlands. These are the lowest numbers of waterfowl per wetland recorded since the counts began, and follows a decline in waterfowl over recent years. Drought conditions are thought to have had an impact on waterfowl numbers due to fewer wetlands containing enough water to sustain bird populations. During the 2008 count, 54% of wetlands surveyed were dry. Species with ranges that extend to inland and northern Australia may have taken advantage of summer rains in these areas to breed in recently filled wetlands in other states instead of coming to Victoria. The low numbers of waterfowl has led to the cancellation of the duck hunting season over the past two years to reduce the pressure on populations and allow them to recover when conditions improve. For further information contact Daniel.Purdey@dse.vic.gov.au Page Top

Index of Wetland Condition It is widely recognised that natural resource management agencies require a relatively simple and rapid tool to assess the condition of their wetlands; however there is presently no standard method for doing this in Victoria. To address this, work over the past several years has lead to the development of the Index of Wetland Condition. The process has involved consultation with natural resource managers and wetland experts from Victoria and other Australian states. Currently the Index exists as a provisional method that requires systematic use and testing. It is composed of six categories based on the characteristics that define wetlands: soils, wetland catchment, physical form, water properties, hydrology and biota. The method aims to be easy to use and interpret, able to be applied at any time of the year, able to assess a wetland from a single visit and to differentiate natural from human-induced changes in condition. It applies to naturally occurring, non-flowing wetlands, which do not have a marine hydrological influence. The next stage of the Index development and implementation is underway. It aims to: coordinate assessments across the state using the Index; provide training to end users; systematically test the ability of the method to measure condition consistently across a condition gradient; and test other aspects of the method, for example the scoring system. Additional tools that will enhance the Index are also at various stages of development. One of these tools creates wetland base maps and is available on the DSE mapping page. For further information contact Phil.Papas@dse.vic.gov.au The following reports detail the development and design of the Index: IWC Conceptual Framework and Selection of Measures 2005 (PDF - 908 Kb) IWC Assessment of Wetland Vegetation 2006 (PDF - 1.3 Mb) IWC Review of wetland assessment methods 2007 (PDF - 476 Kb) Page Top
Mapping Vegetation Extent and Condition Across Victoria The management of native vegetation is undertaken by various government and non-government agencies at the regional, state and federal level. Such agencies use information about the level of depletion and, more recently, the ‘condition’ or ‘quality’ of native vegetation. There are now requirements to monitor changes in the coverage and condition of vegetation as the Victorian Government currently has a policy of ‘net gain’ in both the extent and quality of native vegetation across the State. ARI staff have been developing a range of novel datasets to assist land managers to make informed decisions about the management of native vegetation and conservation programs. Existing datasets included a series of maps that detail the types of vegetation across the State. While these are integral to managing native vegetation resources, they did not capture well the extent of non-woody or grassy types of native vegetation. Using remote-sensed imagery, GIS data and custom-developed software a more consistent appraisal of the extent of both woody and grassy vegetation types have been produced, as well as an assessment of the rates of loss and gain in these vegetation forms over a 10 year period. Additionally, similar technology has been used to produce a first-ever model / map of native vegetation condition across Victoria. Using approximately 17,000 ‘Habitat Hectare’ assessments, along with satellite and other data, the resultant maps display ecological condition covering most of south-eastern Australia. The maps will also provide a baseline for the continued monitoring of native vegetation into the future, as well as a more rigorous basis for making natural resource management decisions. For further information contact Graeme.Newell@dse.vic.gov.au Native vegetation spatial data can be accessed in various ways via the DSE website. The following article is available: Newell, G., White, M., Griffioen, P. and Conroy, M. (2006) Vegetation condition mapping at a landscape-scale across Victoria. Ecological Management and Restoration 7: S65-S68 Page Top
Waterbird Numbers at the Western Treatment Plant The Western Treatment Plant (WTP) at Werribee, managed by Melbourne Water, is used to treat over half of Melbourne’s sewage. The area comprises a series of lagoons and filtration paddocks that are used by waterbirds and is especially important during droughts when many wetlands in inland southern Australia are dry. A monitoring program has run for several years focusing on waterfowl, shorebirds (including migratory shorebirds that nest in Arctic Asia), ibis, terns and cormorants. Sewage treatment processes are currently being upgraded, which may alter physical parameters such as water quality. Waterfowl densities on the lagoon system, paddocks and shoreline are regularly recorded to track changes. These changes are then related to natural events and weather patterns, and to changes in water quality and nutrient levels on selected ponds. Data have been modelled to predict effects of different management scenarios, including possible changes to salinity. Waterfowl numbers are counted every two months and have exceeded 100,000 on many occasions. Over the six counting periods of the 2006-2007 year a peak of 97,000 individuals were recorded in January 2007. The highest counts for particular species included 9,400 Australasian Shoveler, 41,013 Pink-eared Duck (November 2006), 128 Freckled Duck, 2,100 Hardhead, 3,700 Whiskered Tern, 10,300 Blue-billed Duck, 19,400 Australian Shelduck (January 2007) and 15,400 Hoary-headed Grebe (March 2007). The WTP is often the site of some unusual sightings – a Grass Owl spent a month at the WTP in August-September 2006, and one was seen again in March 2007: this species has rarely been found in Victoria. For further information contact Richard.Loyn@dse.vic.gov.au Page Top
Development of a Method for Monitoring Deer in Forests Estimating the abundance of deer in forests by direct observation of animals is difficult because deer actively avoid people and the canopy prevents the use of aerial surveys. The most common method involves using an index of animal abundance based on repeated counts of deer faecal pellets in quadrats or along transects. Since 2002 ARI has been developing a deer monitoring protocol based on this method for use by Parks Victoria and the New Zealand Department of Conservation. Initially a number of pilot studies were conducted in forests of Victoria and New Zealand to determine the optimal sampling design for counting pellets. The resultant design involves the random placement of a minimum of 30 transects 150m in length within the area of interest, and placing 30 circular plots (1m in radius) evenly along the line. The numbers of pellets present within the circular plots are used to calculate an index of deer abundance. The accuracy of the protocol was tested by examining the relationship between calculated pellet indices and known densities of deer in enclosures. It was shown that as deer density increased the pellet index also increased. The protocol is currently being used to estimate changes in the relative abundance of deer in and around Victoria’s Alpine National Park and in New Zealand at sites where long-term intensive deer control is conducted. For further information contact: Dave.Forsyth@dse.vic.gov.au The following journal article is available: Forsyth, D.M., Barker, R.J., Morriss, G. and Scroggie, M.P. (2007) Modelling the relationship between fecal pellet indices and deer density. Journal of Wildlife Management 71(3): 964–970 Page Top

Surf Coast Shire Flora and Fauna Biodiversity The local government area of the Surf Coast Shire in south-western Victoria includes numerous reserves dedicated primarily to the preservation of native biodiversity. Nine of these reserves were recently the subject of flora and vertebrate fauna surveys to collect baseline information which was generally lacking for each specific location. The reserves varied in size from below 1ha to 50ha, and were mainly situated within, highly modified agricultural land or within urban areas of towns, the latter often relatively close to large tracts of extant native vegetation such as Heathy Woodland and Lowland Forest. Overall, these reserves embraced a variety of vegetation communities, including wetlands, sedgelands, grasslands and woodlands. In total, 16 Ecological Vegetation Classes were mapped, most of which rated High or Very High on the basis of their Bioregional Conservation Status (for the Otway Plains Bioregion) and vegetation quality — ten of these vegetation classes were considered to be Endangered, three Vulnerable, and one Depleted. Flora surveys also included Habitat Hectare assessments and compilation of flora species lists. Fauna surveys consisted of small mammal trapping, deployment of hair-tubes, spotlighting for possums and gliders, diurnal bird surveys, owl call-playback, microbat trapping and reptile searches. Most of the fauna species recorded are considered to be common and generally typical of the environments found within the reserves. A total of 23 mammal, 101 bird, six reptile and two frog species were recorded, including five species listed as threatened in Victoria: Pied Cormorant, Great Egret, Nankeen Night Heron, Latham’s Snipe and Rufous Bristlebird. These records, in conjunction with existing information, will enhance the management of these reserves. For further information contact Phoebe.Macak@dse.vic.gov.au Page Top

Movement Patterns of River Blackfish River Blackfish Gadopsis marmoratus occur in freshwater rivers and streams throughout south-east Australia and is a popular angling species that grows up to 60 cm in length. The daily movement patterns of this secretive native fish have been investigated in Armstrong Creek near Warburton, east of Melbourne. Small radio transmitters (2cm in length) were implanted into the abdominal cavities of fifteen individual fish. Three times a week over a 50 day period their precise daytime locations were determined using radio-tracking. Movements over a 24 hour period were also monitored by tracking locations each hour for three consecutive days and nights. Most River Blackfish remained inactive during daylight, staying within short lengths of creek (<20 m). A small number of fish displayed more active behaviour that was characterised by several rapid shifts in location followed by more sedentary phases. As sunset approached, fish began to move to other stream areas and continued moving around throughout the night until close to sunrise, when they returned to the area they occupied during daylight. Throughout the study, River Blackfish were located mostly within the deeper, slow flowing pool areas of the creek, but also used the shallow, faster flowing riffle and run habitats. During a flood period several fish moved among the vegetation of the inundated riparian areas. The range and abundance of River Blackfish has declined over the last 100 years. Although many stream rehabilitation programs now aim to conserve or restore suitable habitat conditions for River Blackfish, gaps in current knowledge of the ecological requirements of this species have limited their effectiveness. The observations of daytime ‘rest’ and nightime movement of River Blackfish, and the use of particular creek habitats, provides important additional information that will assist in the future development and implementation of targeted strategies for the species. Funding for this study was provided by Melbourne Water. For further information contact Wayne.Koster@dse.vic.gov.au A journal article based on this work is now available via the internet: Koster, W.M. and Crook, D.A. (2007) Diurnal and nocturnal movements of river blackfish (Gadopsis marmoratus) in a south-eastern Australian upland stream. Ecology of Freshwater Fish (OnlineEarly Articles) Page Top

Heat and Motion-Triggered Cameras as a Survey Tool Heat and motion-triggered cameras have been used in an increasing number of mammal surveys at ARI. Their functionality and reliability has much improved over recent years and they are now accepted as a realistic and viable means to test for presence and absence of mammals within a study site, as well as obtaining an estimate of detection probabilities against other survey methods for the more cryptic species found in Victoria. The cameras can be left unattended in the field for two to three weeks at a time, making them a cost affective tool even when considering the high purchase price. The operating units consist of a regular digital camera modified to respond to a sensor that detects changes in heat and motion as an animal moves across the field of view. The camera and sensor are housed in a weatherproof case designed to allow operation in most weather conditions. Units are usually secured to a tree, ensuring that there is a clear line of sight to bait that is placed within range of the camera. Bait is kept in a protective cage so it cannot be taken and consumed. The type of bait used is dependent upon the target species for the survey. The sensitivity of the cameras can be altered to suit a range of specifications, e.g. different animal groups. The cameras have recently been used to detect the presence of Spot-tailed Quolls in the Otways and East Gippsland, as a general survey tool in River Red Gum forest, and to detect the presence of Long-footed Potoroos in north-east Victoria after fire events and as a response to the control of introduced predators. The cameras are also useful for detecting the presence of introduced pests such as foxes, wild dogs, feral cats and deer. For further information contact Luke.Woodford@dse.vic.gov.au Page Top