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 2009 Index of Wetland Condition Mapping Vegetation Extent and Condition Across Victoria Shorebirds and Benthos at the Western Treatment Plant Waterbird Numbers at the Western Treatment Plant Development of a Method for Monitoring Deer in Forests 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)

For information on previous projects, such as biodiversity in the Surf Coast Shire and River Blackfish movement, see the Mapping and Measuring Biodiversity - past projects page.

Annual Summer Waterfowl Count 2009 The Victorian Summer Waterfowl Count has provided information on the distribution and abundance of protected species (particularly Freckled Duck Stictonetta naevosa), game ducks and waterbird breeding since 1987. Counts take place over a nine day period in late February-early March by DSE and volunteers from Field and Game Australia. The data collected in these counts are used to guide management options for the year’s duck hunting season. The number of wetlands surveyed varies each year, with some dry wetlands excluded because they are known to have been dry for several years. Results from the 2009 count included: 161 wetlands surveyed 64% of wetlands surveyed were dry 79,600 game ducks recorded 38,200 protected waterfowl (swans, coot, grebes and certain ducks) recorded Although numbers for some species have increased since the 2008 SWC, overall there has been a decline since 1987 in waterfowl numbers recorded during these counts. Drought conditions are thought to have had an impact on waterfowl numbers due to fewer wetlands containing enough water to support populations. In addition, species that usually come to Victoria to breed may have instead done so in other states that have experienced good summer rains. After two years of cancelled duck hunting seasons (due to low numbers of game ducks) a restricted hunt went ahead in 2009. Three species of game duck (Pink-eared Duck, Hardhead and Australasian Shoveler) were excluded from hunting as extremely low numbers were recorded in the 2008 SWC and in aerial surveys across eastern Australia in spring 2008. All count data are collated at ARI before being stored within the DSE Atlas of Victorian Wildlife database. For further information contact Daniel.Purdey@dse.vic.gov.au Page Top
Index of Wetland Condition The Department of Sustainability and Environment developed an Index of Wetland Condition (IWC) in November 2005 for use in Victoria. The IWC measures aspects of the wetland’s soils, water, plants and the wetland catchment. The method is designed for naturally-occurring wetlands without a marine hydrological influence. The development of the IWC and its measures (indicators) are explained in the report: Index of Wetland Condition - Conceptual framework and selection of measures. Other methods for assessing the condition of wetlands and streams are described in the report: Index of Wetland Condition - Review of wetland assessment methods. The review summarises wetland assessment methods reported in the literature from Australia and overseas and highlights examples of how aspects of wetland assessment and monitoring have been undertaken that have most relevance to Victoria. The IWC has undergone testing to determine if it measures condition consistently between different users, at different wetland types and at wetlands that range from very poor to excellent condition. This report documenting the findings of the testing program is in preparation and will be added to this page when published. The IWC was modified slightly in 2008 following the testing and a data management system developed to store and manage IWC data. An IWC wetland base maps tool was produced to generate wetland maps used with the IWC method. The maps may also be useful for other purposes. DSE is coordinating an assessment of the condition (health) of wetlands across the state using the IWC. Assessments have commenced and will conclude in mid December 2009. Approximately 750 wetlands have been selected for this year’s assessment. Sites were selected based on environmental, cultural and scientific values. Overall, the assessments will improve our understanding of wetland condition across the state. The data will also help Catchment Management Authorities (CMAs) better target government programs and funding which can assist land managers with wetland management. For further information see the IWC website or 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 Update September 2009 (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
Shorebirds and Benthos at the Western Treatment Plant The Western Treatment Plant (WTP) is managed by Melbourne Water to treat over half of Melbourne’s sewage. The area is also an important habitat for shorebirds, with some species migrating each year to Australia from Arctic breeding grounds up to 12,000 km away. These extraordinary migrations are fuelled by large amounts of food; birds need to build up enormous fat reserves to migrate successfully. Shorebirds are also known as “waders” because they forage by wading in mud and shallow water. They are attracted to the WTP because it provides rich foraging habitat, with very high densities of burrowing invertebrates (“benthos”) found in tidal flats along the foreshore. It is likely that decades of effluent discharges from the WTP have enriched this habitat. Some shorebirds also feed in the shallower freshwater ponds of the WTP. Melbourne Water has commissioned ARI to undertake research to help conserve the shorebirds and their habitat. Protecting or enhancing shorebird habitats is challenging, as the tidal flats and freshwater wetlands in which they live are complex, dynamic habitats. An ongoing study is investigating the relationship between the abundance of shorebirds and their food source at the WTP. Repeated shorebird surveys were coupled with surveys of abundance of their benthic prey. These studies showed that shorebird abundance in the WTP is strongly correlated with abundance of benthos. Benthos abundance was found to fluctuate locally over time, and shorebirds moved their feeding grounds in response. Many questions still need to be answered. For example, why does abundance of benthos vary so much over time? What prey densities are needed to make a foraging site suitable for shorebirds? With a more complete understanding of the relationships between shorebirds and their prey, we will be better placed to ensure that their habitats are managed appropriately. For further information contact Danny.Rogers@dse.vic.gov.au The following report is available: ARI Technical Report 169 - Relationships between shorebird and benthos at the Western Treatment Plant (PDF - 1.3 MB) 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 2007-2008 financial year a peak of 80,500 individuals were recorded in January 2007. The highest counts for particular species included 7,270 Australasian Shoveler, 13,350 Pink-eared Duck, 4,860 Hardhead, 1,550 Whiskered Tern (November 2007), 58 Freckled Duck, 5,300 Blue-billed Duck, 21,000 Australian Shelduck and 14,260 Hoary-headed Grebe (January 2008). The WTP has supported ~70% of waterfowl counted in Victoria in recent surveys (Summer Waterfowl Count 2009 and aerial survey 2008). 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
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