The Corangamite Region is covered by five ecological zones (bioregions), these are the Victorian Volcanic Plain, the Otway Plain, the Otway Ranges, the Warrnambool Plain and the Central Victorian Uplands. Each of these zones has vegetation communities that reflect the conditions within these zones.
Native vegetation is a fundamental part of the landscape. It is an important element in all ecological processes and it plays a major part in our everyday lives. The region’s native vegetation requires proper management, at both a regional, local and site-specific scale to ensure its survival.
Native vegetation in the Corangamite region has undergone a major change since European settlement, with less than 25% of the region’s original vegetation remaining. Native grasslands and grassy woodlands have been reduced to an estimated 1% of their former extent. The region has significant areas of remnant vegetation in protected reserves such as National Parks but most of the estimated 66,000 hectares of remnants on private land are under some form of pressure. These changes are most evident in areas that have been cleared for agriculture.
The loss of native vegetation has contributed to the main natural resource management problems in the region. Loss of biodiversity, salinity, soil erosion, poor water quality and the spread of exotic species are just some of the problems that have emerged. As well as aesthetic and landscape significance, native vegetation is a vital component in the sustainability of our landscapes and a key factor in the functioning of natural ecosystems.
The Wadawurrung Healthy Country Plan says “Our inland country includes western volcanic plains and grasslands, with their temperate grasslands and grassy eucalypt woodlands once had enough food and resources for us to live here permanently all year in our stone huts as a community in family groups. The grasslands were full of food grasses, and our women harvested roots and tubers, like Murnong and bulbine lily with their digging sticks. Our Country is home to many different types of snakes, lizards, frogs, moths, birds and mammals. Kwenda (Bandicoot) or Yoorn (spotted tail quoll) was once here as was the eastern barred bandicoot who helped our women in digging and tilling the soil to increase the growth of Murnong, helping our women to till the soil but now are extinct or rarely seen in this landscape.”
Assessment of current condition and trends
The quality and extent of native vegetation affects its ability to carry out important environmental functions and provide other values such as nature-based tourism. Of the five bioregions within the Corangamite region, the Victorian Volcanic Plain, Warrnambool Plain and Otway Plain bioregions are amongst the most cleared in the State. The Central Victorian Uplands bioregion is moderately cleared, and the Otway Ranges bioregion is amongst the least cleared in Victoria.
In 5.92% of the entire Corangamite region, the Ecological Vegetation Classes (EVC’s) that exist are classified as endangered. A further 4.24% of the Corangamite region is classified as vulnerable. A number of Ecological Vegetation Classes within the region are now presumed to be extinct, these include Coast Gully Thicket, Plains Grassy Wetland and Scoria Cone Woodland. There are a number that are currently endangered, including:
- Plains Sedgy Wetland (EVC 647)
- Aquatic Herbland (EVC 653)/Plains Sedgy Wetland (EVC 647) Mosaic
- Grassy Woodland (EVC 175)
- Lignum Swamp (EVC 104)
- Plains Grassland (EVC 132)
- Floodplain Riparian Woodland (EVC 56)
- Grassy Forest (EVC 128)
- Damp Heath Scrub (EVC 165)
- Swampy Riparian Woodland (EVC 83)
- Coastal Alkaline Scrub/Calcarenite Dune Woodland (EVC 858)
- Stream-bank Shrubland (EVC 851)
- Swamp Scrub, (EVC 53) and
- Damp Sands Herb-rich Woodland (EVC 3)
Of all the landscape systems, the Bellarine-Surf Coast has the largest relative percentage of land where the Ecological Vegetation Classes are classified as endangered (13.23%), followed by Geelong City landscape system (11%). The landscape system with the lowest percentage of EVCs classified as endangered is Heytesbury (1.88%). Conversely, of all the landscape systems, the Heytesbury region has the greatest percentage of land where the EVCs are classified as vulnerable (14.71%). This is followed by the Otway Coast, with 6.01% of the landscape area falling into vulnerable Ecological Vegetation Classes.
Most of the current losses of native vegetation in the region may be attributed to loss in condition (80%) with 20% being removed through clearing (VEAC, 2011). The survival of threatened flora and fauna and ecological communities depends a great deal on the health of native vegetation, and the continuation of other important habitats that are threatened by human activities and vulnerable to climate change stress.
For more information on threatened ecological communities and threatened species under the EPBC Act, see Relevant Biodiversity Documents under the Biodiversity tab.
Major threats and drivers of change
The consequences of removing native vegetation have been well documented. These include the loss of biodiversity, increased salinity, soil erosion, deteriorating water quality in our rivers, creeks and wetlands, and the consequent losses in farm productivity. Mismanagement of native vegetation, such as the introduction of environmental weeds, has also led to examples of detrimental impacts.
Land clearing is one of many factors contributing to the loss, fragmentation and degradation of native vegetation in the Corangamite region. Other factors threatening native vegetation include:
- pest plants and animals
- disturbance such as fire or floods
- inappropriate land use and/or land management practices
- climate change.
It is expected that climate change will impact the region’s native vegetation through modifications to vegetation communities, such as loss of particular plant species and changes to community structure, as a result of higher temperature and lower rainfall, changes to natural fire and flooding regimes and climatic conditions favouring new and established weed species.
DELWP’s Biodiversity Response Planning (BRP) is a new state-wide, area-based approach to biodiversity conservation. It has been designed to strengthen alignment, collaboration and participation between government agencies, Traditional Owners, non-government agencies (NGOs) and the community. Response planning in each area shares the same key elements:
- situation analysis (looking at what the current state of biodiversity and its threats are in each region)
- cataloguing what actions are currently taking place (a list of who’s doing what work where)
- gap analysis (looking for what’s missing and what else needs to be done)
- discussing options (everyone in the network will talk about possible actions to take), and
- determining priorities (what’s the most urgent thing to address).
The BRP maps will guide where biodiversity actions should occur, whether this is through voluntary efforts or as a result of future investment by the Government or other sources. The maps of agreed priorities and other outputs of these collaborative processes will be publicly available and regularly updated. The aim of BRP is to get the best possible outcome for biodiversity overall. Biodiversity Response Planning is how DELWP is implementing Victoria’s plan for Biodiversity, Protecting Victoria’s Environment – Biodiversity 2037, in different places.