The Australian Network for Plant Conservation Inc.

Australasian Plant Conservation

Originally published in Australasian Plant Conservation 17(2) August - September 2008, pp 42-43

Natural Temperate Grassland of the Victorian Volcanic Plain: a nationally threatened ecological community

John Vranjic
Department of the Environment, Water, Heritage and the Arts, Canberra. Email: john.vranjic@environment.gov.au

In June 2008, the Australian Minister for the Environment, Heritage and the Arts listed the Natural Temperate Grassland of the Victorian Volcanic Plain as a critically endangered ecological community under the Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act). This decision was made after extensive public and expert consultation and a detailed assessment by the Threatened Species Scientific Committee.

The Committee's assessment recognised that this grassland has been subject to a very severe decline in extent and a very severe reduction in its integrity, and has a very restricted distribution. The grassland was formerly extensive on the volcanic plain west of Melbourne but now occurs as mostly small, highly fragmented remnants in a landscape largely cleared for agriculture. Less than 5% of the grassland's original extent now remains.

The national listing recognises that the grassland's long term survival is under threat. The listing aims to prevent any further decline and to promote and assist recovery through landholder and community efforts.

Recognising the Listed Grassland

A detailed description of the Natural Temperate Grassland of the Victorian Volcanic Plain, featuring key diagnostic characteristics and condition thresholds is found in the listing advice and accompanying information brochure (EPBC Act Policy Statement 3.8).

In general, the listed grassland can be recognised by a combination of where it occurs, its vegetation structure and the types of native grasses present.

The Natural Temperate Grassland of the Victorian Volcanic Plain is restricted to western Victoria, primarily within the Victorian Volcanic Plain IBRA Bioregion. Some patches extend into the adjacent Victorian Midlands and South-east Coastal Plain bioregions.
The dominant vegetation layer is the ground layer, which is typically dominated by native grasses. A range of wildflowers and other herbs grow among the tussocks, including daisies, lilies, peas and orchids. Large shrubs and trees are absent to sparse, accounting for no more than 5% projective foliage cover or two mature trees per hectare.
The ground layer is usually dominated by one or more of the following perennial native grasses: Kangaroo Grass (Themeda triandra), Wallaby Grasses (Austrodanthonia species), Spear Grasses (Austrostipa species) or Tussock Grasses (Poa species). In some situations, the native grasses may be locally or temporarily replaced by native wildflowers.

The appearance of the ecological community can vary greatly depending on the time of year and management history of the site, for instance grazing and fire regimes. The description of the ecological community includes condition thresholds, described in the listing advice and information brochure, that aim to identify remnants of the grassland that are in good condition. Patches that do not meet the condition thresholds are not considered part of the listed ecological community and will not be affected by the EPBC Act. However, lower quality remnants may still be targets for funding and efforts to improve their condition.

Threatened Flora and Fauna

The Natural Temperate Grassland of the Victorian Volcanic Plain provides habitat for over 20 species of nationally threatened plants. These include the Matted Flax-lily (Dianella amoena), Plains Rice-flower (Pimelea spinescens subsp. spinescens) and Basalt Greenhood (Pterostylis basaltica).

Grassland remnants provide habitat for a diversity of animal species notably skinks, snakes, birds of prey and ground-dwelling birds. Some faunal elements have declined as the grassland itself has disappeared. For instance, grassland remnants now support few native mammals, even though bandicoots and wallabies were common in the past. Eight nationally threatened animal species occur in the grassland to some extent, and include the Striped Legless Lizard (Delma impar) and Growling Grass Frog (Litoria raniformis).

Critically Endangered Natural Temperate Grassland of the Victorian Volcanic Plain. Photo: Tim Allen

Threats and Conservation Actions

The main threats to the Natural Temperate Grassland of the Victorian Volcanic Plain are vegetation clearance (e.g. rock-crushing machinery that convert previously non-arable lands to cropping), fragmentation of remnants, inappropriate maintenance practices for remnants on roadside and railway verges, inappropriate grazing or fire regimes, inappropriate herbicide use, the application of fertilisers and weed invasion.

The listing of the grassland ecological community under the EPBC Act is intended to enhance its protection and future survival. National protection means any new or intensified activities that are likely to have a significant impact upon the listed grassland should be referred to the Commonwealth Minister for the Environment, Heritage and the Arts to assess the nature of any environmental impacts and seek approval for the action. Activities likely to require approval include, but are not restricted to; clearing remnants of the ecological community; creating new roads, tracks or fuel breaks; significant changes to an existing management regime (such as converting from mowing/slashing to herbicide use or substantially intensifying stocking rates on the grassland); introducing fertilisers or other chemicals to native grassland remnants indiscriminately or where none were previously applied, or introducing new, potentially invasive exotic pasture species in or near to remnants.

Exemptions under the EPBC Act mean that the listing of the Natural Temperate Grassland of the Victorian Volcanic Plain will not prevent land managers from continuing to use their land in the same way as before, providing that they do not significantly change or intensify their activities and the activity is lawful.

A key message to landholders is that, if they retain a high quality patch of the listed grassland on their property then they should be congratulated for good management and be encouraged to continue their existing management practices. Incentives are available to help landholders manage their land to achieve good conservation outcomes, for instance through Australian Government funding programs such as Caring for our Country and the Environmental Stewardship Program, or through State Government initiatives.

Another key message is that there are benefits to long-term protection of native biodiversity. Native vegetation remnants, such as the listed grassland, are naturally resilient to weeds and provide ecosystem services across an area of Australia regularly hit hard by drought, including retention of water and soil nutrients, reducing erosion and salinity, and carbon storage.

The conservation advice for the listed grassland suggests actions to encourage its recovery. A comprehensive recovery plan has also been recommended for the region.

Further Information

Considerable information is available from the website of the Department of the Environment, Water, Heritage and the Arts <www.environment.gov.au>.

The listing advice, conservation advice and an information brochure for the listed grassland are available at <www.environment.gov.au/cgi-bin/ sprat/public/publicshowcommunity.pl?id=42>.

Information about referrals and approvals under the EPBC Act is available at <www.environment.gov.au/epbc/approval.html>.

Details about funding schemes are available at <www.nrm.gov.au/ funding/future.html>.