Characteristics of Threatened Communities

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Flora and Fauna Guarantee Act 1988 – Threatened List

Characteristics of Threatened Communities

To help field recognition of the various communities of flora and fauna currently listed as ‘threatened’ under the FFG Act, their distinguishing characteristics are set out below. This information is provided by the FFG Scientific Advisory Committee and is based on the attributes used to define those communities when they were added to the Threatened List.

Where a scientific name has been revised since a community was originally listed, the name currently in use has been included together with that used originally (e.g. Astelia alpina = A. alpina var. novae-hollandiae : Astelia alpina was the name used originally, A. alpina var. novae-hollandiae is the current name). Current botanical names follow those used in A Census of Vascular Plants of Victoria Walsh & Stajsic (ms Feb 2013). Community descriptions are in alphabetical order.

Alpine Bog Community

The Alpine Bog Community is commonly described as bog or moss bed with the dominant vegetation including Spreading Rope-rush (Empodisma minus), Candle Heath (Richea continentis), Snowgrass (Poa costiniana), Sphagnum moss (Sphagnum spp.), Alpine Baeckea (Baeckea gunniana), Silver Astelia (Astelia alpina = A. alpina var. novae-hollandiae) and Fen Sedge (Carex gaudichaudiana).

This community appears to be restricted to permanently wet sites along drainage lines and valley floors with a low to moderate slope and hillside slopes in the vicinity of springs. Sphagnum moss is a characteristic feature and can form an extensive cushion or terrace, absorbing and restricting water flow. Peat soils accumulate through the slow decomposition of the sphagnum and other plant material. Extensive peat soils can be present depending on the substrate on which the bog has formed. On rocky areas the peat/bog may only be a metre or so deep, in other areas the peat formation can be several metres deep.

The Alpine Bog Community is represented in Victoria by a number of fragmented and isolated sites scattered across the Australian Alps and occurring in alpine, subalpine and montane environments typically above the climatic tree-line (at or above 1200 m ASL). The community may also occur at lower altitudes in areas known as ‘frost hollows’ which prevent the establishment of trees within the community.

Alpine Snowpatch Community

Alpine Snowpatch Community includes two main vegetation associations: Short-turf Snowpatch and Diuturnal Snowpatch. Characteristic species found in Short-turf Snowpatch includes sedge (Carex hebes) and a variety of small herbaceous plants with tussock-forming Poa virtually absent and the plants rarely exceeding 10 cm in height. Diuturnal (long-continuing) Snowpatches occur on higher slopes and retain snow for longer periods, with the upper areas of these communities dominated by Silver Snow Daisy (Celmisia asteliifolia). On the downslope areas where the soil profile can be deeper, Snowgrass (Poa fawcettiae) gradually becomes dominant.

Snowpatch vegetation communities are rare in Australia, typically occurring on the steeper sheltered slopes, often with a south-eastern aspect, where snow can persist into warmer months of the year (December and January). Snowpatches vary considerably in shape, size and permanency: some last only for weeks, others persist for years. Their vegetation composition varies considerably, being strongly influenced by site characteristics and how long snow persists. Short-turf Snowpatch tends to occur on the lee side of low ridges where snow accumulates on moderate slopes of sheltered aspect and remains for one to two months longer than on adjoining areas. This type is widely distributed across the Bogong High Plains on basaltic and metamorphic parent material. Diuturnal Snowpatch is restricted to the lee side of the highest ridges and large concave sheltered slopes. At these sites snowmelt is typically not complete until midsummer; very few species are capable of existing at sites with such short growing seasons.

Butterfly Community No. 1

Butterfly Community No.1 is a community characterized by the presence of several species of butterfly. The most important of these are the Small Ant-blue (Acrodipsas myrmecophii) and the Large Ant-blue (Acrodipsas brisbanensis cyrilus) but the list also includes other species, such as the Southern Purple (Genoveva) Azure (Ogyris genoveva araxes), Northern Dusky Blue (Candalides hyacinthus simplex) and Miskin’s or Wattle Blue (Theclines miskini miskini), together with the ant Iridomyrex nitidus on which the ant-blues depend. Several of these species, including both ant-blues, are rare throughout their species’ range. The ant-blues are known from only one locality in Victoria, and are listed as threatened taxa under the FFG Act. The Miskin’s or Wattle Blue is not common in Victoria, though more abundant through its wider range.

Characteristic vegetation is a mosaic of dry open forest and woodland of eucalypts, such as Broad-leaved Peppermint (Eucalyptus dives), Long-leaved Box (E. goniocalyx), Messmate (E. obliqua) and Red Stringybark (E. macrorhyncha) with an understorey with both grasses and shrubs. Typical understorey species are Poa grasses, Rock-ferns (Cheilanthes spp.), Common Heath (Epacris impressa), Groundsels (Senecio spp.) and Mountain Grevillea (Grevillea alpina). The main food plants on which these butterflies lay their eggs are tree lichens, rock lichens and fungi.

Butterfly Community No.1 is currently known only from Mt Piper, a solitary conical hill that rises 230-456 m above a plain between the Tallarook and Mt William ranges in north-central Victoria.

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