Commonwealth of Australia
Inclusion of ecological communities in the list of threatened ecological communities under section 181 of the Environment Protection and Biodiversity Conservation Act 1999 (EC 105)
I, TONY BURKE, Minister for Sustainability, Environment, Water, Population and Communities, pursuant to paragraph 184(1)(a) of the Environment Protection and Biodiversity Conservation Act 1999, hereby amend the list referred to in section 181 of that Act by:
including in the list in the endangered category
Monsoon vine thickets on the coastal sand dunes of Dampier Peninsula
as described in the Schedule to this instrument.
Dated this…..................14th..................day of….............February..............................2013
Minister for Sustainability, Environment, Water, Population and Communities
Monsoon vine thickets on the coastal sand dunes of Dampier Peninsula
The Monsoon vine thickets on the coastal sand dunes of Dampier Peninsula ecological community (hereafter referred to as the Dampier Monsoon Vine Thickets or the ecological community) represents certain occurrences of monsoon vine thickets in the south-west Kimberley region of Western Australia (within the Dampierland bioregion). The ecological community is predominantly restricted to the coastlines of the Dampier Peninsula from Broome in the south to One Arm Point in the north and on the north-eastern coast of the Peninsula from One Arm Point to Goodenough Bay.
The Dampier Monsoon Vine Thickets is particularly associated with Holocene sand dunes and other coastal geological formations. The ecological community occurs as discontinuous patches of dense vegetation usually occurring on the leeward slopes and swales and sometimes the exposed crests of the coastal Holocene dune systems. Some patches may extend landward onto the red-soil pindan plains. Outliers may occur on different substrates where other factors, such as moisture availability and protection from fire support the ecological community.
The Dampier Monsoon Vine Thickets contains deciduous, semi-deciduous and evergreen perennial flora species depending on the landscape position and microclimate. Patches in the higher rainfall zone tend to be the most species rich, have a dense canopy and be characterised by co-dominant evergreen tree species in the overstorey. The ground layer is often sparse or absent. Patches of the ecological community in the lower rainfall zone, as well as those generally situated on low dunes and other exposed locations, are mostly depauperate in evergreen trees and have an open canopy and shrubby structure.
The Dampier Monsoon Vine Thickets is naturally fragmented due to landscape position, fire regimes, hydrological requirements and availability of suitable habitat; however, it functions as a network ecosystem. The ecological community has an abundance of fruiting plants dependent on the movement of frugivorous fauna between patches for seed dispersal, maintaining essential plant species migration and gene flow. The ecological community also shares flora species with some adjacent ecological communities. For example, Acacia spp are common in the ecological community and the adjacent pindan vegetation.
The canopy of the ecological community can be variable and is typically dominated by a mix of several tree or tall shrub species and may include genera such as Acacia, Corymbia, Eucalyptus, Hakea and Melaleuca. A patch can be occasionally dominated by a single tree species such as ebony wood or Celtis philippensis (goolnji).
In exposed beach and headland positions, the canopy of the ecological community is generally low, but increases in height where large sand dunes provide more sheltered valleys on the swale or lee side. Emergent tree species may extend beyond the canopy. The mid layer, when present, can contain scattered semi-deciduous fruiting shrubs and small trees.
The ground layer of the Dampier Monsoon Vine Thickets is generally shaded and often with a layer of leaf litter or dark organic matter on the soil surface. Where the canopy is mostly intact, the ground layer is usually very sparse. Patches with closed canopies typically lack native grass or fern species in the interior. Annuals are mainly absent in closed canopy patches particularly during the dry season. Where the canopy is more open, annuals may occur during the wet season.
Vines/climber species can be present in all layers of the ecological community. While vines are not the dominant component of the ecological community, they typically comprise up to 25% of the native perennial plant species richness. Vine species are often inconspicuous, particularly during the dry season when they may be leafless or die back to rootstocks.
The Dampier Monsoon Vine Thickets exhibits the following key diagnostic characteristics:
· Distribution occurs within the Dampierland bioregion – mostly in the Pindanland subregion DL2 (Interim Biogeographic Regionalisation for Australia, Version 7).
· Mainly restricted to the deep white or grey calcareous sands of the coastal Holocene dunes of the Dampier Peninsula.
· Mainly occurs within the swales, in the leeward side of the coastal dunes and occasionally on the crests of these dunes and other coastal landforms such as: beach fronts, sand-spit headlands and storm ridges with intertidal flats.
· Outliers may occur on different substrates within the DL2 subregion.
· The overstorey (canopy) typically shows the following features:
o Typically ranges from three to nine metres tall and may consist of trees, tall shrubs and/or climbers/vines.
o Tree canopy composition is variable but the most common species are typically one or more of the taxa Bauhinia cunninghammi (jigal, joomoo), Celtis philippensis (goolnji), Diospyros humilis (ebony wood), Exocarpos latifolius (jarnba, mistletoe tree), Grewia breviflora (goolmi, currant/coffee fruit), Mallotus nesophilus (yellow ball flower), Mimusops elengi (joongoon, mamajen), Sersalisia sericea (mangarr), Terminalia ferdinandiana (gabiny, gubinge, kabiny) and Terminalia petiolaris (blackberry tree, marool, narwulu).
· The understorey typically shows the following features:
o Shrub and small tree species when present include: Breynia cernua, Bridelia tomentosa, Caesalpinia major (goolyi), Croton habrophyllus (ankoolmarr), Dodonaea platyptera, Flueggea virosa subsp. melanthesoides (snowball bush) and Santalum lanceolatum (tropical sandlewood).
o Ground layer is generally sparse to absent but may contain a variety of herbaceous species depending on seasonal conditions, site characteristics and canopy density.
o Native grass species are uncommon but may occur on the edges of vine thicket patches or in open groves. When present they typically include annual species such as Perotis rara (comet grass) and Setaria apiculata (pigeon grass).
· Vines and creepers are often, but not always, present in the overstorey and/or understorey and when present include: Abrus precatorius (crab’s eye bean), Adenia heterophylla subsp. australis, Capparis lasiantha (ngoorla, bush caper), Jacquemontia paniculata, Jasminum didymum, Tinospora smilacina (oondal, snake vine) and Tylophora cinerascens (oyster-catcher bill).