Burt Plain
Bioregional Description
One of the distinguishing features of the Burt Plain Bioregion is the predominance of earthy, alluvial soils as opposed to sandplains and sand dunes. The bioregion is broadly characterised by plains of Acacia shrubland, tussock and hummock grasslands, Acacia and Eucalyptus woodlands, and mountain ranges in the east, north and west of the bioregion. Most of the bioregion (>80%) is devoted to pastoralism. The Burt Plain Bioregion comprises four subregions all of which occur entirely within the Northern Territory.
Special Values
The Burt Plain Bioregion supports some of Australia’s best developed and most extensive mulga woodlands. It also supports resident populations of some plant and animal species that are significant at the Northern Territory and national level, including 13 threatened species. From a national perspective there are no extant vertebrate species that are endemic to the bioregion. However, there are three plant taxa endemic to the Burt Plain Bioregion (Ipomoea sp. Stirling (P.K. Latz 10408), Ptilotus aristatus var. exilis and Ptilotus aristatus var. stenophyllus). At the Northern Territory level, there are 7 plant taxa that have been recorded only from the Burt Plain Bioregion, but once again there are no extant vertebrate animal species that are unique to the bioregion.
Summary of Overall Condition and Trend
As with other central Australian bioregions, the overall condition of the Burt Plain Bioregion is masked by a very strong rainfall effect, with degradation sometimes difficult to detect following a series of good seasons. However, much of the bioregion has been impacted by a range of pervasive factors such as grazing by livestock and/or feral animals, feral predators and weed infestations. Many of these detrimental factors were probably most pernicious and had the most impact in the first few decades following European settlement, and some may now have improved or stabilised, such that there may be some reversal in land condition in the bioregion.
The Burt Plain Bioregion has suffered substantial losses of its mammal fauna over the last century, while there are ongoing declines of some bird and mammal populations. Exotic predators are widespread and there are fifteen declared weed species currently listed under the Northern Territory Weeds Management Act 2001 which are known to occur in the Burt Plain Bioregion. Other exotic plants species, most notably buffel and couch grass, also pose significant threats to some habitats.
Subregions of the Burt Plain Bioregion are scored a continental stress class of 3 (BRT3), 4 (BRT1, BRT2), and 5 (BRT4).
Summary of Priority Management/Conservation PrioritiesThe bioregion is currently very poorly reserved (<1% of bioregional extent), and most ecosystems are not well represented in the reserve network. Additional reservation would be necessary to achieve a regional CAR reserve system. However, at least as effective for biodiversity conservation would be integrated management (across all tenures) of weeds, feral animals and fire, and implementation of some off-reserve conservation strategies and actions on pastoral lands. Such management actions will require additional resources and effective communication and capacity building amongst pastoral and Aboriginal landholders.
Wetlands
Nationally important wetlands
- While no wetlands are currently listed in the ‘Directory of Important Wetlands in Australia’ (DIWA) or under the ‘Convention on Wetlands of International Importance’ (Ramsar Convention), some significant wetlands in the Burt Plain Bioregion have been identified as meeting certain DIWA criteria and potentially meeting some Ramsar criteria.
Other wetlands of subregional significance
- A range of generally small swamps, ephemeral watercourses and rockholes occur in the Burt Plain Bioregion. Important wetlands of the bioregion include Stirling Swamp, and the springs and waterholes of the Dulcie Ranges.
For more information on arid wetlands of the NT refer to our arid wetlands page.
Riparian Zones
The bioregion contains some ephemeral watercourses, which are generally in fair to good condition, but are afforded little protection from a range of threatening processes including the impacts of livestock and/or feral animals and weed infestation. The major river systems occurring in the bioregion include parts of the Plenty, Hanson, Sandover and Lander Rivers.
Ecosystems at Risk
No ecosystem has formally been listed as threatened, but wetland and riparian environments are likely to be impacted by livestock, feral animals and weeds. Other ecosystems are being altered by changed fire regimes. Part of the resource assessment of the Burt Plain Bioregion currently being undertaken is to identify important habitats through the analysis of available flora and fauna information (including pre-existing data and data collected from systematic wildlife surveys currently being undertaken), together with an assessment of their conservation values and the threatening processes that impact on these values.
Many species have been lost from this bioregion over the last 150 years. Of those that persist, 13 species are currently listed as threatened at the National and/or Territory level, including the southern marsupial mole (Endangered at the Federal level); Ipomoea sp. Stirling (P.K. Latz 10408), Macrozamia macdonnellii, great desert skink, red goshawk, princess parrot, mulgara, bilby and black-footed rock-wallaby (Vulnerable at the Federal level); common brushtail possum (Endangered at the NT level); and Eleocharis papillosa, bustard, emu and painted snipe (Vulnerable at the NT level).
Amongst these threatened species, predation is probably an important threat for the bustard, mulgara, southern marsupial mole, common brushtail possum and black-footed rock-wallaby; changed fire regimes for Ipomoea sp. Stirling (P.K. Latz 10408), bustard, emu, princess parrot, mulgara and common brushtail possum; grazing impacts by livestock and/or feral animals for Ipomoea sp. Stirling (P.K. Latz 10408), bustard, emu, princess parrot, mulgara, common brushtail possum and black-footed rock-wallaby; weed infestation for Eleocharis papillosa; and changes in wetlands across its entire range for the painted snipe.
Number of taxa in the Burt Plain Bioregion currently listed as threatened at national and/or Northern Territory level (nb this table includes only species definitely recorded from the bioregion (rather than putative occurrences based on modelling) and presumed to be still extant in the bioregion).
| taxa | National | Northern Territory | ||
|---|---|---|---|---|
| endangered | vulnerable | endangered | vulnerable | |
| plants | 0 | 2 | 0 | 3 |
| reptiles | 0 | 1 | 0 | 1 |
| birds | 0 | 2 | 0 | 5 |
| mammals | 1 | 3 | 1 | 3 |
Other Flora Values for Eucalypts and Acacias
Endemism
- At a national level, there are no eucalypts or acacias endemic to the Burt Plain Bioregion.
Richness
- The subregions of the Burt Plain Bioregion have only moderate richness of Acacia (11-27) and Eucalyptus (18-49) species.
Little change between Atlases, although notable decline for hooded robin. Other sources indicate substantial declines over the last 100 years for a broad range of bird species, probably associated with vegetation change brought about through the impacts of pastoralism and feral animals, weed infestations, changed fire regimes, and possibly feral predators.
Mammals
The Burt Plain Bioregion has suffered substantial losses of its mammal fauna. Of 55 native mammal species recorded, at least 15 are extinct or no longer occur in the bioregion, while several others have suffered population declines.
Management Responses
Reserve Consolidation
The bioregion is currently very poorly reserved, with especially poor representation of the dominant mulga woodlands. There are five small conservation or historical reserves and one national park (Dulcie Ranges National Park) comprising 0.26% of the area of the bioregion. These small reserves would not be expected to contain a high proportion of the plant and animal species found across the bioregion. The largest of the protected areas, the Dulcie Ranges National Park, supports 22% of animal species found in the bioregion but on 6% of plant taxa of the bioregion.
Off Park Conservation for Species and Ecosystem Recovery
More detailed information is required on the habitats of the Burt Plain Bioregion and for a range of mulga-associated biota, to determine the potential threatening processes that may impact on them and to understand the causes of some apparent population declines (e.g. hooded robin), and devise management solutions.
Integrated NRM
A preliminary report directed towards a resource assessment of the Burt Plain Bioregion was completed in 2006. This included a compilation of available data and information on the bioregion’s flora and fauna to help identify gaps in our current knowledge of the biodiversity of the bioregion, and assist with the design and implementation of wildlife surveys across the area. The collation of existing information and data is presented in a report titled ‘Preliminary Report: Towards a Resource Assessment of the Burt Plain Bioregion for Conservation Planning’ prepared by Helen Neave, Ben Sparrow and Bretan Clifford.
Preliminary Report: Towards a Resource Assessment of The Burt Plain Bioregion for Conservation Planning
Further Information and Gaps
Major Data Gaps and Research Priorities for Bioregion
A comprehensive biodiversity survey is needed to identify conservation values and options for their management. Furthermore, more information is required on the response of biodiversity to a spectrum of possible management options. Management would also benefit from more detailed environmental mapping, in particular vegetation mapping at the scale of 1:250,000 or better.
