Finke
Bioregional Description
The Finke Bioregion is a geomorphologically complex and varied area of low sandstone ranges, weathered tablelands and rounded metamorphic hills, laterite-capped mesas, saline depressions and sandplains. Dominant vegetation includes hummock grasslands, Acacia shrublands and saltbush/bluebush open shrublands. The Finke Bioregion includes three subregions.
Special values
The Finke Bioregion is notable for its environmental diversity. It includes one nationally significant wetland system, and supports resident populations of some plant and animal species that are significant at the Northern Territory and national level, including 14 threatened species. From a national perspective there are no extant vertebrate species and only one known plant taxon (Sida sp. Horseshoe Bend (R.E. Winkworth 798)) endemic to the Finke Bioregion. At the Northern Territory level, there are 26 plant taxa that have been recorded only from the Finke 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 Finke Bioregion is masked by a very strong rainfall effect, with degradation sometimes difficult to detect after a series of unusually good years. However, much of the region has been substantially degraded or altered by a range of pervasive factors. Over-grazing by livestock and/or feral animals (principally rabbits, camels and horses) has degraded many areas, especially riparian areas, natural waterholes, and fertile lowlands. Foxes and feral cats are widespread and have taken a heavy toll on the native fauna, especially critical-weight range mammals and ground-dwelling birds such as the night parrot. There are major weed infestations, most notably of buffel and couch grass, and of athel pine in riparian systems.
Many of these detrimental factors were probably most pernicious and had most explosive impacts in the first few decades following European settlement, and some may have now improved or stabilised (e.g. vegetation change caused by rabbits; some improvements in land husbandry within the pastoral industry), such that there may be some reversals in the general pattern of decline.
All subregions of the Finke Bioregion are scored as continental stress class 5, although this rather gilds the lily. Class 3 is probably more apt.
Summary of priority management/conservation priorities
The bioregion is currently very poorly reserved (<1% of bioregional extent), and most ecosystems are not 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 agreements and actions on pastoral lands. Such management actions will require additional resources and some capacity building, especially among Aboriginal landholder groups.
Wetlands
Nationally important wetlands
- The Karinga Creek palaeodrainage system occurs in the far west of this bioregion. It comprises a series of permanent springs, ephemeral seepage creeks and ephemeral lakes formed by discharge from the central Australian groundwater basin, supplemented occasionally by irregular heavy rainfall events. When full, the lakes are important for waterfowl and some shorebirds, especially as stop-over points for the latter during their dispersal across Australia. The system is also important as a research and reference site for hydrogeology and palaeoclimate.
Other wetlands of subregional significance
- A range of wetlands of subregional significance have been identified. Most of these are near permanent waterholes in the major intermittent/ephemeral river systems, and the broad reaches of the river systems themselves.
For more information on arid wetlands of the NT refer to our arid wetlands page.
Riparian zones
The bioregion includes most of the catchment of the Finke River, other than its headwaters. A range of pervasive factors degrade riparian zones across this bioregion. Most riparian areas are unfenced and trampled or grazed by livestock and feral animals. There are at least localised patches of serious weed infestation in the bioregion, most notably of buffel grass, couch grass and athel pine.
Ecosystems at risk
No ecosystem has formally been listed as threatened, but wetland and riparian environments are at risk from ongoing degradation by livestock, feral animals and weeds. Other ecosystems are being altered by changed fire regimes. Few habitats of high importance in the Finke Bioregion are not subject to a range of threatening processes. Several important habitats have been identified from an analysis of available flora and fauna information (including pre-existing data and data collected from a recent systematic wildlife survey), together with an assessment of their conservation values and the threatening processes that impact on these values.
Species at risk
Many species have been lost from this bioregion over the last 150 years. Of those that persist, 14 species are currently listed as threatened at National and/or State/Territory level. Amongst these, feral predators are probably an important threat for the bustard, fawn hopping-mouse, plains rat, mulgara, southern marsupial mole and black-footed rock-wallaby; changed fire regimes for Acacia latzii, bustard, emu, princess parrot, slater's skink, common brushtail possum and mulgara; grazing impacts by livestock and/or feral animals for Acacia latzii, bustard, emu, princess parrot, slater’s skink, plains rat, common brushtail possum, mulgara and black-footed rock-wallaby; weed infestation for Eleocharis papillosa and slater's skink; and changes in wetlands across their entire range for the painted snipe and freckled duck.
Number of taxa in the Finke Bioregion currently listed as threatened at national and/or Northern Territory level (excluding invertebrates and fish) (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 | 1 | 1 | 1 | 1 |
| birds | 0 | 1 | 0 | 4 |
| mammals | 1 | 4 | 3 | 2 |
There is also some evidence that there is broad scale decline affecting at least some groups of mammals and birds in this bioregion, in addition to those species currently listed as threatened.
Other flora values for eucalypts and acacias
Endemism
- At a national level, there are no eucalypts or acacias endemic to the Finke Bioregion.
Richness
- The subregions of this bioregion support only low to moderate richness of Acacia (13-33 species) and Eucalyptus (1-25 species).
Birds
There have been some changes in the bird fauna in the period between the two bird Atlases. There have been some increases in the abundance and distribution of commensal species from source areas in Alice Springs, most notably the exotic barbary dove and feral populations of the long-billed corella (not otherwise native to this bioregion). There is some evidence for an increase in grassland birds.
Over a longer period than that encompassed by the bird Atlases, there is evidence of broad-scale decline of a number of native species, including Australian bustard and spinifex pigeon, with decline probably reaching regional extinction for the night parrot, grey currawong, bush stone-curlew and slender-billed thornbill.
Mammals
The Finke Bioregion has suffered substantial losses of its mammal fauna. For example, in the Northern Territory portion of the Finke Bioregion of 41 native mammal species recorded, at least 11 are extinct or no longer occur in the bioregion, while several others have suffered population declines.
Management Responses
Reserve consolidation
There are no major reserves in the bioregion. The existing small reserves fall well short of the ideal comprehensive, adequate and representative system. Most vegetation types in the bioregion are unreserved, and the few reserved vegetation types are protected to only a very small extent. The main priorities are for increased reservation of chenopod shrublands (NT vegetation types 108, 109, 110 and 111), coolabah (Eucalyptus microtheca) woodlands (NT vegetation type 27), and Acacia shrublands and woodlands.
Off park conservation for species and ecosystem recovery
Conservation measures for threatened species involve the same set of integrated NRM issues described below: landscape-wide amelioration of the impacts of feral animals, weeds, changed fire regimes and livestock.
Integrated NRM
An NHT-supported resource assessment of the Northern Territory portion of the Finke Bioregion was completed in 2004. This included a comprehensive survey of the bioregion's flora and fauna, an assessment of conservation values and potential threatening processes, and evaluation of options for conservation management. The results of this resource assessment are provided in a report ‘A Resource Assessment Towards a Conservation Strategy for the Finke Bioregion, NT’ prepared by Helen Neave, Catherine Nano, Chris Pavey, Mac Moyses, Bretan Clifford, Jeff Cole, Mark Harris and David Albrecht.
A major recommendation arising from the results of the wildlife survey and the overview of threatening processes is that emphasis move away from conservation of single species, to that which considers impacts of threatening processes on ecosystem functioning and wildlife assemblages across the landscape. Several key habitats have been identified which are in need of conservation action. There are also a number of other habitats of conservation value in the Finke Bioregion such as important wetlands, sites of botanical significance, and fauna ‘hotspots’ (i.e. areas containing a concentration of species of conservation significance).
NRM priorities for the bioregion include the establishment or enhancement of collaborative (cross-tenure) management of feral animals, weeds and fire, the development of off-reserve conservation strategies, and the maintenance of some water-remote (lightly-grazed) habitats, particularly those of conservation significance.
'A Resource Assessment Towards a Conservation Strategy for the Finke Bioregion NT'
Further Information and Gaps
Major data gaps and research priorities for bioregion
Given the existing biodiversity surveys in the NT, the main outstanding research priorities are for additional comprehensive sampling in the SA portion of the bioregion, cross-border integration of data sets and conservation planning, assessment of the responses of biodiversity to threatening processes and their management, and the establishment of monitoring programs for the ongoing assessment of threats, status of native biodiversity, and refinement of management.
Management would also benefit from more detailed environmental mapping, in particular vegetation mapping at the scale of 1:250,000 or better.
