Newhaven Sanctuary - Conservation Programs
Newhaven Sanctuary
In June 2006, the Australian Wildlife Conservancy and Birds Australia entered a partnership to consolidate the management of Newhaven. Responsibility for its management rests with AWC, but Birds Australia will continue to assist, especially with the design and implementation of bird conservation programs.
Newhaven occupies over 2,620 square kilometres, and is large enough to support viable populations of species that are threatened elsewhere. The same expansiveness that offers opportunities for large scale conservation poses significant challenges. Frequent uncontrolled fires have altered ecosystems over much of central Australia. This, coupled with the impact of feral animals, has led to an alarming decline in many once common species.
AWC is engaged in an active management program to restore appropriate fire regimes and limit the depredations of feral animals to deliver a measurable improvement in the health of the landscape and the populations of vulnerable species such as the Mulgara.
Biodiversity surveys and monitoring
Apart from an alarming scarcity of native animals that were once common in central Australia, surprisingly little is known of the specific habitat preferences and interactions of many native species. AWC is compiling a comprehensive biodiversity assessment of Newhaven, augmented by an array of permanent monitoring sites in each of the key ecosystems. These efforts are designed to provide information on the distribution and interdependence of native species and to measure the effectiveness of management over time.
Feral animal control
Feral camels, cats and foxes have all caused significant damage to ecosystem functioning throughout central Australia. At Newhaven, AWC is continuing to control camels, with several hundred removed in the first year of operations. A monitoring program, designed to determine the suppression of cats and foxes by dingoes, is being conducted on Newhaven to allow fine tuning of a control program.
Fire management
Many central Australian plants lay almost dormant for much of their life with significant growth occurring only after the sporadic rain events. Periods of vigorous growth can be more than ten years apart. Long dry periods following this growth make arid zone ecosystems particularly susceptible to fire. The fuel that accumulated in growth periods remains flammable for decades, and fires lit in hot windy periods will burn fiercely for hundreds of kilometres. Significant regrowth after such fires must await the next rain, which could be many years away.
Aboriginal people used fire frequently and extensively, creating a pattern of burned areas that denied fuel to wildfires, while at the same time ensuring that patches of the country remained unburnt for long periods, thus providing a diversity of habitats. Since pastoral development and contraction of Aboriginal people to settlements, large and contiguous areas of central Australia have remained without fire for long periods, only to be eventually burnt by large, severe and destructive wildfires.
AWC is working to re-establish an appropriate fire regime on Newhaven, using a combination of graded fire breaks and patch burning. Graded breaks allow quick access for fire units to control the extent of unplanned fires in remote parts of the property. Graded breaks are also being used to physically divide important habitat areas so that if fire takes hold in part of the habitat, the likelihood of the entire habitat burning at one time is reduced. Patch burning conducted during the cool winter months is used to reduce the continuity of fuel and produce a patchwork of habitats based on time-since-fire. As more of the reserve is managed in this way, the need for graded fire breaks will be reduced.
Weed control
Newhaven has relatively few weeds. However, it has well established populations of central Australia’s two most important environmental weeds, namely Buffel Grass (Cenchrus ciliaris) and Couch Grass (Cynodon dactylon). These species have the potential to become serious pests and are under active control.
Small populations of rubber bush (Calatropis procera) and Paddy’s Lucern (Sida rhombifolia) also occur on Newhaven. These two species are declared noxious weeds (class B) under the Northern Territory’s Weeds Act.
Buffel Grass (Cenchrus ciliaris) was introduced for pasture and has since spread extensively. This species can withstand long periods of drought and frequent fires. It inhibits germination of native species, reducing biodiversity, and “infills” between Spinifex clumps, thus encouraging the spread of fire and increasing its intensity. AWC is mapping the extent of Buffel Grass infestations and applying herbicide in key areas after rain events, since this is the only time that the plants are susceptible.
Couch Grass (Cynodon dactylon) is more water dependant and is established around bores. Like buffel grass it is favoured by fire and increases fuel loads. This species is capable of smothering native plant species, thereby having a devastating effect on species diversity and food availability for animals. Couch Grass will happily grow in or near areas that naturally or artificially retain higher moister levels and in semi-saline areas. It has the potential to spread to the fringes of claypan and saltlake areas where it will displace important natives such as Yalka (Cyperus bulbosus), which produces small underground bulbs. These bulbs are an important food source for mammals such as the Bilby (Macrotis lagotis) and the Spinifex Hopping-mouse (Notomys alexis).
AWC is preventing the free flow of water from bores and applying herbicide to this weed to prevent its spread. The long-term aim of weed management at Newhaven is to eradicate these two species from the reserve.