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Leavesley A.J.,Australian National University | Leavesley A.J.,Bushfire Cooperative Research Center | Leavesley A.J.,Desert Knowledge Cooperative Research Center | Cary G.J.,Australian National University | Cary G.J.,Bushfire Cooperative Research Center
Pacific Conservation Biology | Year: 2013

It is often assumed that a fine-scaled mosaic of different times-since-fire supports greater biodiversity than a coarsescaled mosaic - the fire mosaic hypothesis. A potential mechanism of the fire mosaic hypothesis is the effect of area on species diversity. We investigated the effect of patch area on bird communities in mulga (Acacia aneura) woodland in central Australia. The study was conducted at Uluru Kata-Tjuta National Park using 55 fixed-area sites classified to the time since last fire: burnt 2002; burnt 1976 and long unburnt. Birds were surveyed in the winter and spring of 2005 and 2006. Of 20 key species, two showed a positive density-area effect (i.e. higher density in larger patches). Patch area did not affect total bird density or species richness. However, species turnover (ß-diversity) was greater in large patches in the burnt 2002 treatment than it was in small patches. There was no effect of patch area on the composition of the bird communities in any of the time-since-fire classes. We concluded that patch area did affect the distribution of some birds in mulga woodland. However, patch area was not a mechanism of the fire mosaic hypothesis because the effects of patch size tended to increase avian diversity in larger patches rather than small.

O'Loingsigh T.,Monash University | McTainsh G.H.,Griffith University | McTainsh G.H.,Desert Knowledge Cooperative Research Center | Tapper N.J.,Monash University | Shinkfield P.,National Climate Center
Aeolian Research | Year: 2010

Weather stations around the world record surface meteorological observations using the SYNOP coding system defined by the World Meteorological Organization (WMO). These codes are used for a variety of meteorological studies, along with remote sensing and modelling studies of wind erosion and dust transport. Despite the widespread use of SYNOP codes in wind erosion research and monitoring in Australia and internationally, few studies, if any, have examined in detail the manner in which the codes are recorded and archived, and how this might affect the quality of the data and the outcomes of the research. In this study we investigate how different methods of recording and archiving SYNOP codes relating to wind erosion and dust transport can under-estimate the frequency and inaccurately record the timing of wind erosion events. We examine 8 years of wind erosion data in the Lake Eyre Basin of central Australia (2000-2008) using more complete data from weather stations and compare them with the official archived dataset. On average, the number of dust days in the Lake Eyre Basin was under-estimated by 7% per year and the number of dust storm days (visibility <1 km) by 15% per year. In addition, what appears to be a clear inverse relationship between rainfall and dust activity may in some cases be an artefact of dust codes having been lost in processing and archiving. We also found that thunderstorms are responsible for more dust storms than previously thought. © 2010 Elsevier B.V. All rights reserved.

Vaarzon-Morel P.,Desert Knowledge Cooperative Research Center
Rangeland Journal | Year: 2010

This paper reports on a survey of Aboriginal perceptions of feral camels undertaken with Aboriginal people from 27 Aboriginal communities within the current feral camel range in central Australia. Research methods were qualitative, involving face-to-face semi-structured interviews. Views were sought on feral camel presence and impacts and people's attitudes towards feral camel management. In just over two-thirds of the communities surveyed, interviewees reported seeing camels. Many interviewees in high camel density areas claimed that camels damage natural and cultural resources (such as water places and bush tucker) and affect their customary use of country. Roughly a third of interviewees also claimed that feral camels deprive native species of water. Damage to infrastructure and homelands was also reported, and concern was expressed over the danger that camels posed both on and off the roads. At the same time, camels are said to have positive benefits and most interviewees view them as a potential resource. Yet despite a widely held view among interviewees that camels need to be controlled, the majority were only prepared to consider limited management options. What is significant, however, is that Aboriginal views on feral camels today are not homogenous: there is a diversity of perspectives emerging in response to transformations being brought about by feral camels on Aboriginal land. The findings are discussed in the context of earlier studies on Aboriginal perceptions of feral animals in central Australia, which concluded that feral animals were thought not to be a significant land management problem but to 'belong to country'. The implications of changing Aboriginal perceptions of feral camels are discussed for the development of a collaborative feral camel management strategy. © Australian Rangeland Society 2010.

Leavesley A.J.,Australian National University | Leavesley A.J.,Bushfire Cooperative Research Center | Leavesley A.J.,Desert Knowledge Cooperative Research Center | Cary G.J.,Australian National University | And 4 more authors.
International Journal of Wildland Fire | Year: 2010

The principal ecosystem driver in arid Australia is unpredictable rainfall, but it is hypothesised that fire also plays an important role in determining the distribution of animals. We investigated the effect of fire on birds in mulga (Acacia aneura) woodland in the central Australian arid zone. The study was conducted at UluruKata Tjuta National Park using 63 sites classified into one of three time-since-fire classes: burnt 2002; burnt 1976; and long-unburnt. Birds were sampled in the winter and spring of 2005 and 2006 and vegetation structure was measured at all sites. Vegetation structure varied with time-since-fire. The burnt 2002 treatment was an early seral stage of mulga woodland and effectively a grassland. The burnt 1976 and long-unburnt treatments were both woodland, but the long-unburnt treatment had greater canopy cover and height. The bird community in the burnt 2002 treatment was characterised by granivores, whereas that in the burnt 1976 and long-unburnt treatments was characterised by foliar insectivores. All species showed monotonic responses to time-since-fire (i.e. none were at significantly highest density in the burnt 1976 treatment). Fire in mulga woodland changed the vegetation structure and consequently also changed the composition of the bird communities. © 2010 IAWF.

King K.J.,Australian National University | King K.J.,Bushfire Cooperative Research Center | Cary G.J.,Australian National University | Cary G.J.,Bushfire Cooperative Research Center | And 5 more authors.
Global Change Biology | Year: 2013

This study explores effects of climate change and fuel management on unplanned fire activity in ecosystems representing contrasting extremes of the moisture availability spectrum (mesic and arid). Simulation modelling examined unplanned fire activity (fire incidence and area burned, and the area burned by large fires) for alternate climate scenarios and prescribed burning levels in: (i) a cool, moist temperate forest and wet moorland ecosystem in south-west Tasmania (mesic); and (ii) a spinifex and mulga ecosystem in central Australia (arid). Contemporary fire activity in these case study systems is limited, respectively, by fuel availability and fuel amount. For future climates, unplanned fire incidence and area burned increased in the mesic landscape, but decreased in the arid landscape in accordance with predictions based on these limiting factors. Area burned by large fires (greater than the 95th percentile of historical, unplanned fire size) increased with future climates in the mesic landscape. Simulated prescribed burning was more effective in reducing unplanned fire activity in the mesic landscape. However, the inhibitory effects of prescribed burning are predicted to be outweighed by climate change in the mesic landscape, whereas in the arid landscape prescribed burning reinforced a predicted decline in fire under climate change. The potentially contrasting direction of future changes to fire will have fundamentally different consequences for biodiversity in these contrasting ecosystems, and these will need to be accommodated through contrasting, innovative management solutions. © 2012 Blackwell Publishing Ltd.

McAllister R.R.J.,Desert Knowledge Cooperative Research Center | McAllister R.R.J.,CSIRO | Holcombe S.,Desert Knowledge Cooperative Research Center | Holcombe S.,Australian National University | And 16 more authors.
Journal of Arid Environments | Year: 2011

Social actors in arid regions must develop strategies to respond to available resources, which are scarce, variable, patchy and unpredictable relative to other regions. We explore our observations of relationships amongst people and organisations in Australian deserts using a stylised network model of the structure of social networks in arid systems. Results suggest that temporal resource variability drives increased network density, but with fewer strong ties; sparse populations drive a relatively higher proportion of strong ties, and that networks develop a hub configuration as resource endowments become more patchy spatially. These ideas highlight some issues that warrant improved understanding by actors seeking to enhance livelihoods and local resilience in these extreme environments. © 2010.

McAllister R.R.J.,CSIRO | McAllister R.R.J.,Desert Knowledge Cooperative Research Center
Rangeland Journal | Year: 2012

Livestock mobility is practised by pastoralists to cope with some of the variability and unpredictability of limited forage resources and because a diverse portfolio of strategies is needed to manage risk. The global trend towards rangeland privatisation, fragmentation and land-use intensification is eroding many of the institutions that have traditionally facilitated pastoral mobility. While Australia's pastoral industry was developed as a European private-property system, livestock mobility has recently been increasing, indicating an important response to variability regardless of a nation's wealth or development. This paper discusses how opportunistic movements of livestock over large scales by trading grazing rights between enterprises are effective but imperfect. Knowledge about the trustworthiness of individuals and local environments is often limited and poorly monitored. There is scope for policy to support mobility by targeting these institutional failures. The Australian system of trading grazing rights can inform efforts to maintain spatial flexibility in the industrial era. © Australian Rangeland Society 2012.

Vaarzon-Morel P.,Desert Knowledge Cooperative Research Center
Rangeland Journal | Year: 2010

Feral camels have significant negative impacts on the environment and the social/cultural values of Aboriginal people. These impacts include damage to vegetation through feeding behaviour and trampling; suppression of recruitment in some plant species; damage to wetlands through fouling, trampling, and sedimentation; competition with native animals for food, water and shelter; damage to sites such as waterholes, that have cultural significance to Aboriginal people; destruction of bushfood resources; reduction in Aboriginal people's enjoyment of natural areas; creation of dangerous driving conditions; damage to people and vehicles due to collisions, and being a general nuisance in remote settlements. Negative economic impacts of feral camels mainly include direct control and management costs, impacts on livestock production through camels competing with stock for food and other resources and damage to production-related infrastructure. The annual net impact cost of feral camels was estimated to be $10.67million for those elements that could be evaluated according to market values. We established a positive density/damage relationship for camels and infrastructure on pastoral properties, which is likely to hold true for environmental variables and cultural/social variables as well. Therefore, irrespective of climate change, the magnitude of the negative impacts of feral camels will undoubtedly increase if the population is allowed to continue to increase. Furthermore, the likelihood that camels would be epidemiologically involved in the spread of exotic diseases like bluetongue and surra (were there to be outbreaks of these diseases in Australia) is also very likely to increase with population density. On the basis of our present understanding, we recommend that feral camels be managed to a long-term target density of 0.10.2camels/km 2 at property to regional scales (areas in the order of 10000100000km 2) in order to mitigate broad-scale negative impacts on the environmental, social/cultural and production assets of the Australian rangelands. © Australian Rangeland Society 2010.

Lamb D.S.,Charles Darwin University | McGregor M.J.,Desert Knowledge Cooperative Research Center | McGregor M.J.,Curtin University Australia | Vaarzon-Morel P.,Desert Knowledge Cooperative Research Center
Rangeland Journal | Year: 2010

Feral camels have severe negative impacts on key environmental economic and social/cultural assets across a wide area in Australia and their population is increasing. In this paper we utilised Multicriteria Evaluation (MCE) within a Geographic Information System (GIS) to create a decision tool for their management. Six management methods which are currently used for managing feral camels and their impacts: aerial culling, ground culling, exclusion fencing, and commercial extraction for live export, pet meat, or human consumption, were considered in the development of the tool. The decision tool used GIS-based MCE to determine the suitability of each of the management methods across the range of feral camels in Australia. A range of method-dependent criteria and factors served as inputs to the GIS-based MCE, which produced a suitability map or surface for each of the management methods. The broad-scale nature, Australia wide, of the work resulted in the suitability maps generated being of limited value in identifying fine-scale priority locations for management. The suitability maps did serve to identify broad-scale, cross-jurisdictional management zones where one or more of the management methods may be applicable. Geographic Information System-based MCE was concluded to have the potential to identify the appropriate areas for the application of specific feral camel management methods. Four management zones were then defined within the area of Australia in which feral camels are present. © Australian Rangeland Society 2010.

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