Many threats and competing priorities
The Lake Eyre Basin is one of the largest internally draining river systems in the world, comprising one sixth of the Australian continent. It contains many important natural and cultural assets such as Kati Thanda-Lake Eyre, Uluru and Coongie Lakes. The Basin is also home to many unique, rare, threatened species such as the greater bilby, yellow-footed rock wallaby, night parrot, grey falcon and letter-winged kite.
Two of the greatest threats to these native species are climate change and invasive species. The resources available for addressing these threats are limited, so identifying cost-effective strategies can deliver better conservation outcomes overall.
When deciding how to invest efforts and budgets to control invasive species, factoring in future climate change helps to identify the most efficient opportunities for conserving biodiversity.
Assessing the conservation options
For the first time, we have shown how considering climate change impacts over the next 50 years alters decisions on how to mitigate threats to biodiversity today.
We assessed 11 different management strategies for invasive animals, which were drawn from the collective experience and knowledge of 34 experts and stakeholders representing federal, state and local governments, Indigenous landholders, pastoralists, and non-government organisations, and nine members from the Lake Eyre Basin advisory committees (Scientific and Community).
Assisted by models of current distributions of threatened species and their projected distributions under a future climate scenario, these experts estimated costs, feasibilities and benefits for each strategy. This was aimed at improving the persistence of 148 native species listed as threatened, along with additional species considered of concern by experts. We then evaluated the relative cost-effectiveness of each strategy.
Identifying the most cost-effective actions
This work provides a basin-wide picture of the significant flora and fauna most at risk of extinction, and provides a cost-effective approach for selecting invasive animal control strategies in the LEB to best protect them.
The five most cost-effective strategies within the Lake Eyre Basin are the control of pigs, horses and donkeys, cane toads, camels, and rabbits. Combined, these strategies have an estimated average annualised cost of $16 million over 50 years. The most cost-effective strategy is the management of feral pigs, at approximately $2 million (average annualised cost) in specific locations within the Basin.
However, because many of the strategies identified benefit the same species, selecting multiple strategies to implement from the prioritised list may not be the most efficient use of resources. Therefore, we developed a complementarity approach that evaluates strategies at the same time, so that bundles of strategies can be selected to optimise outcomes according to budgets.
We used this approach to recommend bundles of strategies that maximise the number of threatened species potentially secured at a minimum cost.
- Priority threat management of invasive animals to protect biodiversity: Lake Eyre Basin [pdf · 7.8mb] (CSIRO Research Publications Repository)
- Priority threat management of invasive animals to protect biodiversity: Lake Eyre Basin TXT (41 KB)