By Dr John Kanowski, Chief Science Officer, and Dr Michael Smith, South-west Regional Ecologist
As a conservation organisation, Australian Wildlife Conservancy’s mission is to protect Australia’s wildlife and their habitats. We do this by acquiring land and managing threats with a focus on wildfire, feral animals and weeds. Where a property has experienced environmental degradation, we aim to restore plant and animal assemblages and long-standing ecological processes, such as the fire regime.
The word ‘conserve’ comes from the Latin ‘to keep’, but what do we do when the fundamental ecological drivers associated with ecosystems and species on a property themselves undergo change? This is the challenging issue we face as climate change exerts its influence on the species and places for which we are responsible.
Although the scientific basis for climate change has been largely established for decades, societal acceptance of the importance of the issue and the urgency for action has been delayed. As a result, emissions of greenhouse gases have continued to increase, making it likely that average global temperatures will rise 1.5 degrees Celsius above pre-industrial levels by as early as 2025 (World Meteorological Organisation, United in Science report). Ongoing changes in temperature, rainfall and evaporation will fundamentally alter the suitability of ecosystems for component species. More dramatically, changes in average conditions greatly increase the likelihood of extreme events, such as the drought and heatwaves that contributed to the 2019-20 wildfires in south-eastern Australia, with severe consequences for conservation.
Modelling impacts of climate change in south-west Western Australia
AWC manages four properties in south-west Western Australia: Karakamia, Paruna, Mt Gibson and Faure Island. The region is one of the most sensitive in Australia to climate change. Over the last century, average temperatures have increased by one degree Celsius, rainfall decreased by up to 20 per cent and streamflow dropped by 85 per cent in the region (Climate trends in Western Australia, WA Department of Primary Industries and Regional Development).
Rainfall zones have moved towards the coast; inland areas have become progressively drier (see map on page 11). These trends are predicted to accelerate in coming decades.
As rainfall and temperature are fundamental aspects of habitat, we can expect these changes to reduce the suitability of south-west Western Australia for species that prefer mesic (wetter and cooler) conditions, while favouring arid-adapted species. As many species are endemic to the mesic south-west, the net result is a predicted decline in species richness. For example, the maps on page 10 show habitat suitability for threatened mammals is predicted to contract to the far south-west of the region by 2070. Mesic-adapted species such as Gilbert’s Potoroo are predicted to lose all their current habitat in a future climate.
What can AWC do to respond to climate change?
AWC scientists are increasingly aware that we need to develop a robust climate change strategy to meet the challenges of conservation in the 21st century. While we have just started on this journey, we envisage the strategy will consider the following issues:
What are we doing now?
While we work on developing our strategy, we can still implement the conservation actions we know will help our native wildlife, such as good fire management and feral animal and weed control. These actions help build populations, maintain genetic diversity and, hence, adaptive potential in our native species. However, whether this will be enough is unknown; for some species, the environmental conditions in their current location may simply become uninhabitable under climate change. In these cases, translocation of species to a cooler or wetter climate may be required.
As a national leader in reintroductions, AWC is well placed to undertake translocation projects and provide advice to others in the conservation community, as this need arises. AWC is also a national leader in the implementation of ecological monitoring on our conservation estate, with our Ecohealth program tracking the status and trends of key conservation assets and threats on our properties.
As climate change starts to bite, ecological monitoring will become increasingly important, providing information on how species are tracking in response to changed conditions, and early warning to managers on when to act.
Doing our bit
Recently, AWC’s Science Coordinator, Dr Fay Lewis, worked with Chief Finance Officer, Andre van Boheemen, to audit our carbon footprint. In summary, we estimate that AWC activities generate 2,000 tonnes CO2-e per annum, predominantly due to transport. However, the fire programs we implement across northern Australia conservatively abate 100,000 tonnes CO2-e per annum through the reduction in wildfire. Additional sequestration is achieved through revegetation programs on Karakamia, Paruna and Dakalanta, and additional abatement through the removal of feral herbivores from large parts of our estate. Based on this analysis, AWC programs make a substantial direct contribution to mitigating climate change.
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