Climate change threatens the future of rain forest ringtail possums by 2050
Diversity and Distributions
Ringtail possums in the Australian Wet Tropics are collapsing, and extreme heatwaves are the main driver. We built a hierarchical population model on 30 years of survey data, from 1992 to 2021. The model separates real population change from imperfect detection, so a trend is never an artefact of who searched where. It shows that warming, and heatwaves in particular, drove a rapid and severe decline over three decades.
We then ran the fitted model forward. Under forecast warming, populations fall below viability thresholds by 2050. We used the result to nominate the lemuroid ringtail possum for listing under the Environment Protection and Biodiversity Conservation Act. The story reached 70 national news outlets.
Original abstract as published
Aim
The increasing frequency and intensity of extreme weather escalate the pressure of global warming on biodiversity. Globally, synergistic effects of multiple components of climate change have driven local extinctions and community collapses, raising concern about the irreversible deterioration of ecosystems. Here, we disentangle the pressure of increasing warming and frequency of extreme heatwaves on the population dynamics of tropical ringtail possums (family: Pseudocheiridae).
Location
The Australian Wet Tropics World Heritage Area.
Method
Ringtail possums’ population dynamics were estimated between 1992 and 2021 using a hierarchical population model that explicitly described the state process and accounted for imperfect detection. Under our model, we propagated the estimated mechanisms governing the system by forecasting ringtails’ population dynamics between 2022 and 2050. Derived from this process, we calculated the probability of absolute and quasi-extinction using different population viability thresholds.
Results
We find a strong negative effect of climate change on population dynamics, particularly extreme heatwaves, resulting in a rapid and severe decline in ringtails’ population size in the last three decades.
Main Conclusions
Forecasted increases in temperature and heatwaves threaten the collapse of rain forest ringtail possums by 2050, with populations falling below viability thresholds within three decades.
de la Fuente, A. & Williams, S. (2023). "Climate change threatens the future of rain forest ringtail possums by 2050." Diversity and Distributions. 29(1), 173-183.
Possums threatened by climate change · James Cook University media release
70 national stories · Mediaportal coverage report
Global warming drives Wet Tropics possum species from their mountain homes · ABC News
Climate change drives possums from high altitude homes in Queensland's wet tropics · ABC News interview
Tropical Rainforest Research in Education · Skyrail Rainforest Foundation
Project page: Ringtail possum viability forecast