Saving Biodiversity From Climate Change

Scientist Cassandra Nichols from James Cook University studies the effects of climate change on the Daintree Rainforest at the Australian Canopy Crane Research Station on August 7, 2009 in Cape Tribulation. (Phil Walter/Getty Images)

While politicians debate climate change, scientists are looking at adaptation strategies to the changing climatic conditions. Professor Stephen Williams is one of those scientists. Head of the Centre for Tropical Biodiversity and Climate Change (CTBCC) in Townsville, he is leading the development of scientific techniques to document species at risk from global warming, while identifying likely climate refuges or refugia for those species.

Australia’s Wet Tropics in North Queensland may be one of world’s most vulnerable regions to climate change, Prof Williams told The Epoch Times. He said most of the Wet Tropics vertebrate species (birds, mammals, reptiles and amphibians) are 4-10 million years old and in the past, have survived small amounts of climatic change on cool mountaintops. It is estimated that the area may have been subjected to about 1.5 degrees of warming during past periods, but that it has probably been accompanied by alleviating effects of higher rainfall.

With greater increases in global warming predicted, along with lower rainfall and more extreme events such as droughts, storms and fires, Prof Williams explained the urgency of increasing the resilience of the Wet Tropics. “Now it’s much more fragmented. We’ve got other impacts like feral animals, big cleared areas that it is hard for species to migrate across”, he said.

Mitigation and Adaptation

In 1988, Australia signed the International World Heritage Convention to protect the Wet Tropics and Prof Williams wants to see this commitment followed through. Mitigation and adaptation offer solutions to averting these extinction predictions (See FACT BOX).

Mitigation involves reducing global warming through government policies and individuals taking action to reduce their carbon footprint. Prof Williams said people can lobby their Members of Parliament and governments to let them know how bad these impacts will be and that people care. He acknowledged that attitudes are changing, but commented: “Whether or not it will be fast enough, or enough, is another matter.”

Adaptation refers to the ability of ecosystems to adjust to and cope with climate change. On the ground, the CTBCC is working with the Wet Tropics Management Authority (WTMA) to develop practical management strategies to maximise biodiversity protection and adaptation based on the idea of refugia.

Cool Refugia

The Wet Tropics is a complex area with some places naturally cooler due to shading factors such as topography, density of canopy and cloud cover. The researchers have mapped out these cool refugia, for example, areas shaded by mountains and gorges.

“These refugia are the place to focus your efforts because that’s where you’re going to get the most bang for your buck,” Prof Williams said. Now, WTMA can spend its limited resources on making the refugia more resilient to climate change, for example, through control of weeds, feral animals and impacts from people.

“We can identify those areas that are most valuable from a climate change perspective and also identify areas that might be really good for targeted restoration, again to get your most value for your dollar,” Prof Williams added. Some refugia have been historically cleared, but can now be replanted to re-establish canopy cover. Refugia currently outside the World Heritage Area could be added in or voluntarily protected by people who want to list their property for wildlife conservation.

The information will become increasingly available as downloadable resources for community groups, he said. This will enable restoration and conservation efforts to be targeted in the best places possible and with the best use of resources.

New Directions

The team has also studied physiological responses of various species to increased temperatures and reduced water availability, and their research is evolving. For instance, Prof Williams says it is much more important to understand the effects of the hottest week in summer than average temperature increases, as there have been several severe impacts from heatwaves. He cited decreases in the range of the lemuroid ringtail possum as an example. The intensity and frequency of heatwaves and also (mini) droughts could be very significant factors in species survival, he said.

The Federal Government has taken an interest in CTBCC’s research and is looking at applying it across Australia. Also the World Wildlife Fund International is now focusing on the idea of refugia globally and applying these distribution modelling techniques on a broad scale across many thousands of species.

FACT BOX
Based on current trends, a minimum of three to four degrees warming could occur by 2100 with the following predictions:
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•20-30 per cent of all rainforest vertebrate species would become extinct

•Another 30-40 per cent would be critically endangered

•The remainder should be alright

•But 40-50 per cent of endemics would either be extinct or critically endangered

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The World Heritage Area was established to protect these unique species, mostly highly adapted to the upper mountains, for example lemuroid ringtail possums, golden and toothbill bowerbirds, and some species of frogs.