Prof Guy Midgley from Stellenbosch University is one of 125 specialists from around the world who have contributed to the World Wildlife Fund's (WWF) Living Planet Report 2020, published today.
Prof Midgley, an internationally acknowledged leader in the field of biodiversity and climate change science, heads the Global Change Biology Group in the Department of Botany and Zoology at Stellenbosch University.
The Living Planet Report 2020 presents a comprehensive overview of the state of our natural world through the Living Planet Index. This index, provided by the Zoological Society of London, has been tracking trends in global wildlife abundance since 1970.
According to a media release issued by WWF, the Living Planet Index shows that there has been a 68% decline in global vertebrate species populations between 1970 and 2016, mainly caused by environmental destruction and the use and trade of wildlife.
In the section “Deep dive into biodiversity in a warming world" Prof Midgley writes that even with significant mitigation efforts, “up to one-fifth of wild species are at risk of extinction this century due to climate change alone". Even more concerning is the fact that recent modelling has shown that changing climate conditions could begin breaching the tolerance limits of most species in multi-species communities roughly simultaneously, causing abrupt losses of biodiversity. Midgley adds that biodiversity hotspots around the world, like the Cape Fynbos and Succulent Karoo, could be particularly vulnerable to such effects.
Reducing emissions from fossil fuel use, in particular, is essential to avoid these risks, says Midgley. “Abrupt thresholds could be reached in tropical oceans within a decade under a high-emissions scenario, spreading to tropical forests and reaching higher latitudes by mid-century. Up to 15% of ecological communities would be exposed to this threshold if global warming exceeds 4° C, but fewer than 2% if global warming is kept below 2° C," according to the work referred to in the report. Recent work by a team working on the SPARC program (http://www.sparc-website.org/), in which Midgley co-led work on modelling the vulnerability of African biodiversity to climate change, showed that increasing land available for conservation would substantially reduce climate change extinction risks, regionally and globally.
According to the Living Planet Report 2020, pioneering modelling shows that without further efforts to counteract habitat loss and degradation, global biodiversity will continue to decline. To turn this situation around, we need “bolder, more ambitious conservation efforts" and a transformation in how we produce and consume food". In this regard, the WWF is calling for urgent action to reverse the trend by 2030 by ending the destruction of natural habitats and reforming our food system.
In the Foreword to the report, Marco Lambertini, Director General of WWF International, writes that “a deep cultural and systemic shift is urgently needed, one that so far our civilization has failed to embrace: a transition to a society and economic system that values nature, stops taking it for granted and recognise that we depend on nature more than nature depends on us".