Climate change and global food demand could drive a startling loss of up to 23 per cent of all-natural habitat ranges in the next 80 years, according to new findings published in Nature Communications. Mammals, birds and amphibians worldwide have lost on average 18% of their natural habitat range as a result of changes in land use and climate change, a new study has found. In a worst-case scenario, this loss could increase to 23% over the next 80 years.
Global food demand currently fuels agricultural sectors to increase land use, moving into habitats previously untouched. What results — deforestation — leaves more carbon dioxide in the air, increasing greenhouse gas emissions, the main driver of climate change. In the U.S. alone, agriculture-related emissions measure 11.6 per cent of the world’s greenhouse gas emissions, which include carbon dioxide, methane and nitrous oxide. “The habitat size of almost all known birds, mammals and amphibians is shrinking, primarily because of land conversion by humans as we continue to expand our agricultural and urban areas,” said Dr Robert Beyer in the University of Cambridge’s Department of Zoology, first author of the report. As a result of climate change, not only will the habitat cover dwindle, but overall habitats may shift altogether. The study forecasts that rising temperatures and changing rainfall patterns have the potential to alter habitats significantly. The Amazon rainforest in South America, for example, is expected to transform from a canopy rainforest to a savannah-like mix of woodland and open grassland in the next 100 years.
“Species in the Amazon have adapted to living in a tropical rainforest. If climate change causes this ecosystem to change, many of those species won’t be able to survive—or they will at least be pushed into smaller areas of remaining rainforest,” said Beyer. While the study quantifies the drastic consequences for species’ ranges if global land use and climate change are left unchecked — it also demonstrates the potential of timely and concerted policy action for halting, or even reversing, the effects of climate change. “Whether these past trends in habitat range losses will reverse, continue, or accelerate will depend on future global carbon emissions and societal choices in the coming years and decades,” said Andrea Manica, who is also a lead author of the study.
