Climate and land-use changes ‘have caused 18% of habitat loss’

Climate change and changes of land use have caused mammals, birds and amphibians to lose on average 18% of their habitat worldwide since 1700, research indicates.

This could rise to a 23% loss in the next 80 years in a worst-case scenario, according to the Cambridge University study.

The size of an animal’s habitat, by geographical range, is a strong predictor of a species’ vulnerability to extinction.

The study, published in the journal Nature Communications , analysed changes in the geographical range of 16,919 species from 1700 to the present day.

Data was also used to predict future changes up to the year 2100 under 16 different climate and socio-economic scenarios.

The s t u d y ’s first author Dr Robert Beyer, of Cambridge ’s Department of Zoology, said: “The habitat size of almost all known birds, mamma ls and amphibians is shrinking, primarily because of land conversion by humans as we continue to expand our agric ultural and urban areas.”

The amount of habitat loss varies, with 16% of species having already lost more than half of their estimated natural range.

This figure could rise to 26% of species by the end of the century, according to the research.

Species’ geographical ranges were found to have recently shrunk most significantly in tropical areas, where for instance rainforest has been cleared for oil palm plantations in South East Asia and for pasture land in South America.

“The tropics are biodiversity hotspots with lots of small-range species,” said Dr Beyer

“If one hectare of tropical forest is converted to agricultural land, a lot more species lose larger proportions of their home than in places like Europe.”