BY SEAN L. MAXWELL, RICHARD A. FULLER, THOMAS M. BROOKS& JAMES E. M. WATSON - 11 AUGUST 2016 - NATURE
There is a growing tendency for media reports about threats to biodiversity to focus on climate change.
Here we report an analysis of threat information gathered for more than 8,000 species. These data revealed a contrasting picture. We found that by far the biggest drivers of biodiversity decline are overexploitation (the harvesting of species from the wild at rates that cannot be compensated for by reproduction or regrowth) and agriculture (the production of food, fodder, fibre and fuel crops; livestock farming; aquaculture; and the cultivation of trees).
Early next month, representatives from government, industry and non-governmental organizations will define future directions for conservation at the World Conservation Congress of the International Union for Conservation of Nature (IUCN). High on the agenda for political leaders, non-governmental organizations, conservationists and many others will be taking steps to turn the 2015 Paris climate agreement into action. It is also crucial that the World Conservation Congress delegates — and society in general — ensure that efforts to address climate change do not overshadow more immediate priorities for the survival of the world’s flora and fauna.
On the list
Since 2001, the categories and criteria of the IUCN Red List of Threatened Species — a standard for the evaluation of extinction risk — have guided assessments, now for 82,845 species. Assessors assign species to categories, including ‘near-threatened’, ‘vulnerable’, ‘endangered’ or ‘critically endangered’ depending on their population size; past, current and projected population trends; geographic range and other symptoms of extinction risk. Species in the latter three groups are collectively referred to as ‘threatened’.
To assess the relative prevalence of current hazards to biodiversity, we quantified threat information for 8,688 near-threatened or threatened species belonging to species groups in which all known species have been assessed (for complete list of taxa included, see Supplementary Information).
The basic message emerging from these data is that whatever the threat category or species group, overexploitation and agriculture have the greatest current impact on biodiversity (see ‘Big killers’).
Of the species listed as threatened or near-threatened, 72% (6,241) are being overexploited for commerce, recreation or subsistence.
