An update to the International Union for the Conservation of Nature Red List of Threatened Species, which assesses the extinction risk of the world's plants, animals, and fungi, moves a key gorilla subspecies, the Democratic Republic of Congo's Grauer's gorilla, to "critically endangered" status.
Just 3800 Grauer's gorilla remain - a sharp decline in numbers for the world's largest gorilla, and one largely driven by geopolitical upheaval as the Rwandan genocide drove large numbers of refugees into the gorilla's habitat.
The sharp decline of Grauer's gorilla meant that the larger species to which it belongs, the Eastern gorilla - which also includes the Mountain gorilla - was listed as "critically endangered".
The international meeting, which convenes every four years, is the world's largest environmental decision-making forum, bringing together heads of state and other government officials, civilians, indigenous peoples, business leaders, and academics to address the world's biggest conservation challenges.
Over 8000 delegates from 184 countries are in attendance.
The IUCN uses the Red List to classify organisms according to the severity of their extinction risk; in descending order of threat, the categories are "critically endangered," "endangered," "vulnerable,"
"near threatened" and "least concern," The list also includes categories for extinct and data-deficient species. Of the 82,954 species currently assessed, more than a quarter are threatened with extinction.