Western lowland gorillas (Gorilla gorilla gorilla) are more common than previously thought, according to a census of the northern regions of the Republic of the Congo. Led by the New-York-based Wildlife Conservation Society (WCS), the count found 125,000 of the apes in a 47,000-square-kilometre area. Previous estimates held that there were fewer than 100,000 western lowland gorillas in the entire world, and the International Union for Conservation of Nature has speculated that the Ebola virus could have reduced numbers even further.

Credit: T. BREUER/WILDLIFE CONSERVATION SOCIETY/MPI EVOL. ANTHROPOL.

Census-takers counted the gorillas' sleeping nests. The WCS attributes the high numbers to successful management of protected areas in the Republic of the Congo, a food-rich habitat and the “remoteness and inaccessibility” of the region. The work was presented at the International Primatological Society Congress in Edinburgh, UK.

Even so, a separate global assessment presented at the same conference reports that half of primate species are threatened with extinction in the next ten years.