For decades, mountain gorillas have been subjected to uncontrolled hunting, disease, habitat loss and the ravages of human conflict. Their numbers plummeted, and they are now considered endangered. But as George Dvorsky of Gizmodo reports, there is encouraging news for these great primates. A new survey has found that the mountain gorilla population has risen to 1,063 confirmed individuals—still a disconcertingly low number, but a sign that conservation efforts are working.

The population census focused on two areas where mountain gorillas, a subspecies of eastern gorilla, make their home: the Bwindi Impenetrable National Park in Uganda and the contiguous Sarambwe Nature Reserve in the Democratic Republic of Congo. More than 75 trained workers participated in the survey, scouring gorilla habitats for fecal samples. According to John C. Cannon of Mongabay, around 2,000 samples were sent to the the Veterinary Genetics Laboratory at the University of California, Davis, where scientists used DNA analysis to identify individuals and group identities. In total, the team counted 459 mountain gorillas in these regions, up from the 400 individuals that were estimated to exist in a 2011 survey, UC Davis says.

Yet another survey conducted between 2015 and 2016 found 604 mountain gorillas in the Virunga Massif, a chain of eight volcanoes that stretches across Rwanda, Uganda and the Democratic Republic of Congo. Combined with the results of the new population census, that brings the total number of mountain gorillas up to 1,063—a considerable increase from 2008, when the mountain gorilla population numbered just 680.

The new census comes as the latest indication that this fragile primate population is slowly recovering. Last year, the International Union for the Conservation of Nature (IUCN) upgraded mountain gorillas’ status from “critically endangered” to “endangered,” after estimates showed that the species’ numbers had topped 1,000 individuals.

It has taken a mammoth effort on the part of conservationists and local communities to rescue mountain gorillas from the brink of extinction. As Helen Briggs of the BBC reported last year, specially-trained vets care for the animals in the wild and patrols work hard to fend off poachers; park rangers have given their lives to protect gorillas. Carefully managed eco-tourism has also bolstered local economies and encouraged communities to keep mountain gorillas safe.

The results of the recent survey show “what can be accomplished by a cross-border, multipronged, unrelenting effort to protect a species,” says Tara Stoinski, president, CEO and chief scientific officer of the Dian Fossey Gorilla Fund, which assisted in the Bwindi portion of the census. But she notes that mountain gorillas are still in dire need of protection.

Their total population numbers remain low, and habitat loss, poaching, disease and civil unrest continue to pose a threat to the animals, according to Kirsten Gilardi, chief veterinary officer and co-director of the Karen C. Drayer Wildlife Health Center at UC Davis. Snares intended to catch antelopes, but which can also entangle gorillas, represent another risk. Fauna & Flora International, a conservation group that supported the census, reports that survey workers found and destroyed 88 snares, which is roughly the same number discovered during the 2011 survey.

“[The new] survey results are undoubtedly good news, yet mountain gorillas remain threatened with extinction,” says Matt Walpole, senior director of conservation programs at Fauna & Flora International. “We have to remain vigilant against threats and build on the success achieved to date by ensuring resources—including from tourism—are properly directed to mountain gorillas and local communities.”