The Critically Endangered Hainan gibbon Nomascus hainanus is the rarest ape and possibly rarest mammal species, comprising a single population of c. 25 individuals in Bawangling National Nature Reserve, Hainan, China. The species occurred historically across Hainan, with an estimated population of c. 2,000 in the 1950s, but experienced a precipitous decline during the 20th century driven by hunting and extensive habitat loss. Periodic surveys since 2003 have failed to locate any individuals outside the Reserve, and there are no captive populations.

Research over the past 3 decades has clarified key aspects of Hainan gibbon biology, behaviour and ecology, and conservation legislation is in place to protect the last population: Bawangling was gazetted as a protected area in 1980 and the species was designated a State 1 Protected Species under the 1988 Chinese Wildlife Protection Law. The first Conservation Action Plan for the species was produced in 2005, focusing primarily on threat abatement. Subsequent management activities have included efforts to protect and restore gibbon habitat, and there has been some apparent growth in the gibbon population. However, the tiny size of the sole population threatens the long-term survival of the species.

To promote effective conservation of the Hainan gibbon a conservation planning workshop was held during 18–20 March 2014 in Bo'ao, Hainan. This international workshop was organized by the Zoological Society of London in cooperation with the Hainan Bawangling National Nature Reserve Management Office and the IUCN Species Survival Commission China Primate Specialist Group, with support from Kadoorie Farm & Botanic Garden and Fauna & Flora International, and was facilitated by the IUCN Species Survival Commission Conservation Breeding Specialist Group. Financial support was provided by the Arcus Foundation and the Mohamed bin Zayed Species Conservation Fund. Over 100 stakeholders participated, including experts in gibbon conservation and small population recovery programmes, and representatives from government, universities, conservation NGOs, zoos, rescue centres and local communities. Following a series of presentations on gibbon status and genetics, conservation activities and viability concerns, participants identified potential threats, challenges and issues considered likely to affect Hainan gibbon population viability and conservation. Working groups discussed the main threats and developed conservation goals, along with recommendations for management and research actions to help achieve the goals. Recommended actions were evaluated for potential benefit, costs, risks and likelihood of success, and timelines, responsible parties/collaborators, resources required, and priority status were assessed where possible for each action.

The newly published bilingual International Conservation Planning Workshop for the Hainan Gibbon: Final Report (available from http://www.cbsg.org and http://www.zsl.org) details the 12 goals and 44 specific conservation actions. Key goals include: effective protection and enhancement of gibbon habitat and connectivity at Bawangling National Nature Reserve; expansion of gibbons into additional good-quality habitat; enhanced monitoring and improved understanding of factors affecting dispersal, group formation and colonization of new habitat; development of an emergency response plan for any future crisis; and improved communication to facilitate collaboration among stakeholders.

The report is being used as a guide to develop both a Chinese Species Conservation Action Plan and an IUCN Species Action Plan. Local and regional management teams are now working with Chinese and international collaborators to conduct activities considered beneficial for the long-term survival of the species. However, additional governmental and international support will be needed to implement all identified priority actions and thus safeguard the future of this rare, endemic Chinese primate.