At 6:00 am in the mountainous rainforests of Hainan,the sun has not yet finished rising over the horizon. However, the environment is already alive with the sounds of indigneous animals including the Hainan Gibbon. A small piece of equipment mounted on one of the trees automatically turns itself on and the calls the members of the gibbon troupe make between each other are beginning to be recorded and real-time transmitted back to a terminal station for permanent storage as part of the important records of the Hainan gibbon sound library.

On November 29, the Hainan National Park Research Institute and the International Union for Conservation of Nature (IUCN) released to the public their phased objectives in the Hainan gibbon acoustic monitoring project. With the goal of establishing a Hainan gibbon sound database and carrying out individual identification research of Hainan gibbons based on acoustic data in the future, the project has already managed to successfully achieve automatic identification and real-time return of acoustic recordings of the island's native gibbon species.

Automatic recognition of gibbon sounds and real-time data transmission from 5 devices

Launched in January 2021 and led by the Hainan National Park Research Institute, the project "currently has 45 traditional acoustic monitoring devices set up for five Hainan gibbon troupes", said Wang Jichao (Project leader, and Hainan Normal University College of Life Sciences vice dean and professor). According to Professor Wang, this Huawei supported project's front end technology is capable of achieving automatic recognition of Hainan gibbon sounds and of making records throughout the year.

Professor Wang explained that acoustic monitoring is being carried out on gibbon troupes C & E with wireless transmission devices based on traditional acoustic monitoring equipment. A qualitative and quantitative leap forward in acoustic monitoring, "once any of the Hainan gibbons make a sound, the equipment will self activate and start recording."

Deciphering vocal cues will be the basis for future identification of individual gibbons

Why engage in a project such as this one? What is the use of recording the sound of Hainan gibbons? These are just a few questions which laymen have for Professor Wang. "Just like human voices, the voices of the Hainan gibbon have vocal characteristics which potentially can be used to identify them. This will be of great use in future research work."

"For our next step, we plan to start full real-time acoustic monitoring of the gibbons' habitat and start building an acoustic database." Professor Wang said that after being collected and organized, the data from this acoustic monitoring can provide a strong basis for all sorts of different kinds of research and conservation work.

Once the voices of the various gibbons have been matched to specific individuals, research can proceed on their linguistic structure.

"In the future, we hope analyzing these sounds will allow us to understand the way Hainan gibbons transmit information to each other, how they feel about their habitat and surroundings, and how they communicate with other organisms." Professor Wang believes that the sounds made by Hainan gibbon are a language which the population uses for communication with each other and that the analysis of acquired acoustic data in combination with behavioral monitoring can be used to study and understand the way Hainan gibbons express emotions such as joy, anger, and sadness.