Bonobo apes, primates unique to Congo and humankind's closest relative, groom one another at a sanctuary just outside the capital Kinshasa. Reuters

The bonobo, an endangered species of apes found in the Democratic Republic of the Congo, is rapidly losing its territory to a burgeoning human population that has triggered deforestation and rampant poaching, according to a new study jointly conducted by University of Georgia, University of Maryland, Wildlife Conservation Society, World Wildlife Fund and other groups.

The researchers used data from nest counts and remote-sensing imagery to find that bonobos, which are considered to be one of humankind's closest living relatives, keep away from areas of high human activity and forest fragmentation. As a result, according to the study published in the December edition of Biodiversity and Conservation, only 28 percent of the bonobo's range remains habitable for the apes.

“The results of the study demonstrate that human activities reduce the amount of effective bonobo habitat and will help us identify where to propose future protected areas for this great ape,” Jena R. Hickey of Cornell University and the University of Georgia, and the study's lead author, said in a statement.

The researchers believe that for bonobos to survive over the next 100 years or more, it is vital for humans to understand the apes’ range, their distribution, and the factors that determine their distribution to assist conservation efforts. The researchers added that the current study of suitable bonobo habitat could help identify areas that have not yet been surveyed but could likely support the apes' survival.

"Bonobos are probably the least understood great ape in Africa, so this paper is pivotal in increasing our knowledge and understanding of this beautiful and charismatic animal,” Ashley Vosper of the Wildlife Conservation Society said, in the statement.

The research team compiled data on bonobo nest locations within the lowland forests of the DRC that were collected by numerous organizations between 2003 and 2010. Using the data, the researchers produced more than two thousand "nest blocks” where each block is defined as a 1-hectare area occupied by at least one bonobo nest.

The researchers then tested a set of factors, addressing both ecological conditions and human impact, such as distance from roads, agriculture and forest loss among others, and produced a model that identified and mapped the most important environmental factors contributing to the bonobo's nesting location.

According to researchers, distance from agricultural areas was the most important predictor of bonobo presence. The study also found that only 27.5 percent of habitat suitable for the bonobo is located in existing protected areas.

"Bonobos that live in closer proximity to human activity and to points of human access are more vulnerable to poaching, one of their main threats," Janet Nackoney, a research assistant professor at University of Maryland, said.