Dwindling space for Africa's great apes

Sep 26, 2012
Dwindling space for Africa's great apes
Increasing rates of habitat destruction, as well as poaching for bushmeat and the illegal pet trade threaten the long-term survival of great ape populations in Africa. Credit: From top to bottom-Hjalmar Kuehl/WCF/ Jessica Junker

Over the last 30 years, great ape numbers have plummeted across Africa, due to increasing rates of commercial hunting, habitat destruction, and disease. A continent-wide, data-based overview of their habitats is now possible, as the results of surveys from over 60 sites have been combined through the IUCN/SSC A.P.E.S. (Ape Populations, Environments and Surveys) database (http://apes.eva.mpg.de). This information is crucial to inform global policy and donor decisions, and to predict and mitigate current and emerging threats. These threats include habitat destruction, large-scale infrastructure developments, resource exploitation projects, intensifying hunting pressure and impacts of climate change.

The research was carried out by 47 researchers and , who combined over 15,000 field data points on presence localities of , gorillas and bonobos. The result estimated the continent-wide distribution of suitable ape habitat conditions and changes over the past 20 years. Over 200,000 km² of ape habitat have been lost - approximately four soccer fields every day. This, however, varied dramatically among species, where more than 50% of eastern gorilla habitat appears to have become unsuitable over the years, compared with only about 10% or less for chimpanzee habitat. This, the authors say, may be due to differences in ecological requirements, such as dietary preferences, as well as differences in vulnerability to hunting related to the behaviour and social structure of the different species.

The regions that experienced the greatest conversion of suitable ape habitat were the Congo Basin rainforest and the West African coastal forest in Liberia. Importantly, the lack of decline in other areas may reflect the fact that much habitat had already been lost before the 1990s, such as in the East and West African regions. Even more concerning is the finding that suitable appears to have been particularly severe in the central block - currently regarded as the remaining stronghold of great apes. Even these vast and once-remote forest tracts have been interlaced with logging and mining roads and subsequent human immigration.

"This study shows how threats to African great apes are increasing over time throughout their range. It highlights the urgent need to intensify conservation measures, including law enforcement and raising awareness. Increased and sustained commitment of all stakeholders - local and international - to conservation efforts throughout the range of African great apes is essential to their survival" says Inaoyom Imong of the Wildlife Conservation Society in Nigeria and PhD student at the Primatology Department of the Max-Planck Institute for Evolutionary Anthropology (MPI-EVA).

"This is the first continent-wide estimate of African distribution and its changes over time", says Jessica Junker, also a PhD student at MPI-EVA and lead author of the study. "This is also the first study to have combined data across 22 African ape range countries in an attempt to bridge the gap between local efforts in the field and global ape distribution patterns. We hope that together with a series of other geo-referenced data on human activities, land-cover, topography, and conservation, our model will aid funding agencies, industry and politicians in making decisions in identifying priority conservation areas, research gaps, potential wildlife corridors and future survey sites."

"Once again, a multi-site analysis has demonstrated the increasingly grave situation in which the African great apes exist" says Fiona Maisels, of the Wildlife Conservation Society. "The threats to these species are rapidly increasing: bushmeat hunting continues to expand and the rate of conversion from forest to oil palm plantations and other monocultures is about to explode. Immediate attention is required to ensure that national and regional land use planning integrates wildlife conservation at the very beginning, and law enforcement is of the essence to maintain and protect great apes and their habitats for the future"

Explore further: Half-tonne of smuggled ivory seized in Saudi

More information: Jessica Junker, et al., Recent decline in suitable environmental conditions for African great apes. Diversity and Distributions. Published online on September 23, 2012; DOI: 10.1111/ddi.12005

add to favorites email to friend print save as pdf

Related Stories

Not enough hours in the day for endangered apes

Jul 22, 2010

A study on the effect of global warming on African ape survival suggests that a warming climate may cause apes to run 'out of time'. The research, published today in Journal of Biogeography, reveals that rising temperatures and ch ...

Law enforcement vital for great ape survival

Dec 08, 2011

Recent studies show that the populations of African great apes are rapidly decreasing. Many areas where apes occur are scarcely managed and weakly protected. Researchers from the Max Planck Institute for Evolutionary ...

African nations commit to saving chimps

Jun 21, 2010

The nations of East and Central Africa have developed a 10-year action plan to save one of humankind's closest relatives—the eastern chimpanzee—from hunting, habitat loss, disease, and other threats, according ...

New national park protects world's rarest gorilla

Nov 26, 2008

The Wildlife Conservation Society, the Government of Cameroon, and other partners have collaborated to create a new national park to help protect the world's most endangered great ape: the Cross River gorilla.

World's most endangered gorilla fights back

Dec 05, 2007

In the wake of a study that documented for the first time the use of weaponry by Cross River gorillas to ward off threats by humans, the Wildlife Conservation Society announced today new field surveys to better protect this ...

Recommended for you

UN biodiversity meet commits to double funding

Oct 17, 2014

A UN conference on preserving the earth's dwindling resources wrapped up Friday with governments making a firm commitment to double biodiversity aid to developing countries by 2015.

Climate change alters cast of winter birds

Oct 17, 2014

Over the past two decades, the resident communities of birds that attend eastern North America's backyard bird feeders in winter have quietly been remade, most likely as a result of a warming climate.

New data about marsh harrier distribution in Europe

Oct 17, 2014

The use of ringing recoveries —a conventional method used to study bird migration— in combination with more modern techniques such as species distribution modelling and stable isotope analysis helps to ...

User comments : 0