Study Predicts African Great Apes Will Lose 94% of Their Territory 

July 8, 2021 CATALYST Team

A new study about the effects of climate change, land use and human population growth on African great apes found that they may lose up to 94% of their habitat by 2050.

A mountain gorilla in Uganda. Rod Waddington. CC BY-SA 2.0

Great apes are humanity’s closest relatives. They are also a highly endangered group of animals, and experts believe that this status will likely worsen in the coming years. A new study published in the journal Diversity and Distributions predicts that the combined pressures of climate change, human land use and human population growth will lead to immense territory losses for African great apes in the next 30 years.

There are four types of great apes: gorillas, bonobos, orangutans, and chimpanzees. Africa is home to a number of species of great apes, including Cross River and Eastern and Western gorillas, as well as bonobos and chimpanzees. The situation for these species is already critical. All are listed as either endangered or critically endangered on the International Union for Conservation of Nature and Natural Resources Red List of Threatened Species, a comprehensive list detailing the conservation status of animals around the world. And, as wild areas are destroyed for timber, minerals and food; the human population expands; and climate change alters the land where great apes can comfortably live, experts warn that African great apes could lose a devastating portion of their range by 2050.

The study was conducted by nearly 60 scientists from different research institutions, universities and conservation organizations. The scientists used data about African great ape populations from the IUCN database and then modelled the future effects of climate change, land use and human population growth. Using this data, the scientists analysed a best case scenario, where action is taken to protect the environment , and a worst case scenario where nothing is done. There is little difference in the two outcomes. Both result in massive range loss for African great apes, with 85% range loss by 2050 in the “best case” scenario and 94% by 2050 in the “worst case”.

Half of this lost range will be territory inside national parks and other protected areas, the study predicts. Although these areas are safe from human land use, they will still be affected by climate change, which will make the habitat unsuitable for great apes. Most great ape species prefer to live in lowland habitats, but climate change will make them hotter and drier. In areas where there is no higher lands, apes will be left with nowhere to live. In areas where there are uplands, however, experts suggest that great apes will attempt to migrate upward, following the climate and vegetation they prefer.

Yet, even apes that have the ability to migrate as their range decreases may not have enough time to do so. Apes reproduce slowly, have a low population density and require a very specific diet. All of these factors mean that apes are generally not efficient migrators compared to other species; to fully acclimate to a new habitat would take great ape species longer than the 30 years the study predicts they have left.

The authors of the study urge that their findings be used to guide conservation efforts for African great apes in order to prevent irreversible population losses. Their findings suggest that the range loss can be mitigated through specific conservation efforts that focus on new and existing protected areas, as well as connecting habitats that are predicted to still be suitable for great apes in the future.