SCIENCE

Gorillas may be far more numerous than previously thought, but they’re still critically endangered and numbers are falling fast. (The Guardian)

Use our lesson to understand how abiotic factors, vegetation zones, and human activity contribute to the distribution of gorilla populations.

Teachers, scroll down for a quick list of key resources in our Teachers Toolkit.

Discussion Ideas

• Why was the new research able to provide a more robust account of the populations of western lowland gorillas and central chimpanzees?
  • The 13-year analysis, the largest gorilla and chimpanzee survey in history, allowed scientists to fill in the gaps between previously surveyed areas.
    • The research spanned “59 sites in five countries surveyed between 2003 and 2013, totaling 61,000 person-days of fieldwork.”
    • The survey included foot patrols, investigation of gorilla nests and habitat, and spatial modeling.

 

• The new survey estimates 361,900 gorillas and 128,700 chimpanzees in Western Equatorial Africa. Does this mean gorillas are no longer endangered?
  • No! All species and subspecies of gorilla, including the western lowland gorilla, are critically endangered.
    • Critically endangered species are among the most threatened of all endangered species: They face a 50% chance of extinction in the wild within 10 years or three generations. Use our downloadable graphic to better understand the categories and criteria of endangered species.

 

• What factors put gorillas at risk?
  • The authors title their paper “Guns, germs, and trees.” There’s your answer.
    • guns. Although it is strictly “illegal to kill or capture any great ape in all the nations where they live … poaching to supply bushmeat to fast-growing cities is rife.”
    • germs. “Outbreaks of Ebola virus have also decimated populations in recent decades, with ‘catastrophic’” outbreaks wiping out 90% of a gorilla community within six months.
    • trees. Habitat destruction (deforestation resulting in felled trees) is probably the single leading threat to gorilla populations. The most predominant form of habitat destruction is agricultural development for palm oil plantations.

 

• How can local and global communities contribute to gorilla conservation?
  • Locally, the “most important single factor in determining the survival of gorillas was the presence of park guards to deter poachers.”
  • Globally … we need to rethink our consumer choices and economic development strategies. There are no easy answers.
    • How can we support smallholder farming without encouraging palm oil plantations? Learn more about smallholder farming here and the palm oil industry here.
    • How can we support economic development in underdeveloped nations without putting their natural resources at risk?

 

DISCUSSION IDEAS

The Guardian: Gorillas are far more numerous than previously thought, survey reveals

Nat Geo: Analyzing the Distribution of Vegetation Zones and Mountain Gorillas in Virunga National Park

(extra credit!) Science Advances: Guns, germs, and trees determine density and distribution of gorillas and chimpanzees in Western Equatorial Africa