Eastern vs western gorillas – what are the differences?

There are only two gorilla species in the world, each with two subspecies, as shown in the infographic below.

Eastern gorillas (gorilla beringei) are quite a bit bigger than western gorillas (gorilla gorilla), with the eastern lowland gorilla being the biggest of all. A healthy, fully grown male eastern lowland gorilla can weigh between 150 and 209 kg (331 and 461 lb)! The western lowland gorilla is the smallest of all the subspecies.

Eastern gorillas have longer, thicker and darker fur, with mountain gorillas having the darkest fur of all. The fur of western gorillas can be grey or brown, with the forehead sometimes being a little red.

As we discuss in Where do gorillas live?, all wild gorillas live in Equatorial Africa. To be more specific:

Mountain gorilla mother with her infant

As the names suggest, the two subspecies of the eastern gorilla live primarily in regions of different elevations. We say primarily, because the eastern lowland gorilla actually has a wide range of habitats, including mountains. But it earned its common name because it can often be found in lowland rainforest, swampland and even peat bogs. Mountain gorillas, on the other hand, live only in high-altitude montane rainforest.

A male western lowland gorilla

Cross river gorillas live near the headwaters of the Cross River in the Cameroon–Nigeria border region and nowhere else. While it's a small region geographically, their altitudinal range is impressive, ranging from 100 to 2,037 m (328 to 6,683 ft) above sea level.

Western lowland gorillas have a far, far broader range. In fact, they have the broadest range of all gorilla subspecies, living between sea level and 1,300 m (4,300 ft). Their various habitats including swamp forest, rainforest, brush and abandoned farmland. Some western lowland gorillas are also kept in zoos around the world.

All of the four gorilla subspecies are endangered. However, mountain gorillas are faring a little better than the others in an important way: their numbers have been increasing in recent decades, while the numbers of the other subspecies are still in decline. It's for this reason that mountain gorillas are now classified as only endangered, while the others remain classified as critically endangered.

The upwards trajectory of mountain gorilla numbers doesn't, however, make it the most populous subspecies. According to the Cross River Gorilla Organisation, population figures for the different subspecies are as follows:

The core impetus behind the improved situation of the mountain gorilla was the work of Dian Fossey and her book Gorillas in the Mist. Fossey brought the plight of mountain gorillas to the world's attention, and this international concern in turn helped to spark funding for conservation efforts. This broader awareness also led to the development of mountain gorilla trekking safaris, which provide further essential funding.

The other three subspecies of gorillas also receive some funding through gorilla trekking safaris, but such tours aren't nearly as well supported, for a few reasons. The main reason is that the other types of gorillas live in countries deemed by many to be unsafe for tourists.

A mountain gorilla trekking tour group

Most people who want to see mountain gorillas in the wild head to Uganda or Rwanda. Both of these countries are pretty safe for tourists, and both have well-organised gorilla trekking industries.

In Uganda, there are two parks with mountain gorilla populations, and you can go trekking in either: Bwindi Impenetrable National Park and Mgahinga Gorilla National Park. In Rwanda, all of the country's mountain gorillas live within Volcanoes National Park (or Parc National des Volcans in French), and gorilla trekking tours are on offer here too.

We at Follow Alice offer gorilla treks in Rwanda as well as gorilla treks in Uganda. Unsure which country to visit? Please read our post Gorilla trekking in Rwanda vs Uganda – which is better?

Kahuzi-Biega National Park in the DRC is the main stronghold of eastern lowland gorillas, and visitors have been able to go gorilla trekking there since 2016. That said, it's vital that you please book with a reputable tour operator to ensure you enjoy a safe visit.

As we explain in Where do gorillas live?, it's inadvisable for most foreigners to try to visit western lowland or cross river gorillas. But we do offer some suggestions in that post about where you could consider visiting them.

Finally, please consider supporting one or more gorilla conservation efforts from afar, irregardless of any plans to go gorilla trekking in the future. You can visit the Gorilla Organisation to learn more on how you might be able to help. All of the gorilla subspecies need more support, and there are various ways to help!