Forest Elephants of Gabon

I was saddened to read about the 26 forest elephants recently slaughtered at the Dzanga Bai in the Central African Republic. My affection for forest elephants dates to a spell of five years living in Gabon in the 1990s and I wrote the following short article at that time, before forest elephants were separated from Savannah elephants as separate species, Loxodonta africana africana and Loxodonta cyclotis.


Pygmy Elephants, Forest Elephants and Savannah Elephants 

What do all those common names mean?

The Pygmy Elephant as a separate race of elephants has always been controversial. In 1906, a zoologist named Noack invented the new sub-species Elephas africanus pumilio for a small elephant measuring only 1.2 m at the withers (the ridge between its shoulder blades). Unfortunately for him, the animal continued to grow until it reached 2.03 m at its death, nine years later, a perfectly normal size for a forest elephant! Several other elephants also continued to grow after they had been classified as belonging to the pygmy subspecies. So far, there is no evidence in favour of the existence of this subspecies, but some zoologists maintain an open mind, since forest elephants have been so little studied.

Far less controversial is the distinction between forest and savannah (or bush) elephants. The main features that distinguish the forest form (Loxodonta africana cyclotis) from the savannah form (Loxodonta africana africana), are that it is smaller,  has more rounded ears, a flatter forehead, and has thinner tusks (see Figure 1). A general rule is that a group of elephants is assigned to the forest form if the average shoulder height of all the adult animals measures less than 2.4 m. In contrast, savannah elephants may reach shoulder heights of 3.5 to 4 m, with a huge 4.45 m having been recorded in one Namibian elephant. Gabon is thought to contain about 60,000 +/- 20,000 of Africa’s forest elephants (often known here as Assala). A 1987 study came up with a population estimate of about 330,000 forest elephants in Gabon, Congo and Zaire.





Figure 1. Differences between Forest and Savannah (or Bush) elephants. Left: Savannah elephant, South Africa; Right: Forest elephant, Gamba.

How to estimate elephant heights?

There’s an easier way than directly measuring the beasts themselves: measure their footprints. A commonly used relation is that the height of an elephant at its withers is approximately twice the circumference of its forefoot. Alternatively, the height of the elephant is about 6.33 times the length of the rear footprint minus 19 cm (or L = 0.158H+ 3 cm).

How to tell a forefoot print from a hindfoot print?

The forefoot print is close to circular and is larger than the more elongate hindfoot print. The print of the hindfoot commonly overprints that of the forefoot and may show a scuff mark where it was dragged off the ground. The forefoot print is not scuffed since the elephant lifts its fore foot as it walks.

Sizes of elephants in Gabon and elsewhere in West Africa

The sizes of elephants as inferred from their fore-footprints have been studied in the Tai National Park of Cote d’Ivoire and the Bia National Park of Ghana (Figure 2). For comparison, in an attack of curiosity, I collected measurements from the Gamba area (between Sette Cama and Colas Beach). The results are shown in the graph in Figure 3.



Figure 2Places in West and Central Africa where the heights of elephants have been estimated from their footprints.



Figure 3. Comparison of elephant sizes inferred from the sizes of their fore footprints, In Gamba, Cote d’Ivoire and Ghana.







The Tai elephants, of which 97% had inferred heights of less than 2 m, were clearly all in the Forest Elephant class (Loxodonta africana cyclotis). In Ghana’s Bia National Park, however, there is a gradation towards the scale of savannah elephants (Loxodonta africana africana). In Bia and its surrounding area about half of the elephant prints indicated heights of over 2 m. The Bia National Park lies only about 100 km south of savannah territory, so perhaps these include forms intermediate between forest and savannah elephants. The Gamba measurements are very similar to those of the Tai National Park, with a most common height of about 1.6 m, and indicate that all animals belong in the Forest Elephant class.

Data on the lengths of hind-footprints have been previously collected from three other areas in Gabon during a nationwide survey of forest elephants. These were the Reserve de Petit Loango, Reserve de la Lopé and Oveng. The graph in Figure 4 shows the distributions of elephant heights inferred from these measurements (using the relation described above), with the inferred heights from Gamba (using the forefoot prints) for comparison. The distributions are all broadly similar, with most common heights around 1.6 to 1.8 m and largest sizes of about 2.3 to 2.5 m.



Figure 4. Comparison of elephant sizes inferred from measurements of footprints in four 
areas of Gabon.


Habits of forest elephants

Unlike savannah elephants, forest elephants tend to occur in small family groups, rarely with more than 8 individuals. An exception to this was a sighting of a group of 35 in December 1975 to the north of Koumaga (Morel & Morand 1983). One reason for the pygmy elephant misconception was that in the less threatening environment of the equatorial forests it is safer for a young forest elephant to leave parental protection than it is for its savannah counterparts. Solitary young animals have thus been mistaken for adults. Adult males are generally solitary.

During the year they migrate seasonally between habitats, guided by the locations of fruiting trees (such as the Palmera palm) and fresh water. Around Gamba the frequency of elephant sightings tends to correlate with the two dry seasons (the main one from July to September and the minor one from January to February). In general, they like to commute between the forest, where they can find fruit trees, and clearings where they can find grasses (and bananas!). In the forest, elephant tracks often lead to large fruit-bearing trees. Some of these trees appear to depend entirely on elephants for the dispersal of their seeds.

In conclusion


Our local "longnoses" are fine and characteristic representatives of the small, poorly known, forest race of African elephants.  When you see one it’s worth remembering that these are not the Savannah elephants easily seen by millions of tourists in east and southern Africa. Several zoologists have suffered greatly to get a look at this form of elephant (see for example the recent National Geographic article on Congo’s Ndoki National Park). 

Referring wistfully to the study of forest elephants in West Africa, Claude Martin (1991) says, “In the forest one learns to make do with footprints”.

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