home
Living Documents
navigation bar
 
 
Prints, nests and dung piles

by Frans van der Helm

Ethno-ecology, Dr Atanga Ekobo of WWF calls it.


"We're collecting information on the ecology and biodiversity of the area and on the way natural resources are being used by people," he explains.

"It will play a vital role in the demarcation of the reserves that are planned here. But there are big logging interests at stake - that's one reason why we try to count and record animals and the value of certain parts and plants as objectively and methodically as possible."

For their survey, WWF zoologists collect data on many animal species, concentrating on the larger mammals. At the same time, a team of botanists is drawing an inventory of the abundant plant life.

The most efficient way of surveying a tropical rainforest is through the use of line-transects - straight tracks through the dense vegetation. The census focuses on the proposed Boumba Bek and Nki reserves and their surroundings which cover some 11,560 sq km.

The area has been divided into 107 cells of 100 sq km each, and one transect will be surveyed in each cell. An advanced Geographic Position System informs the scientists about their exact position.

We meet the zoological team and share a canoe in which to negotiate the pitch-black Dja river at night. They have returned after two weeks in the field.

Even after a short period in the rainforest, your body starts changing in a fascinating way. The field workers return with an interesting array of bumps, minor wounds and infections.

"Mainly because of fatigue" field botanist Valentine Eyabi Njo explains. "Sometimes visibility is only a few metres. When you get tired, you start stumbling over fallen logs hidden by vegetation, or you crash into an excavation made by elephants searching for roots or minerals. You misjudge heights and hit branches with your head."

The mammal census has already indicated that the area is very rich, even by international standards.
These forests might be among the richest in the world. Elephants, gorillas, chimpanzees, African buffalo, bongo, sitatunga, giant forest hog, black and white colobus.... they are all here, and many more besides. Several species of red forest duikers live here as well, and you often encounter greater white-nosed, De Brazza's and moustached monkeys, not to mention grey-cheeked mangabeys. And the high densities of species such as the yellow-backed duiker and the giant pangolin are very promising. Their populations are usually the first to crash when hunting pressure exceeds low intensities.

Apes do not remain stationary - but their nests do. They can be used for estimating chimpanzee and gorilla densities along line transects. According to their age, gorilla and chimpanzee nests fall into several categories. Fresh: odour still present. Recent: vegetation still green for the most part. Old: intact but all vegetation dead. And, finally, Very old: showing advanced decomposition. Comparable classification applies to dung, too: the diameter gives information about the age of the animal.

In the field, a broad array of nest-types is encountered and classified. Chimpanzees' tree nests are constructed by bending and breaking branches to form a sleeping platform. Gorillas almost always sleep on the ground. Luckily, both gorillas and chimpanzees still occur together in the proposed Boumba-Bek and Nki reserves.

The large rounded, shiny green leaves of the Boboko plant, which dominates the vegetation at ground level, offer perfect nesting material. You also find them in day-nests - constructed when a gorilla decides to have a nap in comfort.

The deep footprints of elephants in marshy forest areas are easily seen. For counting elephants, their often massive dung balls come in handy: when fresh, they are hard to miss! Even older ones remain visible for a long time: like small brown compost-heaps, they are scattered over the forest floor. The seeds eaten by the elephants that survive the long journey through their digestive system take full advantage of their new surroundings and spread out from the heaps towards the light.

In these dense forests, meeting elephants is a thrilling experience, but you have to be prepared for short-tempered reactions. Agnes Eyo, a trainee from Nigeria, explains:
"The best thing is to climb a tree before the animal has seen you - otherwise it knows you're there and waits for you. You can also hide behind a large trunk. Elephants can detect you by smell, but you can keep out of reach. Making sounds can scare them off, so we carry whistles. In risky situations we even clap our hands or bang jerrycans together."

On occasions, chimpanzees threaten humans, but only from a distance. "Even gorillas come to take a curious look, but they are always very cautious," adds Agnes Eyo.
"For us, it's a great opportunity to work in conservation and get the real forest experience!"

Another transect-line and another team. Dr. Bernard-Aloys Nkongmeneck, botanist at the University of Yaounde, searches for plants that can be used as food or for medical purposes on a long-term basis.

These expeditions deep into the forests are combined, of course, with meticulous scientific work. All kinds of data are laboriously noted down, and collected plants or their parts are handled carefully. Each twig or specimen is folded into newspapers imported specially for the purpose. Metal sheets and a wooden frame are attached to keep everything securely in place.

There must be some 2,000 species of trees and bushes here - 3,000 if you include smaller plants. This is an unique area, partly because the canopy is fragmented. These gaps may be caused by wind, elephant activity or burrowing species like the aardvark.

In this same south-east area, some important tree species are threatened by logging. Now, the botanical team is involved in another kind of research. "We're finding out which species are under particular threat," explains Dr Nkongmeneck.
"We're also looking at the subtle relations between plants and animals in these virgin forests - the decline of even one tree species may have great impact on everything else."

And that is why WWF's work in the field is never finished.

© WWF

 
bottom navigation bar