27.09.2024. Meticulously documenting individual animal counts and strategically positioning camera traps, PhD researcher Joeri Zwerts found that FSC-certified concessions have a significantly higher population of large and threatened mammals - 2.7 times more mammals over 100 kg, such as gorillas and forest elephants, and 2.5 times more mammals weighing 30-100 kg, such as leopards and chimps - than non-FSC-certified forest concessions.
The number of smaller animals seen was equal in FSC- and non-FSC concessions, indicating that the latter have less biodiversity. The results were comparable in Gabon and the Republic of Congo.
Below is part 2 of our interview with Joeri Zwerts, now Assistant Professor at the University of Utrecht.
IHC: In the course of your research, did you notice the presence/absence of more/less species than would normally inhabit the tropical forest?
JZ: The difference in species diversity was random. The Congo Basin is a fairly interconnected stretch. There are cities and roads but not as many as elsewhere. Hunting exists but species are not extirpated. That is also why the study is so strong: previous studies looked at species diversity to show FSC impact, but we also need to take population sizes into account.
IHC: Whilst forestry is the main reason for road building in the Congo Basin, do roads invariably result in deforestation and loss of wildlife?
JZ: We open up roads which creates hunting pressure, but we can also manage roads to relieve that pressure. That is a choice. It has to be done. Roads also create microclimate differences: more winds, drier climate. It is important to keep areas without roads.
IHC: You must have come across eco-guards and local communities during your research. How did they see the work you were doing?
JZ: People have different perceptions. Forests are perceived as an endless resource, they will always be there. In Europe, forests have been replanted. So our perception is different.
I joined eco-guards on a 3-day anti-poaching mission to learn how they work. In some regions, as part of the eco-guard strategy, there are awareness-raising sessions on why some species need to be protected. That is important to align local perception and motivation with protection.There could be a lack of insight in the realization/ambition to protect the forests. More immediate concerns: economically challenging regions to live in.
IHC: How many years did you spend travelling? What is the maximum length of time you spent in any given forest?
JZ: We started in 2017 (January) and a lot of preparation was needed: we went to the field in 2018 for 4 years, including the COVID crisis when I was not allowed to enter Congo for 8 months. The longest I did was 12 days in a row: a camp every night in a different place, find water, cook, break up the camp, start walking with the camera traps.
IHC: Who were your guides?
JZ: I had 60 employees who were recruited locally, including local guides with machetes. We heard a lot of stories, learned that so many plants are edible, and have different nutrition and medicinal values. The locals know the forest inside out. Some of the plants were completely unknown to us, but the villagers knew them. I am still in touch with some of them.
IHC: Did you encounter many animals?
JZ: You do notice a lot of animals, although they are careful not to be seen.
The forest is a big game of hide and seek: larger animals do not need to be extremely safe but even gorillas are when it comes to protecting their young. We ran into a gorilla, a big silverback, quite intimidating. Had he decided to attack, there was nothing we could have done.
You see gliders, birds, scorpions. Or, you hear them – chimps are screaming. The chimps are really curious.
Sometimes you walk for km on end on elephants’ footsteps. Elephants have cushions under their feet, so you cannot really hear them. They are able to move through the forest very silently. When you see them, you want to back off slowly.
One day we were walking along a harvesting sandroad and a leopard sneaked into the forest, right where we were heading to.
We always kept the fire going at night.
IHC: How to explain the presence of animals in concessions that are used for wood harvesting and processing?
JZ: Elephants are so intelligent that they know where it is safe. Elephants never cross the roads that are known by them to be unsafe. When one elephant was found (via GPS collars) to have crossed a road that was unsafe, she ran 14 times faster than her normal pace. Maybe that also explains why there are so many elephants in FSC-concessions!
IHC: Did you find the presence of animals in/close to/around harvesting areas? What about, far from harvesting areas? Were there less or more animals?
JZ: We did not look at this – after harvesting there are fresh shoots and easily palatable plants. Interesting for leaf eaters such as gorillas. So animals are mobile and they can come back. They might be afraid but are usually able to return. I tried to avoid active logging areas.
IHC: Did you find the presence of Ebola or other viruses in any of the areas?
JZ: In 2002 or 2000 there was an Ebola outbreak in Gabon and 90% of primates died. It takes a long time for species to recover, locally. Harvesting brings people into the forests and we should prevent disease from spreading from humans to animals.
IHC: How is climate change impacting forest species, trees and animals?
JZ: There are studies that show that fruiting is slowing down because temperatures are rising – if temperatures are not low enough, there will be no flowers and then, no fruits. This can lead to conflict between animals and humans. That will be the focus of my next research.
IHC: Why, do you think, classic concessions have fewer animals than those with FSC certification? A coincidence or a pattern? Which could be the cause?
JZ: The difference lies in what measures are being implemented. Closure of roads, anti-poaching patrols, incentives for alternative protein sources, vehicle checks… in FSC-managed forests, forest protection is externally checked (the process is known as an audit) where the need is highest, i.e. in the forest itself.
IHC: Many rely on satellite observation to decide whether a forest is healthy (or not). Why is research in the field important?
JZ: Satellite observation should be part and parcel of an assessment which includes other aspects. There is too much emphasis on remote sensing. What happens below the canopy, cannot be remotely sensed! Take forest health. Roads can be managed so that wildlife is not compromised. We can still retain ecological intactness. Of course, harvesting still has a temporary impact. Overall, for the large part of the concession, those impacts can be mitigated. However, pristine areas should be maintained.
IHC: Do you think it would be good to repeat the research in the same concessions?
JZ: There are so many research questions to address: the sustainability of timber stocks, human-elephant conflict, the longevity of FSC certified concessions (what happens if a certain company leaves)?
IHC: So ultimately, what should we do to better protect animals and, forests?
JZ: Come back to the data we produce: YES, there are ways to effectively protect the most vulnerable species in the forest. NO, there is no reason not to protect wildlife.
IHC: How do you see the future of FSC-certified concessions in the Congo Basin?
JZ: FSC implementation ensures forests stay healthy, wildlife thrive and communities live in and from the forests. Based on our results, there is no way around it: all forest countries should go for FSC certification. It is imperative that the wildlife in these forests stay protected. Nobody benefits from empty forests.
IHC: If the animals in the images you have taken could speak, what would they say?
JZ: Animals have an intrinsic value, they have a right to exist. Forest peoples have been hunting for millennia and they should continue. Wildlife is important for protein provision. What should be prevented is commercial hunting. We have a duty to reduce our impacts on animals!
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About Interholco
The valorisation of a natural forest of 1.16 million hectares in the Republic of Congo Brazzaville is our DNA here at INTERHOLCO. As an FSC® (Forest Stewardship Council®, FSC® C022952) and PEFC and PAFC certified producer, INTERHOLCO is a well-established player in the trade of its edged boules, sawn timber, glue laminated scantlings, decking boards and more.
We are a leading provider of high-quality wood products ‘Made in Africa’ holding a verified environmental and health performance statement (FDES requirement in France). Our teams carefully manage the supply chain from forest to customer. Our story is fully illustrated by enabling the people living in Ngombe to access better life conditions. We make it possible to design and build a healthy living environment with bio-based, eco-friendly materials, one of the real solutions for the planet and climate. Follow us on LinkedIn
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