The study has been published today in Proceedings of the National Academy of Sciences (PNAS).
Scientists found only a few small "areas of compromise" in Africa with a high suitability for oil palm cultivation and a low potential impact on the primate species living there.
These areas totalled 0.13 million hectares (Mha), which is less than 0.005 % of the total land mass of the African continent.
Even when taking into account all areas with at least minimum suitability to grow the plants from which palm oil is extracted, just 3.3 Mha of land is available to produce the oil without endangering primate populations.
This amounts to only 6.2% of the 53Mha that would be required to cope with rising palm oil demand by 2050.
With the demand for palm oil steadily increasing, and the industry looking for new possibilities for expansion beyond Southeast Asia and South America, the study shows how it will be extremely challenging to reconcile conservation targets with future conversion of land to oil palm crops.
Palm oil production expands as the world's population grows
Palm oil can be found in about half of all packaged products in the supermarket, from food to makeup and cleaning products.
It is also used in some biofuels. Production is steadily rising, and expected to accelerate as the world’s population continues to grow and demand for these products increases.
Most oil palms – the plants from which palm oil is derived - are currently grown in Southeast Asia and, to a lesser extent, in South and Central America.
Africa is considered as a likely destination for new plantations, thanks to the abundant low-lying tropical ecosystems that are highly suitable for profitable oil palm cropping.
Lessons learned from the catastrophic impact of industrial oil palm plantations on wildlife in Southeast Asia prompted the international team of researchers, from the JRC, CIRAD, Stellenbosch University, Liverpool John Moores University and ETH Zurich, to produce a broad assessment of the expected effects of oil palm expansion on African primate diversity, highlighting the challenges that lie ahead.
Primate diversity: a good indicator of ecosystem health
The researchers chose to focus on primates for multiple reasons. The most obvious one is that primates are a priority for conservation.
Populations of many primate species are already in steep decline as large parts of their natural habitat are exploited for agriculture, logging and mining. Indeed, 37% of primate species in mainland Africa and 87% of species in Madagascar are threatened with extinction.
"Primates offer us a detailed view on ecosystem health, as they play an important role in seed dispersal and maintaining the composition of forest communities" explains Giovanni Strona, lead author of the study.
"Primate diversity correlates with the diversity of other plant and animal groups, which implies that the potential impact of future oil palm expansion we modelled for primates could extend to biodiversity in general. The home ranges of most African primate species are relatively well known, which made it possible for us to confidently use them in our large-scale analysis."
Mitigating the dangers of future expansion
Researchers produced and then compared two maps, one on primate vulnerability and the other on suitability for oil palm cultivation.
The maps revealed striking similarities across sub-Saharan Africa, with areas of high primate vulnerability and high oil palm suitability overlapping in equatorial and forested regions across West and Central Africa.
"Some levers for the successful conservation of African biodiversity do exist, based mainly on realistic mitigation strategies," says Ghislain Vieilledent, co-author of the study.
"One strategy would be to identify alternative trajectories for agricultural expansion, using "smart" criteria and minimising the loss of primate habitat.
Another important one could be intensifying yields through the use of high quality seed and better breeding technologies.
Acknowledging that the real world application of such criteria can be problematic, researchers compared four oil palm expansion scenarios:
- two income-driven scenarios, based on either land suitability or accessibility;
- two conservation-driven scenarios, based on either minimising carbon dioxide emissions or first converting areas of low primate vulnerability.
The scenario based on land suitability led to the highest cumulative loss of primate habitat.
In the primate vulnerability scenario, the number of primate species significantly affected by oil palm expansion could be kept relatively low.
Nevertheless, even in this "optimal" scenario, more than five species, on average, will lose 1,000 ha of range land for every 1,000 ha of land conversion.
An increase in demand for palm oil for biodiesel would further ratchet up the demand for land conversion, highlighting the importance of future transport emissions policies.
National and international policy initiatives, alongside voluntary schemes such as the Round Table on Sustainable Palm Oil (RSPO), also have the potential to mitigate large-scale deforestation.
To tackle the problem at source, government policies and retailer-led initiatives could help modify consumption patterns and reduce the increase in future global demand.
However, this requires additional actions, among them raising consumer awareness about the environmental consequences of their lifestyle.
"There is already a momentum for change, with many people worldwide starting to realise how their daily choices can have a significant impact on far away, vulnerable ecosystems." concludes Giovanni. "We hope that our findings could represent another important step in this constructive direction".