The extinction of our closest biological relatives may be closer than we think, but through organized conservation efforts that focus on the human condition, there is still hope for non-human primates, says Joanna Lambert, professor of anthropology at the University of Colorado Boulder.
Lambert was co-author on a recently published study that brought to light the likely extinction of most of world’s primate species. The study investigated what was causing 75 percent of worldwide primate populations to decline, and 60 percent of species to be threatened with extinction.
The study, which was published in the high-profile journal Science Advances, looked at the 504 known species of primates across the globe, the causes of population decline, and how they varied by region. It also described conservation strategies based on the collaborative research and findings of the 30 other scientists.
Researchers suggested a broad range of strategies, each one playing an important role in addressing both human and ecological needs. These conservation efforts include but are not limited to expanding protected areas, lowering global-market demands for resources from primate habitat countries, reforesting lost habitat, engaging in more sustainable land-use and recruiting local and global citizen support.
The study’s authors say looming extinction “is a result of escalating anthropogenic pressures on primates and their habitats.” It lists the various factors responsible, citing the International Union for Conservation of Nature’s (IUCN) Primate Specialist Group, of which Lambert is a consulting member. The group found that the major threats to primate populations include habitat loss due to agriculture, logging, livestock ranching and hunting.
An expanding agricultural frontier is the primary cause of primate habitat loss and population decline in every region. It affects 76 percent of primate species globally.
The threat of human activity on primate species varies by region. In the Neotropics—tropical areas of Central and South America—deforestation for livestock ranching is the second major driver of primate-population decline. In mainland Africa, Madagascar and Asia the second major threat is hunting and trapping, affecting upwards of 90 percent of primate species.
Logging is the third major threat in all regions, affecting 60 percent of species globally.
The study looked at the IUCN Red List—billed as the world’s most comprehensive inventory of the conservation status of species—and compared it to peer-reviewed sources and U.N. databases to evaluate the level of impact humans impose to primate survival. Conservation both locally and globally is the focus of the Science Advances article; it makes an argument for the importance of primate species not only to the natural environments to which they belong, but also as social and cultural agents.
For instance, in the Lindu highlands and Buton island of Sulawesi in Indonesia, humans live with monkey species such as macaques because of their role in local folklore and agriculture. The macaques eat the fruit of the cashew, but let nuts fall to the ground to be harvested by farmers. This is an instance of mutualism and coexistence between humans, primates (and other animals), and plants that Lambert wants to highlight.
So while the results of the study reveal shocking statistics regarding primate populations, this crisis is more than monkey business. Professor Lambert’s research goes beyond counting silverback gorillas in mainland Africa; it looks at the nuanced interactions between plant, animal and human species sharing the same habitat.
“My role in writing the article was with regards to ecology, more specifically the interactions between primates and plants and the critically important role of primates as seed-dispersers and agents of forest regeneration throughout the tropics,” Lambert said.
Primates serve as key operators to maintain their environments as pollinators and seed-dispersers. For example, the lemurs of Madagascar rely on Malagasy tree species for food. The trees rely on the lemurs to distribute their seeds, but with declining lemur populations these trees are less likely to regenerate and mature.
Diminished seed viability and plant species diversity due to declining primate populations are also being documented in mainland Africa, Central and South America, and Asia.
“Ultimately, good conservation biology and the application of conservation methods rests on basic science and basic research” said Lambert. Her research has had policy implications in the past. Lambert has developed mechanisms of conservation that she has proposed to the Wildlife Authority in Uganda, where she has worked for 26 years.
The first question in conservation is whether to focus on conserving species or habitat. Lambert has proposed conservation tactics that focus on particular primate species. “If we conserve a subset of primates, we also conserve all of their seed-dispersal services and all of the plants that require the seed-dispersal services of those primates. It’s what we call an umbrella tactic in conservation.”
Currently, countries in the Neotropics, mainland Africa and Asia are all reducing the amount of protected areas to support the growing pressure for industrial natural-resource extraction.
Even with a reduction in conservation areas, any protected habitat is still important. For example, colobine primate populations in the mountains of Tanzania were stable within the protected areas, but faced severe population declines outside of that protected area.
The study proposes that the key to primate species conservation lies in improving the human condition.
“The first thing to recognize is that environmental degradation is differentially impacting human populations, such that it is influencing individuals who are already disadvantaged more than those individuals that are in a higher socio-economic status” said Lambert.
Professor Lambert is optimistic about the future of non-human primates. “That is absolutely the most important emotional variable in the pursuit of conservation,” Lambert said. “If we lose hope, if we lose optimism, that’s when everything grinds to a halt.”
There is reason to be optimistic. “We are conserving more habitat all the time,” said Lambert. “There are a number of examples of a changing ethic in the way people think about our planet, and there are also a number of examples of conservation success, and we have to hold on to those.”