Scientists urge greater protection of primates to prevent population extinction in fragmented forests

Wednesday, 22 April 2020

Eulemur collaris News

Oxford Brookes University scientists in collaboration with a team of international experts are calling for greater protection of primates in declining forests, to ensure their survival in the midst of rapid human alterations to habitats and climate change.

There are over 600 species of primates, including apes, monkeys, tarsiers, and strepsirhines (bushbabies, lemurs, and lorises). More than 50% of primates are now threatened by habitat loss and fragmentation, which are unanimously recognized as the main threat to primate survival.

The team have contributed to the publication of a special issue of the American Journal of Primatology: Surviving in fragmented landscapes: Identifying variables that influence primate population viability and persistence in forest fragments, which coincides with the 50th anniversary of World Earth Day (22 April 2020). The issue is co-edited by Dr Giuseppe Donati and Dr Matthew McLennan (both at Oxford Brookes University) and led by Dr Lisa Gould (Emeritus Professor, University of Victoria, Canada).

The special issue includes a collection of twelve papers ranging from studies of a variety of lemur species in diverse habitats and regions of Madagascar, to Bale monkeys in Ethiopia and chimpanzees in Uganda, Javan slow lorises, as well as other Asian and American primates. 

Reversing habitat loss and fragmentation through reforestation projects is of paramount importance. By increasing forest fragment size these actions may improve habitat connectivity for primates and ultimately assist in species dispersal in landscapes modified by human activities.

Dr Giuseppe Donati, Oxford Brookes University

Lead editor Professor Lisa Gould commented: “The goal of this special issue is to examine differing responses to habitat fragmentation by primate populations, and to identify specific factors that can help predict survival in fragmented landscapes. The authors of the papers included in this issue have used varied approaches in addressing this goal. We anticipate that the questions and methods described in these contributions will prove useful for future studies relating to how primates adapt – or fail to adapt – to ongoing forest fragmentation.”

Dr Matthew McLennan of Oxford Brookes University added: “Small forest fragments may serve as essential points to maintain connectivity. It is also imperative to understand the interactions of flora and fauna (including humans) within these modified landscapes, if we are to create effective restoration programmes. Part of the solution could include for example, the planting of non-native plant species, which may play an important role for the re-establishment of primate populations in degraded or small fragments.”

Habitat fragmentation results from rapid human alteration of the natural landscape. On a global scale, fragmentation is a direct consequence of habitat loss because of agriculture, livestock production, logging, road expansions, mining and climate change. The key concerns for conservation experts are the loss of genetic variability because of population reduction and inbreeding, food depletion, increased predation (including human hunting), and disease spread as a result of overcrowding or nutritional stress.

In the collection of papers, fragmentation is discussed from local to pan-regional levels. For example, a project in Java led by Dr Hélèn Birot (Little Fireface Project) and co-authored by Oxford Brookes’ Professor Anna Nekaris and Dr Marco Campera, shows how relatively small-scale human intervention can produce significant benefits.  Critically Endangered Javan slow lorises (Nycticebus javanicus) benefitted from the installation of artificial canopy bridges to move from one forest patch to another, to seek food and shelter. In a second example, Dr Timothy Eppley (San Diego Zoo Global) and colleagues examined how dietary choice and space needs can affect the likelihood of survival of 32 species of lemurs in fragmented habitats of Madagascar. The results of this analysis point to the need for immediate conservation actions, particularly reforestation efforts that take the landscape into account.

In line with previous reports, this compilation of papers confirms that primate survival depends on the ability of individual species to move across gaps between forest fragments, as well as the behavioural and ecological flexibility of a species to cope with resource scarcity and other human impacts.

Dr Giuseppe Donati concludes: “Reversing habitat loss and fragmentation through reforestation projects is of paramount importance. By increasing forest fragment size these actions may improve habitat connectivity for primates and ultimately assist in species dispersal in landscapes modified by human activities.” The editors add that maintaining a permanent presence at field sites is also vital, not only to increase our understanding of primate behavior and ecology, but also to work alongside local communities to generate alternatives to forest destruction.

Discover more about Primate Conservation in the Department of Social Sciences, on the Oxford Brookes University website.

Photo credit: Eulemur collaris by Jennifer Chambler