By Drew T. Cronin, Joshua Linder, Nelson Ting and Ekwoge Abwe – Coordinators of the Red Colobus Conservation Action Plan
Red colobus monkeys (Piliocolobus spp.) are a group of leaf-eating monkeys unique to the forests of sub-Saharan Africa, ranging from Senegal on the Atlantic coast to the island of Zanzibar in the Indian Ocean. Despite their broad range, red colobus monkeys have the regrettable distinction of being the most threatened group of primates in Africa. Experts are unclear about exactly how many species of red colobus there are, but we know there are at least 18 distinct forms, differing from one another in aspects of coat color and design, facial patterns, behavior, and vocalizations. Every form of red colobus monkey, unfortunately, is threatened with extinction.
Current distribution of the various red colobus taxa. (Image: © Red Colobus Conservation Action Plan)
The IUCN Red List of Threatened Species considers more than half of red colobus forms Endangered or Critically Endangered. Five red colobus taxa–Niger Delta Red Colobus (P. epieni), Pennant’s Red Colobus (P. pennanti), Preuss’s Red Colobus (P. preussi), Miss Waldron’s Red Colobus (P. waldroni), and Tana River Red Colobus (P. rufomitratus) appear on the list of the World’s Top 25 Most Endangered Primates. Miss Waldron’s Red Colobus may have been hunted to extinction already, and GWC’s Search for Lost Species program considers it one of the world’s “most wanted” lost species. Despite the conservation status of red colobus, researchers have studied only a few populations in detail and the general public is largely unaware of these monkeys. General awareness of red colobus and their plight is further hindered by the lack of any captive populations in zoos around the world–animal husbandry experts have not been able to successfully care for them in captivity. Red colobus monkeys are therefore facing an extinction crisis requiring urgent, targeted, and coordinated conservation action.
Illustration of the 18 red colobus forms. (Illustration: © Stephen Nash)
The primary threats to red colobus are commercial and subsistence hunting, disease, and habitat loss, degradation, and fragmentation resulting from numerous factors (i.e., logging, mining, charcoal production, infrastructure development, and conversion of forest to farms and agriculture plantations). Unfortunately, red colobus are more susceptible to hunting and habitat degradation than other monkeys and are usually one of the first species to disappear in disturbed habitats. Like a canary in a coal mine, loss of red colobus monkeys can be thought of as the first indicators of the decline of a healthy ecosystem.
A concerted and coordinated range-wide conservation effort is urgently required to conserve and recover all red colobus forms. In response to this critical need, the IUCN Primate Specialist Group, in collaboration with the African Primatological Society, is spearheading the first comprehensive Red Colobus Conservation Action Plan (ReCAP). Experts on all red colobus forms and their range countries are contributing to this action plan to unite and mobilize local and international conservation groups, governments, academic institutions, zoos, and other interested partners to prevent the further decline and loss of red colobus populations.
We expect to launch the ReCAP and an associated program of conservation work at the International Primatological Society (IPS) Congress in Nairobi, Kenya 2018. It is important to note, however, that we are not just looking to write an action plan, but to catalyze coordinated range-wide conservation action for red colobus monkeys and their habitats. The overarching goals of the ReCAP are to: enhance and expand site-based conservation for all forms of red colobus monkey; elevate red colobus monkeys to flagship status across their range and beyond; develop cross-cutting, continent-wide initiatives to link and support site-based activities; and, build capacity and create opportunities through training and mentoring programs.
This month, which included Endangered Species Day on May 18 and the International Day for Biological Diversity of May 22, we highlight the top five most threatened red colobus species, which are all Critically Endangered. We believe that through both site-based projects that ensure protection through enforcement, education, and ecological monitoring, and regional initiatives that leverage common solutions to achieve efficiencies of scale and range-wide adaptive management, no red colobus monkey needs go extinct.
Top 5 Most Threatened Red Colobus Taxa
Miss Waldron’s Red Colobus (P. waldroni) (Illustration: © Stephen Nash)
Miss Waldron’s Red Colobus (Piliocolobus waldroni): Critically Endangered
Once found throughout southeastern Cote d’Ivoire and southwestern Ghana, extensive hunting and habitat loss have resulted in steep declines in its population. They have not been observed in the wild since 1978, despite extensive surveys. Experts believe that it may be extinct, but rumors of their existence persist from the deep interior of a single, remote, almost impenetrable swamp forest.
Niger Delta Red Colobus (P. epieni) (Photo: © Noel Rowe/alltheworldsprimates.org)
Niger Delta Red Colobus (Piliocolobus epieni): Critically Endangered
The most recently discovered red colobus species is already one of the most endangered. First described in the 1990s, the Niger Delta Red Colobus is found only in Nigeria, restricted to the swamp forests of the Niger Delta in an area of approximately 78 km squared. Its habitat has been severely degraded by logging, and hunting has increased due to the influx of oil workers to the region. With only about 200 individuals remaining, it is thought that it may go extinct within the next five years without effective conservation actions.
Tana River Red Colobus (P. rufomitratus) (Photo: © Stanislaus Kivai)
Tana River Red Colobus (Piliocolobus rufomitratus): Critically Endangered
This species is found only in small forest fragments along a 60-km stretch of river, in a total area of less than 13 km squared. Only around 1,000 individuals remain, but it is in continual decline due to rapid loss and fragmentation of its habitat. The endangered Tana River Mangabey is also endemic and restricted to the same forest as the Tana River Red Colobus.
Pennant’s Red Colobus (P. pennantii) in the Gran Caldera de Luba, Bioko Island, Equatorial Guinea. (Photo: © Ian Nichols | Bioko Biodiversity Protection Program)
Pennant’s Red Colobus (Piliocolobus pennantii): Critically Endangered
Biologists believe that Pennant’s Red Colobus, endemic to the small island of Bioko in Equatorial Guinea, were once found throughout all of Bioko’s lowland forests. Heavy hunting pressure and increasing infrastructure development, however, have reduced its range to only the most remote, mountainous corner of the island, in an area of about 150 km squared. Fewer than an estimated 1,200 individuals remain, a decline of more than 80 percent over the last 30 years due primarily to the proliferation of the commercial bushmeat trade. The critically endangered Bioko Black Colobus (Colobus satanas satanas) and endangered Bioko Drill (Mandrillus leucophaeus poensis) are also endemic, along with six other endangered primate taxa, and found in the same forest as the Pennant’s Red Colobus. As such, this species is a notable flagship for the primate fauna of Bioko Island.
Preuss’s red colobus (P. preussi) in Korup National Park, Cameroon. (Photo: © Alexandra Hofner)
Preuss’s Red Colobus (Piliocolobus preussi): Critically Endangered
Restricted mostly to two separate forests in western Cameroon, this species requires urgent support. Surrounded by some of the densest human populations in Africa, it is in sharp decline due to intense, commercialized bushmeat hunting and deforestation caused by expansion of small- and large-scale agriculture and infrastructure projects.
This post was co-authored by the coordinators of the Red Colobus Conservation Action Plan: Drew T. Cronin, Joshua Linder, Nelson Ting, and Ekwoge Abwe. For more info on the Red Colobus Conservation Action Plan, check out our website www.piliocolobus.org or follow us on Twitter at @RedColobusAP.
(Top photo: © Raffaele Merler)