Collected Evidence: Collected Evidence: Conduct regular anti-poaching patrols Two studies in Rwanda found that gorilla populations increased after implementing regular anti-poaching patrols, alongside other interventions. One study in the Democratic Republic of Congo, Rwanda, and Uganda found that gorilla populations declined after conducting regular anti-poaching patrols. A review on gorillas in Uganda found that no gorillas were killed over a 21 month period when the number of guards carrying out anti-poaching patrols increased, alongside other interventions. One study in Ghana found a reduction in illegal primate hunting activities following conducting regular anti-poaching patrols, alongside other interventions. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1471https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1471Tue, 17 Oct 2017 14:33:00 +0100Collected Evidence: Collected Evidence: Provide training to anti-poaching ranger patrols One study in Uganda found that no gorillas were killed over 21 months after game guards received training, alongside other interventions. One before-and-after study in Rwanda found that the number of immature gorillas increased in areas where game guards received training, alongside other interventions. One before-and-after study in India found that a population of hoolock gibbons increased after sanctuary staff received training, alongside other interventions. One before-and-after study in Cameroon found that no incidents of primate poaching occurred over a three year period after anti-poaching rangers were trained, alongside other interventions. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1477https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1477Tue, 17 Oct 2017 17:30:03 +0100Collected Evidence: Collected Evidence: Implement local no-hunting community policies/traditional hunting ban One review found that very few snub nosed monkeys were killed annually at a site in China where it is forbidden to kill wildlife. One controlled study in the Democratic Republic of Congo found that a lowland gorilla population increased after the implementation of a local hunting ban. One before-and-after study in Belize found that an introduced black howler monkey population increased over time in an area where hunting was controlled, alongside other interventions. One before-and-after study in Cameroon found that a drill population increased in numbers after being protected by a hunting ban, alongside other interventions. A study in Nigeria found that populations of Sclater’s monkey increased in an area where hunting of the species was prohibited by local taboos. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1478https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1478Tue, 17 Oct 2017 18:40:38 +0100Collected Evidence: Collected Evidence: Implement community control of patrolling, banning hunting and removing snares A site comparison study in the Democratic Republic of Congo found that community control was more effective at reducing illegal bushmeat hunting, including primates, compared to the nearby national park. A before-and-after study in Cameroon found that no incidents of gorilla poaching occurred over three years after implementation of community control and monitoring of illegal activities. A site comparison study in Nigeria found that there were more gorillas and chimpanzees in an area managed by a community conservation organisation than in areas not managed by local communities. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1482https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1482Tue, 17 Oct 2017 19:12:50 +0100Collected Evidence: Collected Evidence: Use selective logging instead of clear-cutting One site comparison in Sierra Leone found that primate densities were higher in forest that had been logged at low intensity than in a forest logged at high intensity. One before-and-after study in Madagascar found that the number of lemurs increased following selective logging. One site comparison study in Uganda found that primate densities were similar in forest that had been logged at low intensity and forest logged at high intensity. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1485https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1485Tue, 17 Oct 2017 19:26:45 +0100Collected Evidence: Collected Evidence: Provide monetary benefits to local communities for sustainably managing their forest and its wildlife (e.g. REDD, employment) One before-and-after study in Belize found that numbers of black howler monkeys increased by 138% over 13 years after local communities received monetary benefits, alongside other interventions. One before-and-after study in the Republic of Congo found that most central chimpanzees reintroduced to an area where local communities received monetary benefits, alongside other interventions, survived over five years. One before-and-after study in Rwanda, Uganda and the Democratic Republic of Congo found that numbers of mountain gorillas declined by 28% over 41 years despite the implementation of development projects in nearby communities, alongside other interventions. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1509https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1509Wed, 18 Oct 2017 15:15:52 +0100Collected Evidence: Collected Evidence: Run research project and ensure permanent human presence at site Two before-and-after studies in Rwanda, Uganda and Congo found that numbers of mountain gorillas increased over 5-41 years while gorillas were continuously monitored by researchers, alongside other interventions. One review on mountain gorillas in Uganda found that no gorilla was killed over one year while gorillas were continuously monitored by researchers, alongside other interventions. One before-and-after study in Brazil found that most reintroduced golden lion tamarins did not survive over seven years post-release despite being permanently monitored by researchers, alongside other interventions, yet tamarins reproduced succesfully. One before-and-after study in Belize found that numbers of black howler monkeys increased by 138% over 13 years after being permanently monitored by researchers, alongside other interventions. One before-and-after study in the Republic of Congo found that most reintroduced chimpanzees permanently monitored by researchers, alongside other interventions, survived over 3.5 years. One before-and-after study in Kenya found ‘problem’ olive baboon troops still survived over 17 years post-translocation while being permanently monitored by researchers, alongside other interventions. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1511https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1511Wed, 18 Oct 2017 15:51:12 +0100Collected Evidence: Collected Evidence: Run tourist projects and ensure permanent human presence at site Three studies, including two before-and-after studies and one controlled study in Rwanda, Uganda and the Republic of Congo found that numbers of mountain gorillas increased after touristic projects were initiated, alongside other interventions. One before-and-after and site comparison study in Rwanda found that the number of immature mountain gorillas increased by 22% and the number of snares declined by 30% after a tourism project was initiated, alongside other interventions. One before-and-after study in Kenya found that numbers of Tana River red colobus and crested mangabeys decreased despite implementing a tourism project, alongside other interventions. One before-and-after study in Belize found that numbers of black howler monkeys increased by 138% over 13 years after a tourism project was implemented, alongside other interventions. One before-and-after, replicated study in China found that implementing an intensive tourism project for Tibetan macaques that included food provisioning and range restrictions, increased their stress levels compared to previous periods, with infant mortality reaching 100% in some years. One before-and-after study in Madagascar found that after implementing a tourism project the population size and/or body size and group size declined for two lemur species but the number of individuals increased for one other lemur species.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1512https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1512Wed, 18 Oct 2017 15:55:18 +0100Collected Evidence: Collected Evidence: Permanent presence of staff/manager One before-and-after study in Kenya found that numbers of Tana River red colobus and crested mangabeys decreased despite permanent presence of reserve staff, alongside other interventions. One study in Thailand found that a reintroduced population of lar gibbons declined over three years despite permanent presence of reserve staff alongside other interventions. One before-and-after study in Belize found that numbers of black howler monkeys increased by 138% over 13 years after introducing permanent presence of reserve staff, alongside other interventions. One before-and-after study in Congo found that most reintroduced central chimpanzees survived over five years after being accompanied by reserve staff, alongside other interventions. One before-and-after study in Gabon found that most reintroduced western lowland gorillas survived over nine months, after being accompanied by reserve staff, alongside other interventions. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1517https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1517Thu, 19 Oct 2017 09:22:48 +0100Collected Evidence: Collected Evidence: Habituate primates to human presence to reduce stress from tourists/researchers etc. A before-and-after study in Brazil found that an introduced population of golden lion tamarins declined after one year, following habituation to human presence, alongside other interventions. A before-and-after study in Madagascar found that the majority of introduced black-and-white ruffed lemurs and diademed sifakas survived over 30 months, following habituation to human presence, alongside other interventions. A controlled, before-and-after study in Rwanda, Uganda, and Democratic Republic of Congo found that a mountain gorilla population increased over 41 years, following habituation to human presence, alongside other interventions. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1519https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1519Thu, 19 Oct 2017 09:30:50 +0100Collected Evidence: Collected Evidence: Implement legal protection for primate species under threat A before-and-after study in India found that following a ban on export of the species, a population of rhesus macaques increased over 17 years. Two studies in Thailand and India found that primate populations declined despite the respective species being legally protected, alongside other interventions. One before-and-after study in Malaysia found that the majority of introduced Müller's Bornean gibbons died despite legal protection, along with other interventions. A site comparison of five sites in Cameroon found that drill populations declined in four sites but increased at one, despite legal protection. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1524https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1524Thu, 19 Oct 2017 09:39:16 +0100Collected Evidence: Collected Evidence: Regularly and continuously provide supplementary food to primates Two studies in China and The Gambia found that after regularly providing supplementary food, along with other interventions, primate populations increased. Two studies in Thailand and Malaysia found that populations declined after regular provision of supplementary food, alongside other interventions. Three studies in Brazil, South Africa, and Indonesia found that the majority of primates survived after being regularly provided supplementary food, along with other interventions. One study in Liberia found that after regular provision of supplementary food, along with other interventions, the majority of introduced chimpanzees survived for at least one year. One controlled study in Madagascar found that after a year of regular food supplimentation, along with other interventions, introduced black-and-white ruffed lemurs showed different diets compared to a resident wild group of the same species. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1526https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1526Thu, 19 Oct 2017 09:53:52 +0100Collected Evidence: Collected Evidence: Regularly provide supplementary food to primates during resource scarce periods only One before-and-after study in the Republic of Congo found that the majority of chimpanzees survived for at least five years after supplementary feeding in resource scarce periods, alongside other interventions. One before-and-after study in Kenya found that wild olive baboons survived for at least 17 years after supplementary feeding in drought periods soon after translocation, alongside other interventions. One controlled study in Madagascar found that the diet of black-and-white ruffed lemurs was similar to that of wild individuals after supplementary feeding in resource scarce periods, alongside other interventions. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1527https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1527Thu, 19 Oct 2017 09:59:24 +0100Collected Evidence: Collected Evidence: Provide additional sleeping platforms/nesting sites for primates One before-and-after study in Brazil found that a translocated lion tamarin population declined after artificial nest boxes were provided, alongside other interventions. One before-and-after study in Brazil found that a majority of reintroduced golden lion tamarins died seven years after artificial nest boxes were provided, alongside other interventions. One before-and-after study in Gabon found that a majority of juvenile western lowland gorillas survived for at least seven years after nesting platforms were provided, alongside other interventions. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1530https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1530Thu, 19 Oct 2017 10:22:21 +0100Collected Evidence: Collected Evidence: Provide artificial water sources One before-and-after trial in Brazil found that a minority of reintroduced golden lion tamarins survived over seven years when provided with supplementary water, alongside other interventions. One before-and-after study in Madagascar found that a minority of reintroduced black-and-white ruffed lemurs survived for five years despite being provided with supplementary water, alongside other interventions. A before-and-after study in South Africa found that a minority of vervet monkeys had survived for 10 months when provided with supplementary water, alongside other interventions. A before-and-after study in Gabon found that a majority of western lowland gorillas survived for at least nine months while being provided with supplementary water, alongside other interventions. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1531https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1531Thu, 19 Oct 2017 10:26:56 +0100Collected Evidence: Collected Evidence: Keep safety distance to habituated animals One before-and-after study in the Democratic Republic of Congo found that most reintroduced chimpanzees survived over five years after being followed from a distance of 5–100 m, alongside other interventions. One controlled study in Malaysia found that the number of reintroduced orangutans declined by 33% over 31 years despite visitors being required to keep a safety distance to the animals, alongside other interventions. One before-and-after study in Rwanda, Uganda and Congo found that numbers of mountain gorillas increased by 168% over 41 years while being observed from a safety distance, alongside other interventions. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1538https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1538Thu, 19 Oct 2017 14:38:23 +0100Collected Evidence: Collected Evidence: Preventative vaccination of habituated or wild primates One before-and-after study in Puerto Rico found that annual mortality of rhesus macaques decreased after a preventive tetanus vaccine campaign, alongside other interventions. Two before-and-after studies in the Republic of Congo found that 70% of reintroduced chimpanzees vaccinated against poliomyelitis and tetanus, alongside other interventions, survived over 3.5-5 years after release. One before-and-after study in the Republic of Congo and Gabon found that more than 80% of the reintroduced gorillas that received preventive vaccination, alongside other interventions, survived over a 10 year period. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1549https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1549Thu, 19 Oct 2017 17:45:11 +0100Collected Evidence: Collected Evidence: Detect & report dead primates and clinically determine their cause of death to avoid disease transmission One before-and-after study in the Republic of Congo found that most reintroduced chimpanzees survived over five years when dead chimpanzees were examined to determine their cause of death, alongside other interventions. One before-and-after study in French Guiana found that most translocated white-faced sakis survived over four months when dead sakis were examined to determine their cause of death, alongside other interventions. One before-and-after study in Madagascar found that most black-and-white ruffed lemurs did not survive over five years despite the fact that dead lemurs were clinically examined to determine their cause of death, alongside other interventions. One controlled, before-and-after study in Rwanda, Uganda and the Democratic Republic of Congo found that the population size of mountain gorillas where dead animals were examined to determine the cause of death, alongside other interventions, increased by 168% over 41 years. One before-and-after, site comparison study in Congo and Gabon found that most western lowland gorillas survived over four years when dead individuals were examined to determine their cause of death, alongside other interventions. Two studies, including a before-and-after, in Vietnam and Indonesia found that most reintroduced pygmy slow lorises either died or disappeared despite the fact that dead lorises were examined to determine their cause of death, alongside other interventions. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1556https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1556Thu, 19 Oct 2017 20:58:29 +0100Collected Evidence: Collected Evidence: Translocate (capture & release) wild primates from development sites to natural habitat elsewhere One study in Malaysia found that the majority of orangutans survived following translocation from a development site to natural habitat, alongside other interventions. Three before-and-after studies in Tanzania, French Guiana, and Madagascar found that a majority of primates survived for 5-30 months following translocation from a development site to natural habitat, alongside other interventions. One study in French Guiana found that a minority of primates survived for at least 18 months. One before-and-after study in India found that rhesus monkeys remained at the sites where they were released following translocation from a development site to natural habitat, alongside other interventions. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1558https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1558Fri, 20 Oct 2017 09:44:55 +0100Collected Evidence: Collected Evidence: Involve local community in primate research and conservation management One before-and-after study in Uganda found that a reintroduced chimpanzee repeatedly returned to human settlements despite the involvement of local communities in the reintroduction project, alongside other interventions. One before-and-after study in Belize found that numbers of black howler monkeys increased over 13 years while local communities were involved in the management of the sanctuary, alongside other interventions. One before-and-after study in Rwanda, Uganda and the Democratic Republic of Congo found that mountain gorilla numbers decreased over 41 years despite the implementation of an environmental education programme, alongside other interventions. One before-and-after study in Cameroon found that incidents of gorilla poaching stopped after the implementation of a community-based monitoring scheme, alongside other interventions. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1565https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1565Fri, 20 Oct 2017 10:26:50 +0100Collected Evidence: Collected Evidence: Implement multimedia campaigns using theatre, film, print media, discussions Two before-and-after studies in Belize found that black howler monkey numbers increased by 61-138% over 3–13 years after the implementation of a multimedia campaign or the opening of a museum for wildlife education, alongside other interventions. Two before-and-after studies in Brazil and Colombia found that the implementation of education programs focusing on tamarins improved attitudes towards- and knowledge about tamarins. One study in the Republic of Congo found that large numbers of people were informed about lowland gorillas through multimedia campaigns using theatre and film. One before-and-after study in Madagascar found that poaching of diademed sifakas and black and white ruffed lemurs appeared to have ceased after the distribution of conservation books in local primary schools. One before-and-after study in India found that numbers of hoolock gibbons increased by 66% over five years after the implementation of an education and awareness programme, alongside other interventions. One before-and-after study in four African countries found that the level of knowledge about primates of visitors to a sanctuary housing guenons, mangabeys, chimpanzees and bonobos increased after the implementation of an education programme. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1571https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1571Fri, 20 Oct 2017 11:45:16 +0100Collected Evidence: Collected Evidence: Legally protect primate habitat A review on the status of rhesus monkeys and grey snub-monkeys in China found that primate numbers increased or no more individuals were killed after the area was legally protected, alongside other interventions. One before-and-after study in Kenya found that Tana River red colobus monkey and crested mangabey numbers decreased despite the area being declared legally protected, alongside other interventions. One before-and-after study in China found that Hainan gibbon numbers increased by 34% over nine years after the area was declared legally protected. One before-and-after study in Brazil found that most golden lion tamarins did not survive over seven years despite being reintroduced to a legally protected area, alongside other interventions yet they reproduced and surviving offspring partly compensated adult mortality. Two before-and-after studies in the Republic of Congo and Gabon found that most central chimpanzees and lowland gorillas reintroduced to areas that received legal protection, alongside other interventions, survived over 4–5 years. One controlled, site comparison study in Mexico found that black howler monkeys in protected areas had lower stress levels than individuals living in unprotected forest fragments. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1578https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1578Fri, 20 Oct 2017 12:49:30 +0100Collected Evidence: Collected Evidence: Captive breeding and reintroduction of primates into the wild: born and reared in cages One before-and-after study in Brazil found that most reintroduced golden lion tamarins that were born and reared in cages, alongside other interventions, did not survive over seven years or had a higher mortality than wild-born tamarins. One controlled study in French Guiana found that more squirrel monkeys which were born and reared in cages, alongside other interventions, died or were returned to captivity post-reintroduction compared to wild-born monkeys. One controlled study in Madagascar found that the diet of reintroduced black-and-white ruffed lemurs which were born and reared in cages, alongside other interventions, did not overlap with that of wild lemurs. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1594https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1594Fri, 20 Oct 2017 14:33:22 +0100Collected Evidence: Collected Evidence: Captive breeding and reintroduction of primates into the wild: limited free-ranging experience One controlled study in Madagascar found that the diet of reintroduced black-and-white ruffed lemurs with limited free-ranging experience, alongside other interventions, overlapped with that of wild lemurs. One before-and-after study in Madagascar found that most reintroduced black-and-white ruffed lemurs with limited free-ranging experience, alongside other interventions, died over five years. One before-and-after and site comparison and one before-and-after study in the Republic of Congo and Gabon found that most reintroduced western lowland gorillas with limited free-ranging experience, alongside other interventions, survived over a period of between nine months and four years. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1595https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1595Fri, 20 Oct 2017 14:36:52 +0100Collected Evidence: Collected Evidence: Fostering appropriate behaviour to facilitate rehabilitation Two before-and-after studies in Brazil found that most reintroduced golden lion tamarins did not survive over 1–7 years, despite being fostered to survive in the wild, alongside other interventions but in one study they reproduced successfully which partly compensated mortality. Two before-and-after studies in Liberia and Congo found that most reintroduced chimpanzees that were fostered to facilitate reintroduction, alongside other interventions, survived over 1-3.5 years. One before-and-after study in Uganda found that a reintroduced chimpanzee repeatedly returned to human settlements despite being fostered to facilitate reintroduction, alongside other interventions. One controlled study in Indonesia found that reintroduced orangutans that were fostered natural behaviour, alongside other interventions, did not act more like wild orangutans than individuals that were not fostered. One study in Indonesia found that reintroduced orangutans that were fostered to facilitate reintroduction, alongside other interventions, fed on fewer plant species and spent more time building nests. One site comparison study in Vietnam found that all reintroduced pygmy slow lorises were assumed dead despite being fostered natural behaviour prior to release, alongside other interventions. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1600https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1600Fri, 20 Oct 2017 15:00:07 +0100
What Works 2021 cover

What Works in Conservation

What Works in Conservation provides expert assessments of the effectiveness of actions, based on summarised evidence, in synopses. Subjects covered so far include amphibians, birds, mammals, forests, peatland and control of freshwater invasive species. More are in progress.

More about What Works in Conservation

Download free PDF or purchase
The Conservation Evidence Journal

The Conservation Evidence Journal

An online, free to publish in, open-access journal publishing results from research and projects that test the effectiveness of conservation actions.

Read the latest volume: Volume 21

Go to the CE Journal

Discover more on our blog

Our blog contains the latest news and updates from the Conservation Evidence team, the Conservation Evidence Journal, and our global partners in evidence-based conservation.

Who uses Conservation Evidence?

Meet some of the evidence champions

Endangered Landscape ProgrammeRed List Champion - Arc Kent Wildlife Trust The Rufford Foundation Save the Frogs - Ghana Mauritian Wildlife Supporting Conservation Leaders
Sustainability Dashboard National Biodiversity Network Frog Life The international journey of Conservation - Oryx Cool Farm Alliance UNEP AWFA Bat Conservation InternationalPeople trust for endangered species Vincet Wildlife Trust
For a full list of, and information about, our champions:
All Evidence Champions
About our champions, why and how to become one:
Become an Evidence Champion

This website uses Cookies

We use limited Cookies to run the site and to analyse our traffic (none for site vendors). By using this site, you will be providing your consent to our use of Cookies.

Accept & continue