Collected Evidence: Collected Evidence: Plant indigenous fast-growing trees (will not necessarily resemble original community) in clear-cut areas We found no evidence for the effects of planting indigenous fast-growing trees in clear-cut areas on primate populations. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1586https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1586Fri, 20 Oct 2017 13:09:25 +0100Collected Evidence: Collected Evidence: Use weeding to promote regeneration of indigenous tree communities We found no evidence for the effects of using weeding to promote regeneration of indigenous tree communities on primate populations. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1588https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1588Fri, 20 Oct 2017 13:10:24 +0100Collected Evidence: Collected Evidence: Reintroduce primates as single/multiple individuals One study in Tanzania found that a reintroduced population of chimpanzees increased in size after reintroduction as single/multiple individuals, alongside other interventions. One study in Senegal found that an infant chimpanzee was reunited with its mother after reintroduction, alongside other interventions. Two studies in Brazil and Thailand found that populations of reintroduced primates declined after reintroduction as single/multiple individuals, alongside other interventions. Four studies in French Guiana, Indonesia, Malaysia, and Vietnam found that a minority of primates survived after between two months and one year after reintroduction as single/multiple individuals, alongside other interventions. One study in Vietnam found that half of introduced primates survived after two months. One study in Brazil found that an abandoned infant muriqui was reunited with its mother after reintroduction as single/multiple individuals, alongside other interventions. One study in Indonesia found that Bornean agile gibbons had similar behaviour and diet to wild populations after reintroduction as single/multiple individuals, alongside other interventions. One controlled study in Malaysia found that a reintroduced population of orangutans declined in size after reintroduction, alongside other interventions. One study in Malaysia found that 98% of orangutans survived release after reintroduction, alongside other interventions. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1589https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1589Fri, 20 Oct 2017 13:18:43 +0100Collected Evidence: Collected Evidence: Reintroduce primates into habitat where the species is absent One study in The Gambia found that a population of reintroduced chimpanzees increased over 25 years after reintroduction into habitat where the species was absent, alongside other interventions. One controlled study in Indonesia found that all Sumatran orangutans survived for at least three months after reintroduction into habitat where the species was absent, alongside other interventions. One before-and-after study in the Republic of Congo found that a majority of reintroduced gorillas survived for at least four years after reintroduction into habitat where the species was absent, alongside other interventions. One study in Thailand found that a reintroduced population of lar gibbons declined over three years following reintroduction into habitat where the species was absent, alongside other interventions. One study in India found that a population of reintroduced rhesus monkeys persisted for at least four years after reintroduction. Six studies (including four before-and-after studies) in Belize, Gabon, Madagascar, Malaysia, South Africa, and Vietnam found that a majority of primates survived for two to thirty months after reintroduction into habitat where the species was absent, alongside other interventions. Two studies in Malaysia and Vietnam found that a minority of primates survived after between three months and 12 years. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1590https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1590Fri, 20 Oct 2017 13:38:29 +0100Collected Evidence: Collected Evidence: Reintroduce primates into habitat where the species is present Four before-and-after studies in Guinea and the Republic of Congo found that the majority of reintroduced chimpanzees survived for at least one to five years after reintroduction into habitat where the species was present, alongside other interventions. One study in Uganda found that a reintroduced chimpanzee repeatedly returned to human settlements after reintroduction intro habitat where the species was present, alongside other interventions, while a study in Senegal found that a reintroduced chimpanzee was reunited with its mother. One study in Malaysia found that a majority of reintroduced orangutans survived reintroduction intro habitat where the species was present, alongside other interventions. One controlled study in Malaysia found that a reintroduced population of orangutans had declined 33 years after reintroduction into habitat where the species was present, alongside other interventions. One study in Belize found that primate population increased five years after reintroduction into habitat where the species was present, alongside other interventions, while one study in Thailand found that primate population declined post-reintroduction. Six studies in Brazil, French Guiana, Indonesia, Madagascar, and South Africa found that a minority of primates survived for at least fifteen weeks to seven years after reintroduction into habitat where the species was present, alongside other interventions. Five studies in Brazil, French Guiana, Gabon, and South Africa found that a majority of primates survived for at least two months to one year. Two controlled studies in Madagascar and Indonesia found that reintroduced primates had similar diets to individuals in wild populations after reintroduction into habitat where the species was present, alongside other interventions. One controlled study in Indonesia found that reintroduced primates showed similar behaviour to wild individuals after reintroduction into habitat where the species was present, alongside other interventions. One study in Brazil found that a reintroduced muriqui rejoined a wild group after reintroduction into habitat where the species was present, alongside other interventions. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1591https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1591Fri, 20 Oct 2017 13:46:00 +0100Collected Evidence: Collected Evidence: Reintroduce primates into habitat without predators One study in Tanzania found that a population of reintroduced chimpanzees increased over 16 years following reintroduction into habitat without predators. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1592https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1592Fri, 20 Oct 2017 14:15:01 +0100Collected Evidence: Collected Evidence: Reintroduce primates into habitat with predators Two before-and-after studies in Brazil found that most golden lion tamarins reintroduced into habitat with predators, alongside other interventions, did not survive over one to seven years but reproduced succesfully. Three studies, including two before-and-after studies, in the Congo, The Gambia and Guinea, found that most chimpanzees reintroduced into habitat with predators, alongside other interventions, survived over one to five years or increased population numbers. One before-and-after study in Gabon found that most western lowland gorillas reintroduced into habitat with predators, alongside other interventions, survived over nine months. One before-and-after study in Madagascar found that most black-and-white ruffed lemurs reintroduced into habitat with predators did not survive over five years. One study in Madagascar found that all reintroduced lemurs survived over 30 months after being released into habitat with predators, along with other interventions. One study in Gabon found that most mandrills reintroduced into habitat with predators, alongside other interventions, survived over 30 years. Two before-and-after studies in South Africa found that most vervet monkeys reintroduced into habitat with predators, alongside other interventions, survived over six months. Two studies, including one before-and-after study, in Vietnam and Indonesia found that most lorises reintroduced into habitat with predators, alongside other interventions, were assumed dead within approximately one year after being released. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1593https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1593Fri, 20 Oct 2017 14:16:39 +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: Captive breeding and reintroduction of primates into the wild: born and raised in a free-ranging environment One before-and-after study in Brazil found that only two out of three reintroduced black lion tamarins survived over four months, despite being raised in a free-ranging environment, alongside other interventions. One controlled study in Madagascar found that the diet of reintroduced black-and-white ruffed lemurs that were born and raised in a free-ranging environment alongside other interventions, overlapped with that of wild lemurs. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1596https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1596Fri, 20 Oct 2017 14:44:59 +0100Collected Evidence: Collected Evidence: Rehabilitate injured/orphaned primates One before-and-after study in Brazil found that most reintroduced golden lion tamarins did not survive over seven years, despite being rehabilitated, alongside other interventions. Two before-and-after studies in South Africa found that most reintroduced vervet monkeys survived over six months after being rehabilitated before release, alongside other interventions. Two before-and-after studies in the Republic of Congo found that most reintroduced chimpanzees survived over 3.5–5 years after undergoing pre-release rehabilitation, alongside other interventions. One study in The Gambia found that numbers of reintroduced chimpanzees that underwent pre-release rehabilitation, alongside other interventions, increased by 38% over 25 years. One review on bonobos, chimpanzees and gorillas in 13 African countries found that rehabilitated bonobos living in sanctuaries did not reproduce but the reproductive rate of chimpanzees was 14% and of gorillas was 2%. One controlled study in Indonesia found that Bornean agile gibbons that were rehabilitated before release, alongside other interventions, behaved similarly to wild gibbons. One controlled study in Malaysia found that numbers of reintroduced orangutans decreased by 33% over 33 years, despite orangutans being rehabilitated before release. One controlled study in Indonesia found that most translocated orangutans that were rehabilitated before release, along with other interventions, survived over three months. One before-and-after, site comparison study in the Congo and Gabon found that most western lowland gorillas that were rehabilitated before release, alongside other interventions, survived over four years. One before-and-after study in Gabon found that one out of two western lowland gorillas that were reintroduced died despite being rehabilitated, alongside other interventions. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1597https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1597Fri, 20 Oct 2017 14:47:02 +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
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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.

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