Collected Evidence: Collected Evidence: Regulate water levels Two studies (including one replicated, site comparison study) in the UK found that habitat management that included maintaining pond water levels increased natterjack toad populations or maintained newt populations. One replicated, controlled study in Brazil found that keeping rice fields flooded after harvest changed amphibian species composition, but not numbers of species or abundance. One replicated, controlled study in the USA found that draining ponds, particularly in the summer, significantly increased abundance and numbers of amphibian species. One before-and-after study in the USA found that maintaining pond water levels enabled successful breeding by dusky gopher frogs.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F833https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F833Wed, 28 Aug 2013 15:19:57 +0100Collected Evidence: Collected Evidence: Regularly remove traps and snares around agricultural fields We found no evidence for the effects of regularly removing traps and snares around agricultural fields 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%2F1433https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1433Tue, 17 Oct 2017 10:17:41 +0100Collected Evidence: Collected Evidence: Regularly de-activate/remove ground snares One before-and-after study in the Democratic Republic of Congo and Rwanda found that mountain gorilla numbers increased over five years in an area that was patrolled for snares, alongside other interventions. One before-and-after study in the Democratic Republic of Congo, Rwanda and Uganda found that a mountain gorilla population declined in an area where snares were removed regularly, alongside other interventions. One before-and-after study in Ghana found that the number of snares declined in an area where they were regularly removed, alongside other interventions. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1475https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1475Tue, 17 Oct 2017 17:15:09 +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: Regularly disinfect clothes, boots etc. One controlled, before-and-after study in Rwanda, Uganda and Congo found that numbers of mountain gorillas increased by 168% over 41 years while being visited by researchers and tourists whose clothes were disinfected, alongside other interventions. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1547https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1547Thu, 19 Oct 2017 17:33:18 +0100Collected Evidence: Collected Evidence: Regularly play TV & radio announcements to raise primate conservation awareness One before-and-after study in the Republic of Congo found that most reintroduced central chimpanzees whose release was broadcasted by multiple media means, alongside other interventions, survived over five years post-reintroduction. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1569https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1569Fri, 20 Oct 2017 11:42:52 +0100Collected Evidence: Collected Evidence: Regularly clean bat boxes to increase occupancy We found no studies that evaluated the effects of regularly cleaning artificial bat roosts to increase occupancy on bat populations. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated 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%2F2038https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2038Wed, 05 Dec 2018 18:31:05 +0000Collected Evidence: Collected Evidence: Rehabilitate injured/orphaned bats to maintain wild bat populations Four studies evaluated the effects of rehabilitating injured/orphaned bats on bat populations. Two studies were in the UK, one was in Italy and one in Brazil. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (4 STUDIES) Survival (4 studies): One study in Brazil found that two hand-reared orphaned greater spear-nosed bats survived for over three months in captivity. Two studies in the UK and Italy found that 70–90% of hand-reared pipistrelle bats survived for at least 4–14 days after release into the wild, and six of 21 bats joined wild bat colonies. One study in the UK found that pipistrelle bats that flew in a large flight cage for long periods before release survived for longer and were more active than bats that flew for short periods or in a small enclosure. One study in the UK found that 13% of ringed hand-reared pipstrelle bats were found alive in bat boxes 38 days to almost four years after release into the wild. Condition (1 study): One study in Brazil found that two orphaned greater spear-nosed bats increased in body weight and size after being hand-reared, and reached a normal size for the species after 60 days. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2054https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2054Fri, 07 Dec 2018 19:33:05 +0000Collected Evidence: Collected Evidence: Regulate the use, dosage and disposal of agrichemicals We found no studies that evaluated the effects of regulating the use, dosage and disposal of agrichemicals on subtidal benthic invertebrate populations.   ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this intervention during our systematic journal and report searches. Therefore, we have no evidence to indicate whether or not the intervention has any desirable or harmful effects.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2198https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2198Tue, 22 Oct 2019 13:09:55 +0100Collected Evidence: Collected Evidence: Refill disused borrow pits One study examined the effects of refilling disused borrow pits on subtidal benthic invertebrate populations. The study was in Barnegat Bay estuary (USA).   COMMUNITY RESPONSE (1 STUDY) Overall richness/diversity (1 study): One before-and-after, site comparison study in Barnegat Bay estuary found that overall invertebrate species richness and diversity increased at a disused borrow pit after being refilled with sediments but remained lower than at a natural non-dredged site. POPULATION RESPONSE (1 STUDY) Overall abundance (1 study): One before-and-after, site comparison study in Barnegat Bay estuary found that overall invertebrate abundance increased at a disused borrow pit after being refilled with sediments but remained lower than at a natural non-dredged site. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2251https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2251Wed, 23 Oct 2019 09:51:36 +0100Collected Evidence: Collected Evidence: Rehabilitate injured, sick or weak mammals Thirteen studies evaluated the effects of rehabilitating injured, sick or weak mammals. Four studies were in the UK, three were in Spain, two were in Argentina and one each was in Uganda, Australia, the USA and Brazil. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (12 STUDIES) Survival (11 studies): Five studies, in the UK and Spain, found that varying proportions of European hedgehogs released after being rehabilitated in captivity survived during post-release monitoring periods, which ranged from two weeks to 136 days. Five studies, in Australia, Spain, the USA and Brazil, found that four koalas, an Iberian lynx, a gray wolf, a puma and two brown bears released following rehabilitation in captivity survived for varying durations during monitoring periods, which ranged in length from three months to up to seven years. A study in Argentina found that over half of released rehabilitated and captive-reared giant anteaters survived for at least six months. Condition (2 studies): A study in Uganda found that a snare wound in a white rhinoceros healed after treatment and rehabilitation. A study in the UK found that two of three rehabilitated European hedgehogs lost 12-36% of their body weight after release into the wild. BEHAVIOUR (1 STUDY) Behaviour change (1 study): A controlled study in Argentina found that released wild-born rehabilitated giant anteaters were more nocturnal in their activity patterns than captive-bred individuals.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2352https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2352Tue, 26 May 2020 08:46:51 +0100Collected Evidence: Collected Evidence: Rehabilitate and release marine and freshwater mammals following oil spills We found no studies that evaluated the effects of rehabilitating and releasing marine and freshwater mammals following oil spills. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated 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%2F2871https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2871Mon, 08 Feb 2021 11:30:30 +0000Collected Evidence: Collected Evidence: Rehabilitate and release injured, sick or weak marine and freshwater mammals Twenty-seven studies evaluated the effects of rehabilitating and releasing injured, sick or weak marine and freshwater mammals. Nine studies were in the North Atlantic Ocean (USA, UK, France), six studies were in the North Pacific Ocean (USA), four studies were in the Gulf of Mexico (USA), two studies were in each of the North Sea (the Netherlands) and the Gulf of Maine (USA), and one study was in each of the Indian River Lagoon (USA), Bohai Bay (China), The Wash estuary (UK), water bodies in Florida (USA), El Dorado Lake (Peru), and the Gulf of California (Mexico). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (26 STUDIES) Reproductive success (1 study): One replicated study in the North Pacific Ocean found that more than a quarter of rehabilitated and released Hawaiian monk seals reproduced. Survival (26 studies): Twenty-one studies (including two controlled studies, four replicated studies and one review) in the North Atlantic Ocean, the Gulf of Maine, the Gulf of Mexico, the North Pacific Ocean, the Indian River Lagoon, The Wash estuary, water bodies in Florida, El Dorado Lake, and the Gulf of California found that 10–100% of dolphins, porpoises, whales, seals, sea lions and manatees released after rehabilitation in captivity survived during post-release monitoring periods, which ranged in length from three days to five years. Five studies (including one replicated study) in the North Sea, the North Atlantic Ocean, Bohai Bay and the North Pacific Ocean found that two of three harbour porpoises, 152 of 188 grey seal pups, a common seal, a west Pacific finless porpoise and 14 of 35 California sea lions were successfully rehabilitated and released but survival after release was not reported. One controlled study in the North Pacific Ocean found that at least a quarter of California sea lions treated for toxic algae poisoning and released back into the wild died or had to be euthanized. BEHAVIOUR (3 STUDIES) Behaviour change (3 studies): Two of three controlled studies in the North Atlantic Ocean, the North Pacific Ocean and The Wash estuary found that a harbour porpoise and six harbour seals that were rehabilitated and released had similar movements and/or behaviours to wild mammals. The other study found that California sea lions treated for toxic algae poisoning and released travelled further from the shore, spent less time diving or hauled out and made shorter, shallower dives than wild sea lions without poisoning. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2925https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2925Mon, 08 Feb 2021 16:57:11 +0000Collected Evidence: Collected Evidence: Regulate farming to allow gradual regeneration of marshes or swampsWe found no studies that evaluated the effects, on marsh/swamp vegetation, of regulating farming to allow gradual habitat regeneration.   ‘We found no studies’ means that we have not yet found any studies that have directly evaluated 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%2F2951https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2951Mon, 22 Mar 2021 13:40:41 +0000Collected Evidence: Collected Evidence: Regulate temperature of water discharged from power plants One study evaluated the effects of regulating temperature of water discharged from power plants. This study was in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (1 STUDY) Use (1 study): One study in the USA reported that power plant water cooling canals were occupied by a population of American crocodiles. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3495https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3495Mon, 06 Dec 2021 12:12:00 +0000Collected Evidence: Collected Evidence: Regulate wildlife harvesting Four studies evaluated the effects of regulating wildlife harvesting on reptile populations. One study was in each of Costa Rica, Australia, Indonesia and Japan. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Abundance (2 studies): One before-and-after study in Australia found that following legal protection and harvest regulations, the density of saltwater crocodile populations increased. One before-and-after study in Japan found that following regulation of the green turtle harvest in combination with allowing harvested turtles to lay eggs prior to being killed, the number of nesting females tended to be higher. Reproductive success (1 study): One before-and-after study in Japan found that following regulation of the green turtle harvest in combination with allowing harvested turtles to lay eggs prior to being killed, the number of hatchlings produced in natural nests tended to be higher. Condition (1 study): One before-and-after study in Australia found that following legal protection and harvest regulations, the average size of crocodiles increased. BEHAVIOUR (0 STUDIES) OTHER (2 STUDIES) Human behaviour change (2 studies): One replicated study in Costa Rica found that in an area with a legalized turtle egg harvest run by a community cooperative, a majority of people reported a willingness to do more to protect sea turtles. One study in Indonesia reported that quotas to regulate wildlife harvesting did not limit the number of individuals of three reptile species that were harvested and exported. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3538https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3538Tue, 07 Dec 2021 16:33:38 +0000Collected Evidence: Collected Evidence: Regulate planning permission for gas/filling stations at reptile sites We found no studies that evaluated the effects on reptile populations of regulating planning permission for gas/filling stations at reptile sites. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated 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%2F3579https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3579Wed, 08 Dec 2021 15:24:55 +0000Collected Evidence: Collected Evidence: Regulate artificial lighting during vulnerable periods We found no studies that evaluated the effects on reptile populations of regulating artificial lighting during vulnerable periods. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated 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%2F3596https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3596Wed, 08 Dec 2021 16:27:08 +0000Collected Evidence: Collected Evidence: Regulate water levels One study evaluated the effects of regulating water levels on reptile populations. This study was in France. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): One controlled, before-and-after study in France found that autumn–spring marsh flooding with moderate levels of grazing in autumn–winter led to higher numbers of European pond turtles than winter–spring flooding with high levels of grazing in spring–summer. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3660https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3660Fri, 10 Dec 2021 10:51:46 +0000Collected Evidence: Collected Evidence: Rehabilitate and release injured or accidentally caught individuals: Sea turtles Four studies evaluated the effects of rehabilitating and releasing injured or accidentally caught sea turtles on their populations. Two studies were in the USA and one was in each of the Philippines and the western Mediterranean. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (4 STUDIES) Survival (4 studies): One study in the Philippines and one controlled study in the western Mediterranean found that of 79 rehabilitated sea turtles two were found dead and two alive within 1–5 months of release, and six rehabilitated loggerhead turtles survived for at least five months following release. Two studies in the USA found that around one third of stranded sea turtles and 96% of sea turtles caught in fishing gear could be rehabilitated and released. One study also found that the chance of surviving the rehabilitation process varied with species. BEHAVIOUR (1 STUDY) Behaviour change (1 study): One replicated, controlled study in the western Mediterranean found that six rehabilitated loggerhead turtles showed similar behaviour to wild caught turtles across 46 of 54 comparisons. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3740https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3740Tue, 14 Dec 2021 10:23:55 +0000Collected Evidence: Collected Evidence: Rehabilitate and release injured or accidentally caught individuals: Tortoises, terrapins, side-necked & softshell turtles Four studies evaluated the effects of rehabilitating and releasing injured or accidentally caught tortoises, terrapins, side-necked and softshell turtles on their populations. Two studies were in France and one was in each of South Africa and the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (4 STUDIES) Reproductive success (1 study): One controlled study in France found that some rehabilitated Hermann’s tortoises were observed mating with resident tortoises following release. Survival (4 studies): One controlled, before-and-after study in France found that survival of rehabilitated and released Hermann’s tortoises was similar compared to wild tortoises over a two-year period. Three studies (including two replicated studies) in South Africa, France and the USA found that Babcock’s leopard tortoises, Herman’s tortoises and ornate box turtles released following rehabilitation survived for varying durations during monitoring periods that ranged from three months to 25 months or until the end of the active season during the year of release. BEHAVIOUR (2 STUDIES) Behaviour change (2 studies): One controlled study in France found that 12 rehabilitated Herman’s tortoises remained within 2 km of their release site over a three-month period. This study also found that daily movement of rehabilitated and released tortoises was similar to residents. One controlled, before-and-after study in France found that rehabilitated tortoises released in autumn took longer to establish a home range than those released in spring. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3741https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3741Tue, 14 Dec 2021 10:34:25 +0000Collected Evidence: Collected Evidence: Rehabilitate and release injured or accidentally caught individuals: Snakes & lizards We found no studies that evaluated the effects of rehabilitating and releasing injured or accidentally caught snakes and lizards on their populations. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated 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%2F3742https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3742Tue, 14 Dec 2021 10:44:54 +0000Collected Evidence: Collected Evidence: Rehabilitate and release injured or accidentally caught individuals: Crocodilians One study evaluated the effects of rehabilitating and releasing injured or accidentally caught crocodilians on their populations. This study was in India. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Reproductive success (1 study): One study in India found that found that breeding occurred in a rehabilitated and released population of mugger crocodiles four years after the first release. Survival (1 study): One study in India found that seven of eight rehabilitated and released mugger crocodiles survived for at least 1–4 years after release. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3743https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3743Tue, 14 Dec 2021 10:48:01 +0000Collected Evidence: Collected Evidence: Rehabilitate and release injured or accidentally caught individuals: Tuatara We found no studies that evaluated the effects of rehabilitating and releasing injured or accidentally caught tuatara on their populations. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated 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%2F3744https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3744Tue, 14 Dec 2021 11:10:19 +0000
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.

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