Collected Evidence: Collected Evidence: Keep pure breeding populations of native honey bee subspeciesOne replicated trial in Switzerland found that pure breeding populations of the European black honey bee Apis mellifera mellifera contained a significant proportion (28%) of hybrids with an introduced subspecies Apis mellifera carnica.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F43https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F43Thu, 20 May 2010 14:49:31 +0100Collected Evidence: Collected Evidence: Isolate colonies of beneficial antsNatural enemies: One replicated, controlled study from Australia found predatory ants occupied more cashew trees when colonies were kept isolated. Pest damage and yield: The same study found lower pest damage to cashews and higher yields. The crop studied was cashew.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F773https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F773Tue, 20 Aug 2013 15:54:13 +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: 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: Irrigate degraded shrublands One replicated, randomized, controlled study at two sites in USA found that temporary irrigation increased shrub cover. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1696https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1696Mon, 23 Oct 2017 10:52:55 +0100Collected Evidence: Collected Evidence: Irrigate peatland (before/after planting) One study evaluated the effects, on peatland vegetation, of irrigating areas planted with peatland plants. The study was in a bog. Cover (1 study): One replicated, paired, controlled, before-and-after study in a bog in Canada found that irrigation increased the number of Sphagnum moss shoots present 1–2 growing seasons after sowing Sphagnum fragments. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1832https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1832Tue, 28 Nov 2017 08:52:45 +0000Collected Evidence: Collected Evidence: Irrigate peatland (without planting) Two studies evaluated the effects of irrigation (without planting) on peatland vegetation. One study was in a bog and one was in a fen. Vegetation cover (2 studies): One replicated, paired, controlled, before-and-after study in a bog in Canada found that irrigation increased the number of Sphagnum moss shoots present after one growing season, but had no effect after two. One before-and-after study in Germany reported that an irrigated fen was colonized by wetland- and fen-characteristic herbs, whilst cover of dryland grasses decreased. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1859https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1859Mon, 11 Dec 2017 15:05:17 +0000Collected Evidence: Collected Evidence: Keep domestic cats indoors at night We found no studies that evaluated the effects of keeping domestic cats indoors at night 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%2F2003https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2003Wed, 05 Dec 2018 15:28:13 +0000Collected Evidence: Collected Evidence: Leave a fallow period during fish/shellfish farming Three studies examined the effects of leaving a fallow period during fish farming on subtidal benthic invertebrate populations. Two studies were in the Tasman Sea (Australia), and one in the North Pacific Ocean (USA).   COMMUNITY RESPONSE (3 STUDIES) Overall community composition (2 study): Two replicated, before-and-after, site comparison study in the Tasman Sea found that after a fallow period invertebrate community composition became similar to that occurring before the fish were added but remained different to communities at sites without fish farms. Worm community composition (1 study): One replicated, before-and-after, site comparison study in the North Pacific Ocean found that after a fallow period polychaete worm community composition changed but remained different to communities at sites without fish farms. Worm richness/diversity (1 study): One replicated, before-and-after, site comparison study in the North Pacific Ocean found that after a fallow period polychaete worm diversity did not change and remained lower compared to sites without fish farms. POPULATION RESPONSE (2 STUDIES) Worm abundance (2 studies): Two replicated, before-and-after, site comparison studies in the Tasman Sea and the North Pacific Ocean found that following a fallow period, abundances of pollution-indicator polychaete worms decreased, but remained higher compared to sites without fish farms. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2191https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2191Tue, 22 Oct 2019 13:02:17 +0100Collected Evidence: Collected Evidence: Landscape or artificially enhance the seabed (natural habitats) Three studies examined the effects of landscaping or artificially enhancing the seabed on subtidal benthic invertebrates. One study was in the North Sea (UK), one in the Westerschelde estuary (Netherlands), and one in the Persian Gulf (Kuwait).   COMMUNITY RESPONSE (3 STUDIES) Overall community composition (2 studies): One controlled, before-and after study in the North Sea found that following addition of gravels, invertebrate community composition became more similar to natural seabed communities. One before-and-after, site comparison study in the Westerschelde estuary found no change in invertebrate community composition following addition of sedimentary dredge material. Overall richness/diversity (3 studies): One controlled, before-and after study in the North Sea and one site comparison study in the Persian Gulf found that invertebrate species richness increased following addition of gravels or coral and limestone rubbles, and one also found that richness became similar to natural seabed. One before-and-after, site comparison study in the Westerschelde estuary found no change in species richness following addition of sedimentary dredged material. POPULATION RESPONSE (3 STUDIES) Overall abundance (3 studies): One controlled, before-and after study in the North Sea and one site comparison study in the Persian Gulf found that invertebrate abundance and biomass increased following addition of gravels or coral and limestone rubbles, and one also found that abundance became similar to natural seabed. One before-and-after, site comparison study in the Westerschelde estuary found no change in invertebrate abundance and biomass following addition of sedimentary dredge material. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2253https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2253Wed, 23 Oct 2019 09:56:38 +0100Collected Evidence: Collected Evidence: Keep cats indoors or in outside runs to reduce predation of wild mammals One study evaluated the effects on potential prey mammals of keeping cats indoors or in outside runs. This study was in the UK. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Survival (1 study): One replicated study in the UK found that keeping domestic cats indoors at night reduced the number of dead or injured mammals that were brought home. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2326https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2326Thu, 21 May 2020 09:53:43 +0100Collected Evidence: Collected Evidence: Keep dogs indoors or in outside enclosures to reduce threats to wild mammals We found no studies that evaluated the effects on mammals of keeping dogs indoors or in outside enclosures to reduce threats to wild mammals. ‘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%2F2334https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2334Thu, 21 May 2020 13:18:55 +0100Collected Evidence: Collected Evidence: Keep domestic cats and dogs well-fed to reduce predation of wild mammals We found no studies that evaluated the effects on mammals of keeping domestic cats and dogs well-fed to reduce predation of wild mammals. ‘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%2F2335https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2335Thu, 21 May 2020 13:21:00 +0100Collected Evidence: Collected Evidence: Issue enforcement notices to deter use of non bear-proof garbage dumpsters to reduce human-wildlife conflict One study evaluated the effects of issuing enforcement notices to deter use of non bear-proof garbage dumpsters to reduce human-wildlife conflict. This study was in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Human-wildlife conflict (1 study): A replicated, controlled, before-and-after study in the USA found that issuing enforcement notices requiring appropriate dumpster use did not reduce garbage accessibility to black bears. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2345https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2345Fri, 22 May 2020 13:17:38 +0100Collected Evidence: Collected Evidence: Keep livestock in enclosures to reduce predation by mammals to reduce human-wildlife conflict One study evaluated the effects of keeping livestock in enclosures to reduce predation by mammals to reduce human-wildlife conflict. This study was in Portugal. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Human-wildlife conflict (1 study): A replicated study in Portugal found fewer wolf attacks on cattle on farms where cattle were confined for at least some of the time compared to those with free-ranging cattle. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2438https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2438Tue, 02 Jun 2020 09:42:50 +0100Collected Evidence: Collected Evidence: Issue high fines and penalties for non-compliance with fisheries regulations We found no studies that evaluated the effects of issuing high fines and penalties for non-compliance with fisheries regulations on marine fish 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%2F2772https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2772Wed, 03 Feb 2021 11:19:38 +0000Collected Evidence: Collected Evidence: Involve fishers in designing and trialling new gear types to encourage uptake of more selective fishing gear We found no studies that evaluated the effects of involving fishers in designing and trialling new gear types on marine fish 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%2F2810https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2810Fri, 05 Feb 2021 10:02:04 +0000Collected Evidence: Collected Evidence: Involve stakeholders in allocation of harvest rights We found no studies that evaluated the effects of involving stakeholders in the allocation of harvest rights on marine fish 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%2F2812https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2812Fri, 05 Feb 2021 10:07:06 +0000Collected Evidence: Collected Evidence: Involve fishers in designing and trialling new fishing gear types to encourage uptake of gear that reduces unwanted catch of mammals We found no studies that evaluated the effects of involving fishers in designing and trialling new fishing gear types to encourage uptake of gear that reduces unwanted catch of mammals on marine and freshwater mammal 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%2F2833https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2833Fri, 05 Feb 2021 16:06:36 +0000Collected Evidence: Collected Evidence: Involve local communities in marine and freshwater mammal conservation projects We found no studies that evaluated the effects of involving local communities in marine and freshwater mammal conservation projects on marine and freshwater mammal 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%2F2936https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2936Tue, 09 Feb 2021 11:44:18 +0000Collected Evidence: Collected Evidence: Irrigate (before/after planting)We found no studies that evaluated the effects, on vegetation, of irrigating areas planted with emergent marsh/swamp plants.   ‘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%2F3280https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3280Sat, 10 Apr 2021 17:15:17 +0100Collected Evidence: Collected Evidence: Irrigate before or after seeding/planting Two studies examined the effects of irrigating before or after seeding/planting on grasslands. One study was in Spain and one in the USA. VEGETATION COMMUNITY (2 STUDIES) Overall richness/diversity (2 studies): One of two replicated, controlled studies (one of which was randomized and paired) in Spain and the USA found that irrigating after sowing non-native seeds increased plant diversity in four of 10 cases. The other study found that irrigating after sowing native seeds did not alter plant species richness. Native/non-target species richness/diversity (1 study): One replicated, controlled study in the USA found that irrigating after sowing seeds did not alter the species richness of native plants. VEGETATION ABUNDANCE (2 STUDIES) Overall abundance (1 study): One replicated, randomized, paired, controlled study in Spain found that irrigating after sowing non-native seeds increased vegetation cover in six of 10 cases. Native/non-target species abundance (1 study): One replicated, controlled study in the USA found that irrigating after sowing seeds did not alter the cover of native plant species. VEGETATION STRUCTURE (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3430https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3430Mon, 28 Jun 2021 13:31:34 +0100Collected Evidence: Collected Evidence: Involve fishers in designing and trialling new fishing gear types to encourage uptake of gear that reduces unwanted catch of reptiles We found no studies that evaluated the effects on reptile populations of involving fishers in designing and trialling new fishing gear types to encourage uptake of gear that reduces unwanted catch of reptiles. ‘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%2F3617https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3617Thu, 09 Dec 2021 13:27:50 +0000Collected Evidence: Collected Evidence: Keep domestic cats indoors at times when reptiles are most active We found no studies that evaluated the effects on reptile populations of keeping domestic cats indoors at times when reptiles are most active. ‘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%2F3684https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3684Fri, 10 Dec 2021 15:51:52 +0000Collected Evidence: Collected Evidence: Leash or restrict domestic dog movements in reptile habitats We found no studies that evaluated the effects on reptile populations of leashing or restricting domestic dog movements in reptile habitats. ‘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%2F3685https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3685Fri, 10 Dec 2021 16:07:49 +0000
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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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