Collected Evidence: Collected Evidence: Provide grass strips at field margins for beesThree replicated controlled trials in the UK have monitored wild bees on uncropped grassy field margins. Evidence of the effects on bees is mixed. One trial showed that 6 m wide grassy field margins enhanced the abundance, but not diversity, of wild bees at the field boundary. One trial showed that 6 m wide grassy field margins enhanced the abundance and diversity of bumblebees within the margin. A third, smaller scale trial showed neither abundance nor diversity of bumblebees was higher on sown grassy margins than on cropped margins.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F14https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F14Thu, 20 May 2010 10:42:47 +0100Collected Evidence: Collected Evidence: Provide foraging perches (eg. for shrikes) We have captured no evidence for the effects of providing foraging perches (eg. for shrikes) on farmland wildlife. '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%2F79https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F79Mon, 24 Oct 2011 21:12:45 +0100Collected Evidence: Collected Evidence: Provide nest boxes for bees (solitary bees or bumblebees) Ten studies (nine replicated trials and a review of studies) from Germany, Poland and the UK of solitary bee nest boxes all showed the nest boxes were readily used by bees. Two replicated studies found the local population size or number of emerging red mason bees increased when nest boxes were provided. One replicated trial in Germany showed that the number of occupied solitary bee nests almost doubled over three years with repeated nest box provision at a given site. Two replicated trials tested bumblebee nest boxes and both found very low uptake, 2% or less. Occupancy rates of solitary bee nest boxes, where reported (two replicated studies), were between 1 and 26% of available cavities. Five studies (four replicated trials and a review of studies) report the number of bee species found in the nest boxes – between 4.6 and 33 species. One replicated study from Germany found nest boxes should be placed 150-600 m from forage resources (Gathmann & Tscharntke 2002). A replicated study from Poland found the highest production of red mason bees per nest was from nesting materials of reed stems or wood. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F80https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F80Mon, 24 Oct 2011 21:15:42 +0100Collected Evidence: Collected Evidence: Provide medicated grit for grouse A controlled study in England found that red grouse had higher productivity in areas where medicated grit was provided. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F112https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F112Mon, 24 Oct 2011 22:12:09 +0100Collected Evidence: Collected Evidence: Provide food for vultures to reduce mortality from diclofenacA before-and-after trial in Pakistan found that oriental white-backed vulture Gyps bengalensis mortality rates were significantly lower when supplementary food was provided, compared to when it was not.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F456https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F456Wed, 29 Aug 2012 14:30:48 +0100Collected Evidence: Collected Evidence: Provide education programmes about amphibians One study in Taiwan found that education programmes about wetlands and amphibians, along with other interventions, doubled a population of Taipei frogs. Three studies (including one replicated study) in Germany, Mexico, Zimbabwe and the USA found that education programmes increased the amphibian knowledge of students, boatmen and their tourists. Two studies (including one replicated study) in Germany and Slovenia found that students who were taught using live amphibians and had previous direct experience, or who participated in outdoor amphibian conservation work, gained greater knowledge, had improved attitudes towards species and retained knowledge better than those than those taught indoors with pictures. Four studies in Mexico, Taiwan, Zimbabwe and the USA found that courses on amphibians and the environment were attended by 119–6,000 participants and amphibian camps by 700 school children.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F776https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F776Wed, 21 Aug 2013 11:04:07 +0100Collected Evidence: Collected Evidence: Provide education programmes about forests We found no evidence for the effect of providing education programmes about forests on forests. '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%2F1158https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1158Wed, 18 May 2016 15:35:55 +0100Collected Evidence: Collected Evidence: Provide legal protection of forests from development We found no evidence for the effects of providing legal protection of forests from development. '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%2F1169https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1169Thu, 19 May 2016 09:37:01 +0100Collected Evidence: Collected Evidence: Provide financial incentives not to graze We found no evidence for the effects of providing financial incentives not to graze on forests. '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%2F1177https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1177Thu, 19 May 2016 10:30:27 +0100Collected Evidence: Collected Evidence: Provide fuel efficient stoves We found no evidence for the effects of providing fuel efficient stoves on forests. '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%2F1183https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1183Thu, 19 May 2016 10:41:54 +0100Collected Evidence: Collected Evidence: Provide medicine to local communities to control killing of primates for medicinal purposes We found no evidence for the effects of providing medicine to local communities to control the killing of primates for medicinal purposes 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%2F1472https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1472Tue, 17 Oct 2017 14:33:00 +0100Collected Evidence: Collected Evidence: Provide domestic meat to workers of the logging company to reduce hunting We found no evidence for the effects of providing domestic meat to workers of the logging company to reduce hunting 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%2F1501https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1501Tue, 17 Oct 2017 19:56:33 +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: Provide education programmes about shrublands We found no studies that evaluated the effects of providing education programmes on shrublands. '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%2F1718https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1718Mon, 23 Oct 2017 14:03:12 +0100Collected Evidence: Collected Evidence: Provide education or training programmes about peatlands or peatland management Two studies evaluated the effects of peatland education/training programmes on knowledge, behaviour, peatland habitats or peatland vegetation. Both studies were in tropical peat swamps. Behaviour change (2 studies): One study in peat swamps in Indonesia reported that over 3,500 households adopted sustainable farming practices following workshops about sustainable farming. One before-and-after study in peat swamps in Indonesia reported that a training course on rubber farming increased the quality of rubber produced by local farmers. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1848https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1848Tue, 28 Nov 2017 08:58:47 +0000Collected Evidence: Collected Evidence: Provide educational or other training programmes about the marine environment to improve behaviours towards marine invertebrates One study examined the effects of providing educational or other training programmes about the marine environment on subtidal benthic invertebrate populations. The study took place in Hong Kong.   COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (1 STUDY) Behaviour change (1 study): One replicated, before-and-after survey study in Hong Kong found that a conservation education programme on the Asian horseshoe crab in secondary schools significantly increased the students’ behaviour towards Asian horseshoe crab conservation. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2281https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2281Wed, 23 Oct 2019 13:38:47 +0100Collected Evidence: Collected Evidence: Provide education programmes to improve behaviour towards mammals and reduce threats Two studies evaluated the effects of providing education programmes to improve behaviour towards mammals and reduce threats. One study was in South Africa and one was in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): A before-and-after study in South Africa found that educating ranchers on ways of reducing livestock losses, along with stricter hunting policies, increased leopard density. Survival (1 study): A before-and-after study in South Africa found that educating ranchers on ways of reducing livestock losses, along with stricter hunting policies, reduced leopard mortalities. BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Human behaviour change (1 study): A replicated, controlled, before-and-after study in the USA found that visiting households to educate about the danger of garbage to black bears did not increase use of wildlife-resistant dumpsters. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2423https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2423Mon, 01 Jun 2020 14:28:50 +0100Collected Evidence: Collected Evidence: Provide diversionary feeding to reduce predation of livestock by mammals to reduce human-wildlife conflict Two studies evaluated the effects of providing diversionary feeding to reduce predation of livestock by mammals to reduce human-wildlife conflict. One study was in the USA and one was in Canada. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Reproductive success (1 study): A controlled study in the USA found that diversionary feeding of predators did not increase overall nest success rates for ducks. BEHAVIOUR (0 STUDIES) OTHER (2 STUDIES) Human-wildlife conflict (2 studies): One of two studies (one controlled, one before-and-after study) in the USA and Canada found that diversionary feeding reduced striped skunk predation on duck nests. The other study found that diversionary feeding of grizzly bears did not reduce predation on livestock. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2437https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2437Tue, 02 Jun 2020 09:36:08 +0100Collected Evidence: Collected Evidence: Provide live natural prey to captive mammals to foster hunting behaviour before release Three studies evaluated the effects of providing live natural prey to captive mammals to foster hunting behaviour before release. One study was in Spain, one was in the USA and one was in Botswana. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Survival (2 studies): Two studies in Spain and Botswana found that a rehabilitated Iberian lynx and wild-born but captive-reared orphaned cheetahs and leopards that were provided with live natural prey in captivity survived for between at least three months and 19 months after release. BEHAVIOUR (1 STUDY) Behaviour change (1 study): A controlled study in the USA found that captive-bred black-footed ferrets fed on live prairie dogs took longer to disperse after release but showed greater subsequent movements than did ferrets not fed with live prairie dogs. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2518https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2518Mon, 08 Jun 2020 09:14:03 +0100Collected Evidence: Collected Evidence: Provide more small artificial breeding sites rather than fewer large sites One study evaluated the effects on mammals of providing more small artificial breeding sites rather than fewer larger sites. This study was in Spain. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): A replicated, controlled study in Spain found that smaller artificial warrens supported higher rabbit densities than did larger artificial warrens. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2595https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2595Thu, 11 Jun 2020 14:54:25 +0100Collected Evidence: Collected Evidence: Provide food/salt lick to divert mammals from roads or railways Three studies evaluated the effects of providing food or salt licks to divert mammals from roads. One study was in the USA, one was in Norway and one was a review of studies from across North America and Europe. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Survival (2 studies): A replicated, controlled study in the USA found that intercept feeding reduced mule deer road deaths along two of three highways in one of two years. A replicated, site comparison study in Norway found that intercept feeding reduced moose collisions with trains. BEHAVIOUR (1 STUDY) Behaviour change (1 study): A review of feeding wild ungulates in North America, and Europe found that feeding diverted ungulates away from roads in one of three studies. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2617https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2617Fri, 12 Jun 2020 09:14:13 +0100Collected Evidence: Collected Evidence: Provide mammals with escape routes from canals Five studies evaluated the effects on mammals of providing mammals with escape routes from canals. Two studies were in Germany and one each was in the USA, the Netherlands and Argentina. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Survival (2 studies): One of two studies (one before-and-after), in Germany and the USA, found that ramps and ladders reduced mule deer drownings whilst the other study found that ramps and shallow-water inlets did not reduce mammal drownings. BEHAVIOUR (3 STUDIES) Use (3 studies): Three studies (one replicated) in Germany, the Netherlands and Argentina, found that ramps and other access or escape routes out of water were used by a range of medium-sized and large mammals species. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2638https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2638Fri, 12 Jun 2020 13:06:54 +0100Collected Evidence: Collected Evidence: Provide educational materials at marinas and ports to encourage vessel operators to carry out safe practices around mammals (e.g. signs, leaflets) We found no studies that evaluated the effects of providing educational materials at marinas and ports to encourage vessel operators to carry out safe practices around mammals. ‘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%2F2760https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2760Tue, 02 Feb 2021 17:04:29 +0000Collected Evidence: Collected Evidence: Provide general protection for marshes or swamps Three studies evaluated the overall effects, on vegetation or human behaviour, of providing general protection for marshes or swamps. There was one study in each of Puerto Rico, China and Canada. VEGETATION COMMUNITY Overall extent (3 studies): Two studies in China and Canada reported that the area of wetlands (including habitats other than marshes or swamps) in their study regions declined over 10–29 years, despite general protection of wetlands. However, in China, the decline was slower than in a previous period without protection. One before-and-after study of mangrove forests in Puerto Rico reported that their area increased following legal protection. VEGETATION ABUNDANCE   VEGETATION STRUCTURE Overall structure (1 study): One before-and-after study in China reported degradation in wetland landscape structure over 29 years when wetlands were generally protected. However, the decline was slower than in a previous period when wetlands were not protected. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3385https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3385Mon, 12 Apr 2021 09:30:20 +0100Collected Evidence: Collected Evidence: Provide education/training programmes about marshes or swamps Two studies evaluated the effects, on vegetation or human behaviour, of providing education/training programmes related to marshes or swamps. One study was in Kenya and one was in Vietnam. VEGETATION COMMUNITY   VEGETATION ABUNDANCE   VEGETATION STRUCTURE   OTHER Human behaviour (2 studies): One study in Kenya reported that after a series of seminars and workshops about marsh conservation, two community-based management groups were established by local stakeholders and a grazing fee was introduced. One before-and-after study in Vietnam reported that after local people were trained to make more complex handicrafts from marsh plants (along with helping them to sell those handicrafts in markets), their income increased. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3391https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3391Mon, 12 Apr 2021 11:55:44 +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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