Collected Evidence: Collected Evidence: Manage wild honey bees sustainablyWe can find no evidence of the impact of reduced honey-hunting or improved harvesting methods on wild honey bee populations. One trial in southern Vietnam, showed that occupancy of artificial rafters by the giant honey bee Apis dorsata can be over 85% when rafters are placed by a large clearing greater than 25 m in diameter.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F32https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F32Thu, 20 May 2010 05:25:33 +0100Collected Evidence: Collected Evidence: Manage wild deer numbers We have captured no evidence for the effects of managing wild deer numbers 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%2F111https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F111Mon, 24 Oct 2011 22:10:17 +0100Collected Evidence: Collected Evidence: Manage woodland edges to benefit widlife We have captured no evidence for the effects of managing woodland edges to benefit wildlife 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%2F140https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F140Fri, 02 Dec 2011 11:19:56 +0000Collected Evidence: Collected Evidence: Mark bird nests during harvest or mowing One replicated study from the Netherlands found that marked northern lapwing nests were less likely to fail as a result of farming operations than unmarked nests.    Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F148https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F148Sat, 14 Jan 2012 14:52:47 +0000Collected Evidence: Collected Evidence: Mark or tint windows to reduce collision mortality Two randomised, replicated and controlled studies (one ex situ) found that marking windows did not appear to reduce bird collisions. However, when windows were largely covered with white cloth, fewer birds flew towards them. A randomised, replicated and controlled study found that fewer birds collided with tinted windows than with un-tinted ones, although the authors noted that the poor reflective quality of the glass could have influenced the results. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F167https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F167Sat, 19 May 2012 20:22:28 +0100Collected Evidence: Collected Evidence: Mark nests during harvestA replicated study from the Netherlands found that northern lapwing Vanellus vanellus nests were less likely to be destroyed when they were marked, compared to when they were not.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F194https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F194Wed, 27 Jun 2012 17:39:00 +0100Collected Evidence: Collected Evidence: Mark fences to reduce bird collision mortalityA randomised, replicated and controlled study from the UK found that fewer birds collided with deer fence marked with orange netting than with unmarked sections.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F238https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F238Wed, 18 Jul 2012 10:34:56 +0100Collected Evidence: Collected Evidence: Mark power lines to reduce incidental bird mortality A total of eight studies and two literature reviews from across the world found that marking power lines led to significant reductions in collision rates or dangerous flight behaviour (i.e. approaching close to power lines) in cranes Grus spp., mute swans Cygnus olor and other bird species. All markers except thin, black plastic strips or neoprene crosses were effective, with no differences in effectiveness between Bird Flight Diverters (BFDs: brightly coloured plastic spirals) and static fibreglass plates and only a small possible difference between BFDs and ‘flappers’ (moving markers).  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F265https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F265Thu, 19 Jul 2012 14:03:03 +0100Collected Evidence: Collected Evidence: Mark eggs to reduce their appeal to egg collectorsA single before-and-after study found that marking eggs greatly increased the number of chicks fledging from six raptor nests in Australia in 1979 and 1980.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F276https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F276Tue, 24 Jul 2012 12:25:58 +0100Collected Evidence: Collected Evidence: Mark trawler warp cables to reduce seabird collisionsA replicated, controlled study in Argentina found that seabird mortality from collisions with trawler warp cables was much lower when the cables were marked.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F305https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F305Tue, 24 Jul 2012 18:15:42 +0100Collected Evidence: Collected Evidence: Manage woodland edges for birds We captured three studies of two experiments, of which one, a before-and-after study from the UK, found an increase in the local population of European nightjars following several management interventions, including the management of woodland edges for birds. Two studies of a replicated, controlled paired sites experiment in the USA found that bird abundances were higher in woodland edges with border-edge cuts and that predation on artificial nests was lower than in uncut edges. Scrub- and edge-nesting species were more abundant. Overall species richness and nest success did not differ different between treatments.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F334https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F334Sat, 28 Jul 2012 14:12:39 +0100Collected Evidence: Collected Evidence: Manually control or remove midstorey and ground-level vegetation (including mowing, chaining, cutting etc) in forests Of fifteen studies captured, one, a replicated controlled study from the USA, found higher bird species richness in areas with midstorey thinning, compared to control areas. One study from the USA found similar bird species richness in areas with mid- and understorey control, compared to other management types. A study from Canada found fewer species in treated sites than controls. Seven studies from Europe and the USA found that total bird densities or those of some species or guilds were higher in areas with mid- or understorey management, compared to before management or to areas without management. Four of these studies used understorey removal as part of a wider management regime. Five studies from the USA and Canada found that densities of some species were lower in areas with midi or understorey control, or that overall bird densities did not different between managed and unmanaged areas. Two of these studies investigated several interventions at once. A replicated controlled study from the USA found similar survival for black-chinned hummingbirds in areas with understorey management, compared to areas with other interventions. Two replicated, controlled studies from Canada found higher nest survival in forests with removal of deciduous trees, compared to controls. A controlled study found that northern bobwhite chicks had greater foraging success in areas with cleared understorey vegetation compared to burned areas, but lower than under other managements. A replicated, controlled study from the USA found that midstorey control did not appear to affect competition between species for nesting sites.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F335https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F335Sat, 28 Jul 2012 14:20:23 +0100Collected Evidence: Collected Evidence: Manually control or remove midstorey and ground-level vegetation (including mowing, chaining, cutting etc) in shrubland Of seven studies, one controlled study from the USA, found that overall bird diversity was similar between chained areas, burned areas and controls. A replicated and controlled study from the USA found that overall diversity was lower on mown sites than  controls, but that grassland-specialist species were present on managed sites. Five studies from the USA and Europe found than some study species were found at greater densities or abundances on sites with mechanical vegetation control than on sites with prescribed burning or  no management, or that abundances increased after management. One study investigated several interventions at once. One study from the USA found that total bird densities were similar between chained, burned and control sites. A replicated controlled study from the USA found that mown sites had lower bird abundances than control sites. Three studies from the USA found that some species were less abundant on sites with mechanical vegetation removal, compared with burned or control sites, or showed smaller increases after management. One replicated, controlled study from the USA found no differences between areas cut in winter and those cut in summer.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F337https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F337Sat, 28 Jul 2012 14:58:09 +0100Collected Evidence: Collected Evidence: Mark fencing to avoid bird mortality We have captured no evidence for the effects of marking fencing to avoid bird mortality 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%2F706https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F706Mon, 11 Feb 2013 09:51:33 +0000Collected Evidence: Collected Evidence: Mechanically remove mid-storey or ground vegetation One randomized, replicated, controlled study in the USA found that numbers of amphibian species, but not abundance, were significantly higher in plots with mechanical understory reduction compared to those without.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F781https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F781Thu, 22 Aug 2013 13:38:07 +0100Collected Evidence: Collected Evidence: Manually/mechanically remove native plants We found no evidence for the effects of manually or mechanically removing native plants 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%2F1197https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1197Thu, 19 May 2016 13:12:38 +0100Collected Evidence: Collected Evidence: Manage woody debris before tree planting One replicated, randomized, controlled study in Canada found that removal of woody debris increased the survival rate of planted trees. One replicated, controlled study in the USA found mixed effects of removing, chopping and burning woody debris on the size of planted trees.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1257https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1257Mon, 06 Jun 2016 09:39:53 +0100Collected Evidence: Collected Evidence: Manually control or remove secondary mid-storey and ground-level vegetation We found no evidence for the effects of manually controlling or removing secondary mid-storey and ground-level vegetation 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%2F1492https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1492Tue, 17 Oct 2017 19:41:16 +0100Collected Evidence: Collected Evidence: Manage wetland water levels for mammal species One study evaluated the effects of managing wetland water levels for mammal species. This study was in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): A replicated, site comparison study in the USA found that managing wetland water levels to be higher in winter increased the abundance of muskrat houses. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2574https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2574Wed, 10 Jun 2020 10:49:37 +0100Collected Evidence: Collected Evidence: Manage water levels and flow in rivers to maintain deep pools and connectivity We found no studies that evaluated the effects of managing water levels and flow in rivers to maintain deep pools and connectivity on 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%2F2914https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2914Mon, 08 Feb 2021 16:24:21 +0000Collected Evidence: Collected Evidence: Manually remove reptiles from roads One study evaluated the effect on reptile populations of manually removing reptiles from roads. This study was in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Survival (1 study): One study in the USA reported that when turtles were being removed from a road following installation of a fence and artificial nesting mounds, fewer turtles were killed on the road than in the year before any interventions began. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3523https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3523Tue, 07 Dec 2021 14:58:50 +0000Collected Evidence: Collected Evidence: Mechanically remove mid-storey or ground vegetation to create fire breaks Two studies evaluated the effects on butterflies and moths of mechanically removing mid-storey or ground vegetation to create fire breaks. One study was in Portugal and the other was in France. COMMUNITY RESPONSE (2 STUDIES) Richness/diversity (2 studies): One replicated, site comparison study in Portugal found that cork oak woodlands with more recent or more regular mechanical clearance of woody understorey vegetation had a greater species richness of butterflies than woodlands cleared less frequently or longer ago. One replicated, paired, controlled study in France reported that shrublands where trees and/or bushes were mechanically cleared to create firebreaks had a similar species richness of butterflies to a shrubland where grazing was used to suppress vegetation. POPULATION RESPONSE (1 STUDY) Abundance (1 study): One replicated, site comparison study in Portugal found that cork oak woodlands with more recent or more regular mechanical clearance of woody understorey vegetation had a higher abundance of butterflies than woodlands cleared less frequently or longer ago. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3881https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3881Thu, 21 Jul 2022 17:04:10 +0100Collected Evidence: Collected Evidence: Manage woodland edges for maximum habitat heterogeneity Two studies evaluated the effects on butterflies and moths of managing woodland edges for maximum habitat heterogeneity. One study was in Belgium and the other was in Finland. COMMUNITY RESPONSE (1 STUDY) Richness/diversity (1 study): One replicated, paired, controlled, before-and-after study in Finland found that two years after felling 5-m-wide woodland edges, and thinning 20-m-wide adjacent forest, the combined species richness of butterflies, diurnal moths and bumblebees was higher than before management or in unmanaged woodland edges. POPULATION RESPONSE (2 STUDIES) Abundance (2 studies): One replicated, site comparison study in Belgium found that scalloped woodland edges had a higher abundance of brown hairstreak eggs than straight woodland edges. One replicated, paired, controlled, before-and-after study in Finland found that two years after felling 5-m-wide woodland edges and thinning 20-m-wide adjacent forest, the abundance of specialist butterflies was higher than before management or on unmanaged woodland edges. BEHAVIOUR (0 STUDIES)  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3942https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3942Sat, 13 Aug 2022 14:57:49 +0100Collected Evidence: Collected Evidence: Manage wetlands or ponds by grazing or cutting to prevent succession Three studies evaluated the effects on butterflies and moths of managing wetlands or ponds by grazing or cutting. Two studies were in the Netherlands and one was in Switzerland. COMMUNITY RESPONSE (1 STUDY) Richness/diversity (1 study): One replicated, site comparison study in Switzerland found that fens managed by mowing had a greater species richness of butterflies than fens managed by cattle grazing. POPULATION RESPONSE (2 STUDIES) Abundance (1 study): One replicated, site comparison study in the Netherlands found that recently cut fens had fewer large copper eggs than uncut fens. Survival (2 studies): Two replicated, site comparison studies in the Netherlands found that large copper caterpillar survival was lower in recently cut fens, and fens cut in autumn or winter, than in uncut fens. BEHAVIOUR (0 STUDIES)  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3950https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3950Sat, 13 Aug 2022 15:22:08 +0100Collected Evidence: Collected Evidence: Mark the location of webs or caterpillars before mowing One study evaluated the effects on butterflies and moths of marking the location of webs or caterpillars before mowing. This study was in Poland. COMMUNITY RESPONSE (0 STUDIES)   POPULATION RESPONSE (1 STUDY) Abundance (1 study): One replicated, before-and-after study in Poland reported that after marsh fritillary caterpillar webs were marked before mowing, the number of webs increased the following year. BEHAVIOUR (0 STUDIES)  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3970https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3970Sun, 14 Aug 2022 10:39:27 +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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