Collected 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: 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: Mechanically remove understory vegetation to reduce wildfires We found no evidence for the effects of mechanically removing understory vegetation to reduce wildfires. '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%2F1219https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1219Fri, 20 May 2016 14:42:38 +0100Collected Evidence: Collected Evidence: Mechanically/manually remove invasive plants One replicated, controlled study in Hawaii found that removal of invasive grass species increased understory plant biomass. One replicated, controlled study in the USA found no effect of invasive shrub removal on understory plant diversity. One replicated, controlled study in Ghana found that removal of invasive weed species increased tree seedling height. One replicated, controlled study in Hawaii found no effect of invasive plant removal on growth rate of native species. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1228https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1228Mon, 23 May 2016 10:45:49 +0100Collected Evidence: Collected Evidence: Mechanically remove understory vegetation after tree planting Five studies (including three replicated, randomized, controlled studies) in Canada, the USA, France, Panama and Sweden found no effect of controlling understory vegetation on the emergence, survival, growth rate or frost damage in planted seedlings. However, one found removing competing herbs increased seedling biomass. One replicated, controlled study in Canada found that removal of sheep laurel shrubs increased the growth rate and height of planted black spruce seedlings.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1256https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1256Mon, 06 Jun 2016 09:06:01 +0100Collected Evidence: Collected Evidence: Minimize ground vibrations caused by open cast mining activities We found no evidence for the effects of minimizing ground vibrations caused by open cast mining activities 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%2F1451https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1451Tue, 17 Oct 2017 12:53:24 +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: Minimize road lighting to reduce insect attraction We found no studies that evaluated the effects of minimizing road lighting to reduce insect attraction 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%2F1969https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1969Tue, 04 Dec 2018 18:13:16 +0000Collected Evidence: Collected Evidence: Minimize alterations to caves for tourism We found no studies that evaluated the effects of minimizing alterations to caves for tourism 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%2F1993https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1993Wed, 05 Dec 2018 12:48:48 +0000Collected Evidence: Collected Evidence: Minimize noise levels within caves One study evaluated the effects of minimizing noise levels within caves on bat populations. The study was in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (1 STUDY) Behaviour change (1 study): One controlled study in the USA found that experimental cave tours with groups that did not talk resulted in fewer bat flights than when groups did talk, but talking did not have an effect on the number of bat movements. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1995https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1995Wed, 05 Dec 2018 12:52:09 +0000Collected Evidence: Collected Evidence: Modify a bottom trawl to raise parts of the gear off the seabed during fishing Two studies examined the effects of modifying a bottom trawl to raise parts of the gear off the seabed during fishing on marine fish populations. One study was in the Gulf of Carpentaria (Australia) and one was in the Atlantic Ocean (USA).  COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (2 STUDIES) Reduction of unwanted catch (2 studies): Two replicated studies (one randomized and both controlled) in the Gulf of Carpentaria and the Atlantic Ocean found that bottom trawls with parts of the gear raised off the seabed caught fewer unwanted sharks, other elasmobranchs and fish and fewer of three of seven unwanted fish species compared to conventional trawls. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2708https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2708Mon, 28 Dec 2020 15:51:05 +0000Collected Evidence: Collected Evidence: Minimize food waste at aquaculture systems We found no studies that evaluated the effects of minimizing food waste at aquaculture systems 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%2F2744https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2744Tue, 02 Feb 2021 16:41:13 +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: Minimize road lighting to reduce insect attraction We found no studies that evaluated the effects on butterflies and moths of minimizing road lighting to reduce insect attraction. ‘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%2F3852https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3852Tue, 05 Jul 2022 11:34:54 +0100Collected 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: 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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