Collected Evidence: Collected Evidence: Reduce conflict by deterring birds from taking crops using bird scarers A controlled paired study in the USA found reduced levels of damage to almond orchards when American crow Corvus brachyrhynchos distress calls were broadcast, compared to the previous year. There were no decreases in control orchards. A replicated study in Pakistan found that four pest species were less abundant when reflector ribbons were hung above crops, compared to when ribbons were not used.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F199https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F199Thu, 28 Jun 2012 11:34:06 +0100Collected Evidence: Collected Evidence: Reduce conflict by deterring birds from taking crops using repellentsA replicated, randomised and controlled ex situ study in the USA found that dickcissels Spiza americana consumed less rice if it was treated with two repellents, compared to controls. Two other repellents did not reduce consumption as effectively.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F200https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F200Thu, 28 Jun 2012 11:40:17 +0100Collected Evidence: Collected Evidence: Reduce ‘ghost fishing’ by lost/discarded gear We found no evidence for the effects on seabird bycatch rates or populations of reducing ghost fishing. '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%2F306https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F306Tue, 24 Jul 2012 18:18:01 +0100Collected Evidence: Collected Evidence: Reduce bycatch by employing seasonal or area closures We found no evidence for the effects on seabird populations or bycatch rates of seasonal or area closures. '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%2F307https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F307Tue, 24 Jul 2012 18:19:08 +0100Collected Evidence: Collected Evidence: Reduce competition between species by providing nest boxesA replicated, controlled study from the USA found that providing extra nest boxes did not reduce the rate at which common starlings Sturnus vulgaris usurped northern flickers Colaptes auratus from nests.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F427https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F427Fri, 17 Aug 2012 17:51:50 +0100Collected Evidence: Collected Evidence: Reduce adverse habitat alterations by excluding problematic terrestrial species Three studies from the USA and the UK found higher numbers of certain songbird species and a higher species richness in these groups when deer were excluded from forests. Intermediate canopy-nesting species in the USA and common nightingales Luscinia macrorhynchos in the UK were the species to benefit. A study from Hawaii found mixed effects of grazer exclusion, with some species showing population increases, some declines and other different long- and short-term trends. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F429https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F429Wed, 22 Aug 2012 13:34:54 +0100Collected Evidence: Collected Evidence: Reduce adverse habitat alterations by excluding problematic aquatic speciesA replicated paired study in the USA found that waterbirds preferentially used wetland plots from which grass carp Ctenopharyngodon idella were excluded but moved as these became depleted over the winter.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F430https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F430Wed, 22 Aug 2012 13:58:45 +0100Collected Evidence: Collected Evidence: Reduce chemical inputs in permanent grassland managementA randomised, replicated, controlled study from the UK found that no more foraging birds were attracted to pasture plots with no fertiliser, compared to control plots.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F459https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F459Wed, 29 Aug 2012 14:37:13 +0100Collected Evidence: Collected Evidence: Reduce chemical inputs in grassland management A total of 16 studies (including five reviews) investigated the effects of reducing inputs in permanent grasslands. Six studies from the Netherlands, Switzerland and the UK (including one review and four replicated studies of which one was also controlled and one a randomized and controlled before-and-after trial) found that stopping fertilizer inputs in permanent grassland resulted in an increase in plant species richness, reduced the rate of plant species loss and attracted a higher abundance or species richness of some or all invertebrates studied. One review from the Netherlands found that low fertilizer input grasslands favour common meadow bird species. One review found a study showing that densities of some invertebrates were higher in unfertilized plots compared with those receiving nitrogen inputs. Two replicated, controlled trials from the Czech Republic and the UK (one randomized) found that applying fertilizer to permanent grasslands reduced plant species richness or diversity and that the effects on plant communities were still apparent 16 years after the cessation of fertilizer application. Four studies from Ireland, the Netherlands and the UK (including two replicated trials of which one randomized and one controlled and a review) found that reducing fertilizer inputs on grassland had no clear or rapid effect on plant species richness. A review found no clear effect of reducing fertilizer inputs on the density of soil-dwelling invertebrates. One replicated study found that fertilizer treatment only affected seed production of a small number of meadow plants. One replicated study from the UK found lower invertebrate abundance on plots with reduced fertilizer inputs but the differences were not significant.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F694https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F694Sat, 01 Dec 2012 17:52:25 +0000Collected Evidence: Collected Evidence: Reduce competition from native amphibians One replicated, site comparison study in the UK found that natterjack toad populations did not increase following common toad control.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F821https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F821Fri, 23 Aug 2013 10:51:47 +0100Collected Evidence: Collected Evidence: Red-eared terrapin: Direct removal of adults A replicated field study in Spain found that Aranzadi turtle traps were effective in trapping red-eared terrapins from a river but did not eradicate the population. A study in the British Virgin Islands found that using sein nets to trap adults and juveniles was not successful in eradicating the population.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1055https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1055Tue, 13 Oct 2015 11:56:26 +0100Collected Evidence: Collected Evidence: Red-eared terrapin: Biological control using native predators No evidence was captured on the use of predators to control invasive terrapin 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%2F1056https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1056Tue, 13 Oct 2015 11:58:10 +0100Collected Evidence: Collected Evidence: Red-eared terrapin: Draining invaded waterbodies No evidence was captured on the impact of draining invaded waterbodies on reduction of red-eared terrapin 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%2F1057https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1057Tue, 13 Oct 2015 12:00:49 +0100Collected Evidence: Collected Evidence: Red-eared terrapin: Search and removal using sniffer dogs No evidence was captured on the success of use of sniffer dogs in removing red-eared terrapins. '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%2F1058https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1058Tue, 13 Oct 2015 12:02:19 +0100Collected Evidence: Collected Evidence: Red-eared terrapin: Application of a biocide One replicated, controlled laboratory study in the USA, found that application of glyphosate to the eggs of red-eared terrapins reduced hatching success to 73%, but only at the highest experimental concentration of glyphosate and a surface active agent.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1059https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1059Tue, 13 Oct 2015 12:05:40 +0100Collected Evidence: Collected Evidence: Red-eared terrapin: Public education No evidence was captured on the impact of education programmes on reduction of red-eared terrapin 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%2F1060https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1060Tue, 13 Oct 2015 12:06:51 +0100Collected Evidence: Collected Evidence: Recycle or repurpose fluids used in the drilling process We found no studies that evaluated the effects of recycling or repurposing fluids used in the drilling process 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%2F2069https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2069Mon, 21 Oct 2019 13:51:26 +0100Collected Evidence: Collected Evidence: Reduce and/or eradicate aquaculture escapees in the wild We found no studies that evaluated the effects of reducing and/or eradicating aquaculture escapees in the wild 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%2F2161https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2161Tue, 22 Oct 2019 12:12:10 +0100Collected Evidence: Collected Evidence: Reduce aquaculture stocking densities We found no studies that evaluated the effects of reducing aquaculture stocking densities 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%2F2186https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2186Tue, 22 Oct 2019 12:55:51 +0100Collected Evidence: Collected Evidence: Recover lost fishing gear We found no studies that evaluated the effects of recovering lost fishing gear 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%2F2206https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2206Tue, 22 Oct 2019 13:16:34 +0100Collected Evidence: Collected Evidence: Reduce capacity of cooling water intake structures We found no studies that evaluated the effects of reducing capacity of cooling water intake structures 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%2F2752https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2752Tue, 02 Feb 2021 16:54:58 +0000Collected Evidence: Collected Evidence: Recover lost or discarded fishing gear We found no studies that evaluated the effects of recovering lost or discarded fishing gear 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%2F2886https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2886Mon, 08 Feb 2021 11:49:11 +0000Collected Evidence: Collected Evidence: Recover lost or discarded fishing gear We found no studies that evaluated the effects on reptile populations of recovering lost or discarded fishing gear. ‘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%2F3567https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3567Wed, 08 Dec 2021 15:04:44 +0000Collected Evidence: Collected Evidence: Reduce cumulative heating effects of urban development by planting vegetation We found no studies that evaluated the effects of reducing the cumulative heating effects of urban development by planting vegetation on reptile 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%2F3648https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3648Thu, 09 Dec 2021 15:49:09 +0000Collected Evidence: Collected Evidence: Reduce cutting frequency on grassland Six studies evaluated the effects on butterflies and moths of reducing cutting frequency on grassland. One study was in each of Slovakia, the Czech Republic, Hungary, the UK, Germany and Italy. COMMUNITY RESPONSE (3 STUDIES) Richness/diversity (3 studies): Two of three replicated studies (including one randomized, paired, controlled study and two site comparison studies) in the UK, Germany and Italy found that meadows cut once/year had a higher species richness of butterflies (along with other pollinators) and moths than meadows cut two or more times/year. The other study found that meadows cut one, two or three times/year all had a similar species richness of butterflies. POPULATION RESPONSE (5 STUDIES) Abundance (5 studies): Three of five replicated studies (including two randomized, paired, controlled studies and three site comparison studies) in Slovakia, the Czech Republic, Hungary, the UK and Italy and found that meadows cut once/year had a similar abundance of all butterflies, and of meadow brown adults and caterpillars and scarce large blue adults, to meadows cut two or three times/year. The other two studies found that meadows cut occasionally or once/year had a higher abundance of Scotch argus and pollinators (including butterflies) than intensively mown grasslands and meadows cut twice/year. BEHAVIOUR (0 STUDIES)  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3961https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3961Sun, 14 Aug 2022 10:37:38 +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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