Collected Evidence: Collected Evidence: Paint wind turbines to increase their visibilityA single ex situ experiment found that thick black stripes running across a wind turbine’s blades made them more conspicuous to an American kestrel than control (unpatterned) blades, but that other designs were less visible, or indistinguishable from controls.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F258https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F258Wed, 18 Jul 2012 13:40:49 +0100Collected Evidence: Collected Evidence: Other biodiversity: Use organic fertilizer instead of inorganicAmphibians (0 studies) Birds (0 studies) Invertebrates (0 studies) Mammals (0 studies) Plants (1 study): One replicated, randomized, controlled study from Italy found more plants and plant biomass, but similar numbers of plant species, in plots with organic fertilizer, compared to plots with inorganic fertilizer. Reptiles (0 studies) Implementation options (0 studies)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1412https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1412Fri, 19 May 2017 09:46:03 +0100Collected Evidence: Collected Evidence: Other biodiversity: Use fewer grazersAmphibians (0 studies) Birds (0 studies) Invertebrates (1 study): One replicated, randomized, controlled study in wet grasslands in the USA found more families of insects in streams in areas grazed by cattle at lower, compared to higher, intensities. Mammals (0 studies) Plants (11 studies) Abundance (11 studies): Six studies (four replicated, randomized, and controlled) in grasslands or wood pasture in the USA, Chile, and Israel found higher cover of some species of plants, herbaceous plants, or native plants in areas grazed by cattle or sheep at lower, compared to higher, intensities. One controlled study in forest in Israel found higher cover of woody vegetation in areas with lower grazing intensity. Four of these studies also found lower cover or biomass of some groups of plants in sites with lower grazing intensity. Four studies in grasslands in the USA and Israel found no effect of grazing intensity on biomass, cover, or abundance of plants. Diversity (6 studies): Three replicated, randomized, controlled studies in grasslands and wet grasslands in the USA and Israel found no differences in plant diversity between sites with different cattle-grazing intensities, in some or all comparisons. One of these also found higher diversity in some comparisons and lower diversity in others. One replicated, randomized, controlled study in wet grasslands in the USA found that plant community composition differed in sites with different cattle-grazing intensities, in some comparisons. Two replicated, randomized, controlled studies in grasslands and wet grasslands in Israel and the USA found no differences in the number of plant species between sites with different cattle grazing intensities, in some or all comparisons. One of these studies also found more species in some comparisons and fewer species in others. One controlled study in wood pasture in Chile found fewer native species and more non-native species in paddocks with lower sheep-grazing intensities. Survival (3 studies): Three controlled studies (two replicated and randomized) in grasslands in the USA and forests in Israel found no difference in native grass, tree, or shrub survival in areas grazed by cows at lower, compared to higher, intensities. Reptiles (0 studies) Implementation options (0 studies)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1418https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1418Fri, 19 May 2017 11:23:37 +0100Collected Evidence: Collected Evidence: Other biodiversity: Use grazers to manage vegetationAmphibians (0 studies) Birds (1 study): One replicated, randomized, controlled study in grasslands in the USA found higher densities of dabbling duck nests, but similar nesting success, in cattle-grazed plots, compared to ungrazed plots. Invertebrates (4 studies): Two replicated studies (one controlled, one site comparison) in grasslands in the USA and Spain found more invertebrates in sheep-, goat-, or cattle-grazed plots, compared to ungrazed plots, in some or all comparisons. One before-and-after study in grassland in the USA found that a threatened, endemic butterfly species did not recolonize a site after grazing was reintroduced. One replicated, randomized, controlled study in grasslands in the USA found fewer invertebrates in plots with simulated grazing, compared to ungrazed plots, but found similar numbers of invertebrate species. One replicated site comparison in forested grasslands in Spain found higher beetle diversity in grazed plots, compared to ungrazed plots, in one of two beetle groups. Two replicated studies (one randomized and controlled) in grasslands in the USA and Spain found different invertebrate communities in grazed and ungrazed plots. Mammals (2 studies): Two replicated, controlled studies (one randomized before-and-after study) in grasslands in the USA found that abundances of some or all rodents were higher, or increased more, on sheep- or cow-grazed plots, compared to ungrazed plots. However, they also found that some species were less abundant or monthly survival was lower on grazed plots. Plants (15 studies) Abundance (14 studies): Eight studies (two meta-analyses; two replicated, randomized, and controlled) from grasslands, shrublands, and forests in the USA, Spain, and France found higher cover or higher abundance of some groups of plants (or lower cover of undesirable plants), on cattle-, sheep-, or goat-grazed plots, compared to ungrazed plots. Six studies (five replicated; one randomized and controlled) from grasslands in Spain and the USA found lower cover or lower abundance of some groups of plants on cattle-, sheep-, or goat-grazed plots, compared to ungrazed plots (or after grazers were reintroduced). Three replicated, controlled studies (two randomized) from grasslands in the USA found similar cover or biomass on grazed or ungrazed plots. Diversity (7 studies): Three studies (one meta-analysis; two replicated site comparisons) from grasslands in the USA found more plant species on grazed plots, compared to ungrazed plots, in some or all comparisons. One of these studies also found fewer species of some plant groups on grazed plots, and two of these stuides also found more non-native species on grazed plots, compared to ungrazed plots. Two replicated, controlled studies (one randomized) in grasslands in the USA and France found no difference in the number of plant species between cattle- or sheep-grazed plots and ungrazed plots. Two replicated controlled studies (one randomized) from grasslands in the USA and France found no difference in plant diversity between cattle- or sheep-grazed plots and ungrazed plots. One replicated, randomized, controlled study grasslands and woodlands in the USA found that plant community composition varied between cattle-grazed and ungrazed plots. Survival (3 studies): Of two studies on purple needlegrass mortality from grasslands in the USA, one replicated, randomized, controlled study found lower mortality on sheep-grazed plots, compared to ungrazed plots, in some comparisons, but found higher mortality in other comparisons, and one replicated, controlled study found no difference in mortality between cattle-grazed plots and ungrazed plots. One replicated, randomized, controlled study from grasslands in the USA found lower germination rates in purple needlegrass seeds from sheep-grazed plots, compared to ungrazed plots, in some comparisons. Reptiles (1 study): One replicated, controlled study in grasslands in the USA found that the abundance of some lizard species increased at a greater rate on cattle-grazed plots, compared to ungrazed plots. Implementation options (1 study): One study from the USA found more invertebrates on plots with simulated grazing, compared to ungrazed plots, when these plots were planted with non-native plants. One study in shrublands in Spain found lower gorse cover in plots grazed by goats, compared to sheep, as well as other differences in plant biomass and cover.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1419https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1419Fri, 19 May 2017 11:26:09 +0100Collected Evidence: Collected Evidence: Other biodiversity: Use rotational grazingAmphibians (0 studies) Birds (0 studies) Invertebrates (0 studies) Mammals (0 studies) Plants (2 studies): One before-and-after study in grasslands in the USA found a higher cover of native plants after the adoption of rotational grazing. One replicated, controlled study in grasslands in the USA found that the density and mortality of a native plant species did not differ between plots with rotational or continuous grazing, but plants had more reproductive stems in plots with rotational grazing, in two of three years. This study also found that plants were larger under rotational grazing, in some comparisons, but smaller in other comparisons. Reptiles (0 studies) Implementation options (0 studies)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1420https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1420Fri, 19 May 2017 11:31:10 +0100Collected Evidence: Collected Evidence: Other biodiversity: Use seasonal grazingAmphibians (0 studies) Birds (0 studies) Invertebrates (1 study): One replicated, randomized, controlled before-and-after study in wet grasslands in the USA found more aquatic invertebrate species in continuously grazed plots, compared to seasonally grazed plots, in some comparisons. Mammals (0 studies) Plants (8 studies) Abundance (7 studies): Five studies (one meta-analysis; four replicated, randomized, and controlled studies) in grasslands in Israel and the USA found that the cover of native or non-native plants, or the abundance of plants, differed between sites grazed at different times, in some comparisons. Two replicated, randomized, controlled studies from forested pastures in the USA and former farmland in Spain found no difference in plant cover between areas grazed at different times. Diversity (2 studies): Two replicated, randomized, controlled studies in grasslands in Israel and the USA found differences in the number and/or diversity of plant species between plots that were grazed at different times, in some comparisons. Survival (2 studies): One replicated, randomized, controlled study in grasslands in the USA found differences in tree survival between plots grazed at different times. Another one found no difference in bunchgrass survival between plots grazed at different times. Reptiles (0 studies) Implementation options (0 studies)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1421https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1421Fri, 19 May 2017 11:33:49 +0100Collected Evidence: Collected Evidence: Parrot’s feather: Mechanical harvesting and cutting We found no evidence on the use of manual harvesting to control parrot’s feather. '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%2F1568https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1568Fri, 20 Oct 2017 11:31:24 +0100Collected Evidence: Collected Evidence: Parrot’s feather: Mechanical excavation We found no evidence on the use of mechanical excavation to control parrot’s feather. '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%2F1570https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1570Fri, 20 Oct 2017 11:44:58 +0100Collected Evidence: Collected Evidence: Parrot’s feather: Removal using water jets We found no evidence on the use of water jets to control parrot’s feather. '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%2F1572https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1572Fri, 20 Oct 2017 12:26:00 +0100Collected Evidence: Collected Evidence: Parrot’s feather: Suction dredging and diver-assisted suction removal We found no evidence on the use of suction dredging and diver-assisted suction removal to control parrot’s feather. '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%2F1573https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1573Fri, 20 Oct 2017 12:27:56 +0100Collected Evidence: Collected Evidence: Parrot’s feather: Manual harvesting (hand-weeding) We found no evidence on the effects of manual to control parrot’s feather. '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%2F1575https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1575Fri, 20 Oct 2017 12:31:39 +0100Collected Evidence: Collected Evidence: Parrot’s feather: Dye application We found no evidence on the use of dye treatments to control parrot’s feather. '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%2F1587https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1587Fri, 20 Oct 2017 13:10:23 +0100Collected Evidence: Collected Evidence: Parrot’s feather: Biological control using fungal-based herbicides We found no evidence for the effects of biological control of parrot’s feather using fungal-based herbicides. '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%2F1598https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1598Fri, 20 Oct 2017 14:56:08 +0100Collected Evidence: Collected Evidence: Parrot’s feather: Biological control using herbivores One replicated, controlled laboratory study in Portugal found that grass carp did not reduce biomass or cover of parrot’s feather. Two replicated, randomized field studies in Argentina and the USA found that stocking with grass carp reduced the biomass or abundance of parrot’s feather. One field study in South Africa reported reduced growth of parrot’s feather following the release a South American leaf-feeding Lysathia. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1599https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1599Fri, 20 Oct 2017 14:58:11 +0100Collected Evidence: Collected Evidence: Parrot’s feather: Biological control using plant pathogens One study in South Africa found that parrot’s feather plants survived after being treated with a strain of the bacterium Xanthomonas campestris. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1601https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1601Fri, 20 Oct 2017 15:05:32 +0100Collected Evidence: Collected Evidence: Parrot’s feather: Decontamination / preventing further spread We found no evidence on the effects of decontamination to prevent further spread of parrot’s feather. '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%2F1602https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1602Fri, 20 Oct 2017 15:09:30 +0100Collected Evidence: Collected Evidence: Parrot’s feather: Public education We found no evidence on the impact of education programmes on the control of parrot’s feather. '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%2F1603https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1603Fri, 20 Oct 2017 15:11:55 +0100Collected Evidence: Collected Evidence: Parrot’s feather: Reduction of trade through legislation and codes of conduct One randomized, before-and-after trial in the Netherlands reported that the implementation of a code of conduct reduced the trade of aquatic plants banned from sale (group that included parrot’s feather Myriophyllum aquaticum). One study in the USA found that parrot’s feather plants were still traded despite a state-wise trade ban. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1604https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1604Fri, 20 Oct 2017 15:14:50 +0100Collected Evidence: Collected Evidence: Parrot’s feather: Use of herbicides - 2,4-D Three laboratory studies (including two replicated, controlled studies and one randomized, controlled study) in the USA and Brazil found that the herbicide 2,4-D reduced the growth of parrot’s feather. One replicated, controlled laboratory study in Brazil found that 2,4-D led to a greater reduction in growth of parrot’s feather than the herbicides diquat, glyphosate or imazapyr. One replicated, randomized, controlled field study in Portugal found that 2,4-D amine reduced the biomass of parrot’s feather. One randomized, controlled field study in Portugal found that the combined application of 2,4-D and MCPA completely eliminated parrot’s feather. One randomized, controlled laboratory study in the USA found that the combined application of 2,4-D and carfentrazone-ethyl led to a higher reduction in the cover of parrot’s feather than the application of the herbicide dichlobenil eight days after treatment but not 45 days after treatment. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1606https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1606Fri, 20 Oct 2017 16:31:34 +0100Collected Evidence: Collected Evidence: Parrot’s feather: Use of herbicides - carfentrazone-ethyl Five laboratory studies (including one replicated, controlled, before-and-after study) in the USA found that carfentrazone-ethyl reduced growth in parrot’s feather. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1676https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1676Mon, 23 Oct 2017 08:54:36 +0100Collected Evidence: Collected Evidence: Parrot’s feather: Use of herbicides - diquat Two laboratory studies (including a replicated, randomized, controlled study) in the USA found that diquat reduced the growth of parrot’s feather. One replicated, randomized, controlled field study in Portugal found that growth was not reduced after the application of diquat. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1680https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1680Mon, 23 Oct 2017 09:11:46 +0100Collected Evidence: Collected Evidence: Parrot’s feather: Use of herbicides - endohall Two replicated, controlled laboratory studies in New Zealand and the USA found that endothall reduced the growth of parrot’s feather. One replicated, randomized, controlled field study in New Zealand found that parrot’s feather plants treated with endohall presented lower cover soon after herbicide application but cover later increased to levels similar to pre-treatment. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1681https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1681Mon, 23 Oct 2017 09:16:19 +0100Collected Evidence: Collected Evidence: Parrot’s feather: Multiple integrated measures We found no evidence on the use of multiple integrated measures to control parrot’s feather. '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%2F1709https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1709Mon, 23 Oct 2017 13:15:16 +0100Collected Evidence: Collected Evidence: Paint turbines to reduce insect attraction We found no studies that evaluated the effects of painting turbines 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%2F1959https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1959Tue, 04 Dec 2018 15:21:05 +0000Collected Evidence: Collected Evidence: Outfit trawls with a raised footrope We found no studies that evaluated the effects of outfitting trawls with a raised footrope 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%2F2129https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2129Tue, 22 Oct 2019 10:25:27 +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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