Collected Evidence: Collected Evidence: Pay farmers to cover the costs of bird conservation measures Three reviews from the UK of three studies captured reported population increases of three species after the introduction of specially-designed agri-environment schemes. These species were cirl buntings, corncrakes and Eurasian thick-knees. One of these found that many other species continued to decline. Twenty-two of 25 studies all from Europe, including a systematic review,  examining local population levels or densities found that at least some birds studied were at higher densities, had higher population levels or more positive population trends on sites with agri-environment schemes, compared to non-agri-environment scheme sites. Some studies found that differences were present in all seasons, others in either summer or winter. Fifteen studies from Europe, including a systematic review, found that some or all species were not found at higher densities, had similar or lower population levels, showed similar population trends on sites with agri-environment schemes, compared with non-agri-environment scheme sites, or showed negative population trends. A study from the Netherlands found that many agri-environment scheme farms were sited in areas where they were unlikely to be effective. One small study from the UK found no differences between winter densities of seed-eating birds on UK Higher Levels Stewardship sites, compared with those under Entry Level Stewardship. A replicated study from the UK found that grey partridge survival was higher on agri-environment scheme sites than non-scheme sites. This difference was not significant every year. Two of three studies investigating reproductive productivity, including one replicated study, found that productivity was higher on farms under agri-environment schemes. One replicated study from the UK found no effect of agri-environment schemes on productivity. A review (Vickery et al. 2010) found that the amount of land entering an agri-environment scheme was on target, but that some options were not being used at high enough rates to help many species. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F172https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F172Sun, 20 May 2012 14:06:41 +0100Collected Evidence: Collected Evidence: Pay farmers to cover the cost of conservation measures (as in agri-environment schemes) Twenty-six studies from four European countries (including one UK systematic review and three European reviews) looked at the effects of agri-environment schemes on birds. Twenty-four studies (including one systematic review, six site comparisons and nine reviews) found increases in population size, density or more favourable population trends of some or all birds studied on sites with agri-environment schemes compared to non-scheme sites (some of these differences were seasonal). Eleven studies (including one systematic review and four reviews) found negative or no effects. One UK study found higher numbers of some birds where higher tier management was in place, another UK study found no difference between Entry Level or Higher Level Stewardship Scheme fields. One study from the Netherlands found that not all agri-environment scheme agreements were sited in ideal locations for black-tailed godwit. Eleven studies from five European countries (including three replicated paired site comparisons and two reviews) looked at the effects of agri-environment schemes on plants. Seven studies (including three replicated paired site comparisons and one European review) found agri-environment schemes maintained or had little or no effect on plants, plant diversity or species richness. Three studies found increases in plant species richness in areas with agri-environment schemes, two found decreases. A replicated site comparison study from Estonia found higher flower abundance on farms with agri-environment schemes in two out of four areas. A review found Environmentally Sensitive Areas in England had contributed to halting the loss of semi-natural grassland habitats but were less effective at enhancing or restoring grassland biodiversity. Ten studies from three European countries (including two replicated paired site comparisons and a review) looked at the effects of agri-environment schemes on invertebrates. Six studies (including two replicated site comparisons) showed agri-environment schemes maintained or had little or no effect on some invertebrates in terms of diversity, abundance, species richness or bee colony growth. Five studies found increases in abundance or species richness of some invertebrates. A UK study found agri-environment scheme prescriptions had a local but not a landscape-scale effect on bee numbers. Four studies (including two replicated site comparisons and a review) from the UK looked at the effects of agri-environment schemes on mammals. One study found positive effects, three studies found mixed effects in different regions or for different species. Three of the studies above found higher numbers of wildlife on land before agri-environment schemes were introduced. However two studies collecting baseline data found no difference in the overall number of birds or earthworms and soil microorganisms between areas with and without agri-environment schemes. A review found two out of three agri-environment schemes in Europe benefited wildlife. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F700https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F700Fri, 21 Dec 2012 14:38:13 +0000Collected Evidence: Collected Evidence: Pay farmers to cover the costs of conservation measures Three studies (including one replicated study) in Denmark, Sweden and Taiwan found that payments to farmers created amphibian breeding habitat or increased frog or toad populations. However, a second study in Taiwan found that payments did not maintain green tree frog habitat. One replicated, site comparison study in the Netherlands found that ditches managed under agri-environment schemes had higher numbers of amphibian species and higher abundance than those managed conventionally.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F818https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F818Fri, 23 Aug 2013 09:47:58 +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: Use of lightproof barriers We found no evidence on the use of lightproof barriers 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%2F1576https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1576Fri, 20 Oct 2017 12:32:56 +0100Collected Evidence: Collected Evidence: Parrot’s feather: Water level drawdown One replicated, randomized, controlled laboratory study in the USA found that water removal to expose plants to drying during the summer led to lower survival of parrot’s feather plants than exposing plants to drying during the winter. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1585https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1585Fri, 20 Oct 2017 13:07:37 +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 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 salt We found no evidence on the impact of using salt 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%2F1605https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1605Fri, 20 Oct 2017 15:18:45 +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: Use of herbicides - triclopyr Two replicated, controlled laboratory studies in New Zealand and the USA reported reduced growth of parrot’s feather following treatment with triclopyr. One replicated, before-and-after and one replicated, controlled field study in New Zealand found that cover was reduced after treatment with triclopyr. However, one of the studies noted that cover later increased to levels close to pre-treatment. One replicated, controlled laboratory study in New Zealand found that the application of triclopyr led to a greater reduction in cover than the application of glyphosate. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1689https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1689Mon, 23 Oct 2017 10:03:03 +0100Collected Evidence: Collected Evidence: Parrot’s feather: Use of herbicides - other herbicides One replicated, controlled laboratory study in New Zealand found that the application of dichlobenil reduced the growth of parrot’s feather. Two replicated, randomized, controlled field studies in Portugal and New Zealand found that the application of dichlobenil reduced cover less than the combined application of the herbicides 2,4-D and MCPA eight days after treatment but not 45 days after treatment and that plants treated with dichlobenil presented lower vegetation cover soon after herbicide application but cover later increased to levels close to pre-treatment. Three laboratory studies (including two replicated, controlled studies and one randomized, controlled study) in the USA found that the herbicides imazamox and imazapyr reduced the growth of parrot’s feather. One replicated, randomized, controlled field study in Portugal and one replicated, controlled, laboratory study in the USA reported reduced parrot’s feather biomass after treatment with glyphosate. One replicated, randomized, controlled field study in Portugal found that the application of gluphosinate-ammonium reduced the biomass of parrot’s feather. Three replicated, controlled laboratory studies in New Zealand and the USA found that treatment with fluridone, clopyralid and copper chelate did not reduce growth of parrot’s feather. One replicated, controlled laboratory study in the USA found that the application of flumioxazin reduced the growth of parrot’s feather. One replicated, randomized, controlled laboratory study in the USA found that the application of florpyrauxifen-benzyl reduced the growth of parrot’s feather. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1699https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1699Mon, 23 Oct 2017 11:11:47 +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: Pay farmers to compensate for losses due to predators/wild herbivores to reduce human-wildlife conflict Five studies evaluated the effects on mammals of paying farmers compensation for losses due to predators or wild herbivores to reduce human-wildlife conflict. Three studies were in Kenya and one each was in Italy and Sweden. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (5 STUDIES) Abundance (2 studies): Two studies, in Italy and Sweden, found that compensating livestock owners for losses to predators led to increasing populations of wolves and wolverines. Survival (3 studies): Three before-and-after studies (including two replicated studies), in Kenya, found that when pastoralists were compensated for livestock killings by predators, fewer lions were killed. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2414https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2414Fri, 29 May 2020 15:48:47 +0100Collected Evidence: Collected Evidence: Patrol or monitor nesting beaches Seven studies evaluated the effects of patrolling or monitoring nesting beaches on reptile populations. Three studies were in Costa Rica and one was in each of the US Virgin Islands, Mexico, Mozambique and the Dominican Republic. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Reproductive success (2 studies): One before-and-after site comparison study in Costa Rica found that olive ridley turtle nests that were moved to a patrolled hatchery and nests that were camouflaged on the nesting beach had similar hatching success. One replicated, controlled study in the Dominican Republic found that on beaches with regular patrols, hatching success of leatherback turtle nests was higher than in nests relocated to hatcheries. BEHAVIOUR (0 STUDIES) OTHER (6 STUDIES) Human behaviour change (6 studies): Two studies in the US Virgin Islands and Costa Rica found that during years when beach patrols were carried out poaching of leatherback turtle nests decreased. Three studies (including two before-and-after studies) in Costa Rica and Mexico found that when beach patrols were carried out in combination with either an education programme for local communities, limiting beach access or camouflaging nests and moving nests to a hatchery, poaching of leatherback turtle nests and olive ridley turtle nests decreased. One before-and-after study in Mozambique found that during a community-based turtle monitoring project no green turtle egg collection or hunting of adults was recorded. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3541https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3541Tue, 07 Dec 2021 16:56:30 +0000
What Works 2021 cover

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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