Collected Evidence: Collected Evidence: Reduce pesticide or herbicide use generallyOne replicated trial in the USA showed that numbers of foraging bees on squash farms are not affected by the responsible use of pesticides.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F27https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F27Thu, 20 May 2010 19:22:20 +0100Collected Evidence: Collected Evidence: Reduce management intensity on permanent grasslands (several interventions at once) A total of 32 individual studies from the Czech Republic, Germany, Ireland, the Netherlands, Switzerland and the UK looked at the effects on farmland wildlife of reducing management intensity on permanent grasslands. Twenty-two studies found benefits to some or all wildlife groups studied. Eleven studies (including four replicated site comparisons and three reviews) found reduced management intensity on permanent grassland benefited plants. Sixteen studies (including eight site comparisons of which four paired and three reviews) found benefits to some or all invertebrates. Five studies (including two replicated site comparisons, of which one paired, and a review) found positive effects on some or all birds. Twenty-one studies from six European countries found no clear effects of reducing management intensity on some or all plants, invertebrates or birds. Seven studies (including two replicated paired site comparisons and a review) found no clear effect on plants. Ten studies (including four site comparisons and one paired site comparison) found mixed or no effects on some or all invertebrates. Two studies (one review, one site comparison) found invertebrate communities on less intensively managed grasslands were distinct from those on intensively managed grasslands. Four studies (including three site comparisons, of which one paired and two replicated) found no clear effects on bird numbers or species richness. Five studies from four European countries found negative effects of reducing management intensity on plants, invertebrates or birds. Two studies (one review, one replicated trial) found some plant species were lost under extensive management. Two studies (one paired site comparison) found more invertebrates in grasslands with intensive management. One paired site comparison found fewer wading birds on grasslands with reduced management intensity than on conventionally managed grassland.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F69https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F69Mon, 24 Oct 2011 19:11:58 +0100Collected Evidence: Collected Evidence: Reduce management intensity on permanent grasslands for birds Four replicated trials and a review, of seven studies in total, found that some or all birds monitored were more abundant or foraged more on grasslands with lower management intensity than on conventionally managed agricultural grasslands. Four analyses from three replicated trials, of seven studies in total, found that some or all birds monitored were less or similarly abundant on grasslands with lower management intensity than on conventionally managed agricultural grasslands.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F219https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F219Tue, 17 Jul 2012 12:37:47 +0100Collected Evidence: Collected Evidence: Reduce predation by translocating predatorsTwo studies from France and the USA found local population increases or reduced predationfollowing the translocation of predators away from an area.  A study in Saudi Arabia found that predation was no lower when predators were translocated from the bird release site.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F393https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F393Thu, 09 Aug 2012 13:39:34 +0100Collected Evidence: Collected Evidence: Reduce nest predation by excluding predators from nests or nesting areasA 2011 systematic review found that excluding predators from nests significantly increased hatching success, although individual barriers around nests sometimes had adverse impacts. See also: Physically protect nests from predators using non-electric fencing; Physically protect nests with individual exclosures/barriers or provide shelters for chicks; Protect bird nests using electric fencing; Use artificial nests that discourage predation; Guard nests to prevent predation; Plant nesting cover to reduce nest predation; Protect nests from ants; Use multiple barriers to protect nests; Use naphthalene to deter mammalian predators; Use snakeskin to deter mammalian nest predators; Play spoken-word radio programs to deter predators; Use 'cat curfews' to reduce predation; Use lion dung to deter domestic cats; Use mirrors to deter nest predators; Use ultrasonic devices to deter cats; Can nest protection increase nest abandonment?; and Can nest protection increase predation of adults and chicks?Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F396https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F396Thu, 09 Aug 2012 14:28:57 +0100Collected Evidence: Collected Evidence: Reduce predation by translocating nest boxesTwo studies from Europe found that predation rates were lower for relocated nest boxes, compared to controls.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F420https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F420Fri, 17 Aug 2012 16:18:38 +0100Collected Evidence: Collected Evidence: Reduce nest ectoparasites by providing beneficial nesting materialA randomised, replicated and controlled experiment in Canada found lower numbers of some, but not all, parasites in nests provided with beneficial nesting material, but that there was no effect on fledging rates or chick condition.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F439https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F439Thu, 23 Aug 2012 14:26:34 +0100Collected Evidence: Collected Evidence: Reduce pesticide or herbicide use generally A single small study from the UK investigated population level effects of reduced chemical inputs, and found that the populations of some species increased when pesticide use was restricted alongside other interventions. Three studies, two replicated, one controlled, from the UK found that some or all species were found at higher densities on sites with reduced pesticide inputs, in one case with other interventions as well. Five studies from the UK, four replicated, four controlled, found that some or all species were not found at higher densities on fields or sites with reduced chemical inputs, or were not associated with reduced inputs. A controlled before-and-after study from the UK found that grey partridge Perdix perdix chicks had higher survival on sites with reduced pesticide applications. A replicated study from the UK found that reduced chemical inputs had a negative relationship with partridge brood size and no relationship with survival or the ratio of young to old birds.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F454https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F454Wed, 29 Aug 2012 14:08:01 +0100Collected Evidence: Collected Evidence: Reduce pesticide, herbicide or fertilizer use One study in Taiwan found that halting pesticide use along with habitat management increased a population of Taipei frogs.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F832https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F832Wed, 28 Aug 2013 15:16:38 +0100Collected Evidence: Collected Evidence: Reduce road widths We found no evidence for the effects of reducing road widths 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%2F1459https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1459Tue, 17 Oct 2017 13:35:36 +0100Collected Evidence: Collected Evidence: Reduce primate predation by other primate species through exclusion (e.g. fences) or translocation We found no evidence for the effects of reducing primate predation by other primate species through exclusion or translocation 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%2F1522https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1522Thu, 19 Oct 2017 09:32:37 +0100Collected Evidence: Collected Evidence: Reduce primate predation by non-primate species through exclusion (e.g. fences) or translocation We found no evidence for the effects of reducing primate predation by other non-primate species through exclusion or translocation 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%2F1534https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1534Thu, 19 Oct 2017 13:37:57 +0100Collected Evidence: Collected Evidence: Reduce noise pollution by restricting development activities to certain times of the day/night We found no evidence for the effects of reducing noise pollution by restricting development activities to certain times of the day/night 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%2F1562https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1562Fri, 20 Oct 2017 10:05:33 +0100Collected Evidence: Collected Evidence: Reduce number of livestock Two before-and-after trials in the UK and South Africa and one replicated, controlled study in the UK found that the reducing or stopping grazing increased the abundance or cover of shrubs. Two site comparison studies in the UK found that cover of common heather declined in sites with high livestock density, but increased in sites with low livestock density. One site comparison study in the Netherlands found that dwarf shrub cover was higher in ungrazed sites. One replicated, randomized, before-and-after study in Spain found that reducing grazing increased the cover of western gorse. One randomized, controlled trial and one before-and-after trial in the USA found that stopping grazing did not increase shrub abundance. One site comparison study in France found that ungrazed sites had higher cover of ericaceous shrubs, but lower cover of non-ericaceous shrubs than grazed sites. One site comparison study in the UK found that reducing grazing had mixed effects on shrub cover. One replicated, randomized, controlled study in the UK found that reducing grazing increased vegetation height. However, one replicated, controlled, paired site, site comparison study in the UK found that reducing grazing led to a reduction in the height of heather plants. Two site comparison studies in France and the Netherlands found that ungrazed sites had a lower number of plant species than grazed sites. One replicated, controlled, paired, site comparison study in Namibia and South Africa found that reducing livestock numbers increased plant cover and the number of plant species. One controlled study in Israel found that reducing grazing increased plant biomass. However, one randomized, site comparison on the island of Gomera, Spain found that reducing grazing did not increase plant cover and one replicated, controlled study in the UK found that the number of plant species did not change . One replicated, controlled study in the UK found no change in the cover of rush or herbaceous species as a result of a reduction in grazing. Two site comparison studies in France and the Netherlands found that grass cover and sedge cover were lower in ungrazed sites than in grazed sites. One randomized, controlled study in the USA found a mixed effect of reducing grazing on grass cover. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1607https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1607Sun, 22 Oct 2017 09:51:03 +0100Collected Evidence: Collected Evidence: Reduce numbers of large herbivores One before-and-after trial in the USA found that removing feral sheep, cattle and horses increased shrub cover and reduced grass cover. One replicated study in the UK found that reducing grazing pressure by red deer increased the cover and height of common heather. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1663https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1663Sun, 22 Oct 2017 15:06:18 +0100Collected Evidence: Collected Evidence: Reduce pesticide use on nearby agricultural/forestry land We found no studies that evaluated the effects of reducing pesticide use on nearby agricultural/forestry land on shrublands. '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%2F1666https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1666Sun, 22 Oct 2017 15:12:29 +0100Collected Evidence: Collected Evidence: Reduce or prevent the use of septic systems near caves We found no studies that evaluated the effects of reducing or preventing the use of septic systems near caves 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%2F2011https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2011Wed, 05 Dec 2018 16:28:27 +0000Collected Evidence: Collected Evidence: Reduce pesticide, herbicide or fertiliser use Four studies evaluated the effects of reducing pesticide, herbicide and fertiliser use on bat populations. One study was in each of Mexico, Portugal, Germany and Columbia. COMMUNITY RESPONSE (3 STUDIES) Community composition (1 study): One replicated, site comparison study in Portugal found that farms using few or no chemicals had different compositions of bat species to farms using high chemical inputs. Richness/diversity (2 studies): One site comparison study in Mexico found that coffee agroforestry plantations using few or no chemicals had a higher diversity of insect-eating bat species than plantations with high chemical inputs, but the diversity of fruit and nectar-eating bat species did not differ. One paired sites study in Germany recorded more bat species over grassland with moderate or no fertiliser applications than grassland with high fertiliser applications. POPULATION RESPONSE (3 STUDIES) Abundance (2 studies): Two site comparison or paired sites studies (one replicated) in Portugal and Germany found that farms or grasslands with few or no chemical inputs had higher overall bat activity (relative abundance) than those using high chemical inputs. Condition (1 study): One replicated, site comparison study in Columbia found that great fruit-eating bats captured in ‘silvopastoral’ areas that used no chemicals, along with agroforestry, had higher body weights and body condition scores than those in conventional farming areas that used chemicals. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2013https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2013Wed, 05 Dec 2018 17:38:03 +0000Collected Evidence: Collected Evidence: Reduce pesticide or fertilizer use Three studies evaluated the effects on mammals of reducing pesticide, herbicide or fertilizer use. Two studies were in the UK, one was in Italy and one was in Argentina. COMMUNITY RESPONSE (1 STUDY) Richness/diversity (1 study): A replicated, site comparison study in Argentina found that farming without pesticides or fertilizers did not increase small mammal species richness in field margins. POPULATION RESPONSE (2 STUDIES) Abundance (2 studies): One of two site comparison studies, in the UK and Italy, found that reducing pesticide or fertilizer use, by farming organically, increased wood mouse abundance. The other study found that it did not increase European hare abundance. BEHAVIOUR (1 STUDY) Use (1 study): A replicated, site comparison study in Argentina found that farming without pesticides or fertilizers did not increase small mammal use of field margins. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2539https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2539Mon, 08 Jun 2020 17:16:27 +0100Collected Evidence: Collected Evidence: Reduce legal speed limit One study evaluated the effects on mammals of reducing the legal speed limit. This study was in Canada. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Survival (1 study): A controlled, before-and-after study in Canada found that speed limit reductions and enforcement did not reduce vehicle collisions with bighorn sheep or elk. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2596https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2596Thu, 11 Jun 2020 15:03:23 +0100Collected Evidence: Collected Evidence: Reduce pesticide, herbicide or fertilizer use We found no studies that evaluated the effects of reducing pesticide, herbicide or fertilizer use 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%2F2879https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2879Mon, 08 Feb 2021 11:44:13 +0000Collected Evidence: Collected Evidence: Reduce legal speed limit We found no studies that evaluated the effects of reducing the legal speed limit 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%2F3501https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3501Mon, 06 Dec 2021 17:42:48 +0000Collected Evidence: Collected Evidence: Reduce pesticide, herbicide or fertilizer use We found no studies that evaluated the effects on reptile populations of reducing pesticide, herbicide or fertilizer use. ‘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%2F3585https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3585Wed, 08 Dec 2021 15:33:48 +0000Collected Evidence: Collected Evidence: Reduce planting density to create warmer woodlands We found no studies that evaluated the effects on butterflies and moths of reducing planting density to create warmer woodlands. ‘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%2F3875https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3875Mon, 18 Jul 2022 16:04:49 +0100Collected Evidence: Collected Evidence: Reduce management intensity on permanent grasslands (several interventions at once) Twelve studies evaluated the effects on butterflies and moths of reducing management intensity on permanent grasslands. Seven studies were in Switzerland, three were in the UK, and one was in each of Greece and Germany. COMMUNITY RESPONSE (12 STUDIES) Community composition (2 studies): Two replicated studies (including one controlled study and one site comparison study) in Switzerland found that the composition of butterfly communities differed between low-input and intensively managed grasslands. One of these studies found that low-input grasslands tended to have more butterfly species whose caterpillars feed on a single host plant, have one generation/year and poor dispersal ability. Richness/diversity (11 studies): Six of 10 studies (including five controlled studies and five site comparison studies) in Switzerland, the UK, Greece and Germany found that less intensively managed grasslands had a higher species richness of butterflies and moths than conventionally managed grasslands, although two of these studies only found a difference in one of two years or regions. The other four studies found that less intensively managed grasslands had a similar species richness of butterflies and moths to conventionally managed grasslands. However, one of these studies also found that less intensively managed grassland had more specialist species of moths, and species of conservation concern, than conventionally managed grassland. One before-and-after study in the UK found that after grazing was reduced and chemical application stopped, the species richness of large moths increased. POPULATION RESPONSE (5 STUDIES) Abundance (5 studies): Three of four replicated studies (including two controlled studies and two site comparison studies) in Switzerland, the UK and Germany found that low-input or unfertilized, ungrazed grassland managed with a single cut had a higher abundance of butterflies, micro-moths and declining macro-moths than intensively managed grassland. Two of these studies also found that the abundance of caterpillars and of all macro-moths was similar between less intensively and more intensively managed grasslands. The other study found that less intensively managed grassland had a similar abundance of moths to more intensively managed grassland. One before-and-after study in the UK found that after grazing was reduced and chemical application stopped, the total abundance of large moths and the abundance of five out of 23 butterfly species increased, but the abundance of two butterfly species decreased. BEHAVIOUR (1 STUDY) Use (1 study): One replicated, site comparison study in Germany reported that 24 out of 58 moth species preferred less intensively managed grasslands, but 12 species preferred more intensively managed grasslands. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3958https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3958Sun, 14 Aug 2022 10:37:05 +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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