Collected Evidence: Collected Evidence: Reduce the intensity of farmland meadow managementFour replicated trials in Europe have compared farmland meadows managed extensively with conventionally farmed meadows or silage fields. Two found enhanced numbers and diversity of wild bees on meadows with a delayed first cut and little agrochemical use. Two found no difference in bee diversity or abundance between conventional meadows and meadows with reduced fertilizer use or cutting intensity.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F22https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F22Thu, 20 May 2010 19:27:37 +0100Collected Evidence: Collected Evidence: Reduce seabird bycatch by releasing offal overboard when setting longlinesTwo replicated and controlled studies in the South Atlantic and sub-Antarctic Indian Ocean found significant reductions in the number of albatross and petrels attacking baits and being caught when offal was released overboard during line setting.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F299https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F299Tue, 24 Jul 2012 17:39:55 +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 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 the intensity of lighthouse beams We found no evidence for the effects of reducing the intensity of lighthouse beams on bird mortality. '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%2F468https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F468Wed, 29 Aug 2012 16:25:43 +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 the intensity of livestock grazing in forests One replicated study in the UK found that reducing grazing intensity increased the number of tree saplings. One replicated, randomized, controlled study in Greece found that reducing grazing intensity increased understory biomass.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1207https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1207Thu, 19 May 2016 14:24:40 +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 the size of forestry teams to include employees only (not family members) We found no evidence for the effects of reducing the size of forestry teams to include employees only and not family members 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%2F1499https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1499Tue, 17 Oct 2017 19:53:29 +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 the frequency of prescribed burning We found no studies that evaluated the effects of reducing the frequency of prescribed burning 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%2F1614https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1614Sun, 22 Oct 2017 10:29:34 +0100Collected 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 ships/boats/vessels speed limits We found no studies that evaluated the effects of reducing ships/boats/vessels speed limits 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%2F2095https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2095Mon, 21 Oct 2019 15:24:31 +0100Collected Evidence: Collected Evidence: Reduce the number or modify the arrangement of tickler chains/chain mats on trawl nets Three studies examined the effects of reducing the number or modifying the arrangement of tickler chains/chain mats on subtidal benthic invertebrates. All studies were in the North Sea (Germany and Netherlands).   COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (3 STUDIES) Overall abundance (1 study): One replicated, paired, controlled study in the North Sea found that using a beam trawl with a chain mat caused lower mortality of benthic invertebrates in the trawl tracks compared to using a beam trawl with tickler chains. Unwanted catch abundance (2 studies): One of two replicated, paired, controlled studies in the North Sea found that all three modified parallel tickler chain arrangements reduced the combined amount of non-commercial unwanted invertebrate and fish catch compared to unmodified trawl nets, but the other found that none of three modified parabolic tickler chain arrangements reduced it. OTHER (2 STUDIES) Commercial catch abundance (2 studies): One of two replicated, paired, controlled studies in the North Sea found that three modified parabolic tickler chain arrangements caught similar amounts of commercial species to unmodified nets, but the other found that three modified parallel tickler chain arrangements caught lower amounts. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2140https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2140Tue, 22 Oct 2019 11:02:53 +0100Collected Evidence: Collected Evidence: Reduce the amount of pesticides used in aquaculture systems We found no studies that evaluated the effects of reducing the amount of pesticides used in aquaculture systems 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%2F2193https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2193Tue, 22 Oct 2019 13:05:17 +0100Collected Evidence: Collected Evidence: Reduce the amount of antibiotics used in aquaculture systems We found no studies that evaluated the effects of reducing the amount of antibiotics used in aquaculture systems 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%2F2194https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2194Tue, 22 Oct 2019 13:06:02 +0100Collected Evidence: Collected Evidence: Reduce the hauling speed of a trawl net We found no studies that evaluated the effects of reducing the hauling speed of a trawl net on marine fish 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%2F2688https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2688Wed, 02 Dec 2020 10:47:28 +0000Collected Evidence: Collected Evidence: Reduce the duration of exposure to air of captured fish before release Three studies examined the effect of reducing the duration of exposure of fish to air on marine fish populations. One study was in each of the Bay of Biscay (Spain), Gulf of Alaska (Canada) and Coral Sea (Australia).  COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Survival (1 study): One replicated study in the Bay of Biscay found that reducing air exposure before release did not increase the survival of small-spotted catshark caught during commercial trawling. Condition (1 study): One replicated study in the Gulf of Alaska found that shorter durations of air exposure before release improved the physical condition and reduced the amount of injury to discarded chum salmon caught in purse seine nets.  BEHAVIOUR (1 STUDY) Behaviour change (1 study): One study in the Coral Sea found that minimal exposure to air and handling resulted in improved overall behaviour after release (activity and ability to return to reef) of reef fish, compared to fish exposed to air and handling for longer duration. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2690https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2690Wed, 02 Dec 2020 14:47:25 +0000Collected Evidence: Collected Evidence: Reduce shipping along inland waterways We found no studies that evaluated the effects of reducing shipping along inland waterways on 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%2F2763https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2763Tue, 02 Feb 2021 17:07:40 +0000Collected Evidence: Collected Evidence: Reduce the amount of pesticides used in aquaculture systems We found no studies that evaluated the effects of reducing the amount of pesticides used in 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%2F2877https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2877Mon, 08 Feb 2021 11:42:45 +0000Collected Evidence: Collected Evidence: Reduce the amount of antibiotics used in aquaculture systems We found no studies that evaluated the effects of reducing the amount of antibiotics used in 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%2F2878https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2878Mon, 08 Feb 2021 11:43:28 +0000Collected 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 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 +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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