Collected Evidence: Collected Evidence: Leave uncropped, cultivated margins or plots, including lapwing and stone curlew plots Two studies and two reviews examined population-level effects of uncropped margins or plots. A before-and-after study from the UK and two reviews found an increase in Eurasian thick-knee Burhinus oedicnemus numbers following a scheme that promoted plots (amongst other interventions); a replicated study from the UK found no effect of plots on grey partridge density changes. Four studies (three replicated) and a review from the UK found that at least one species was associated with lapwing plots or used them for foraging or nesting. One replicated study from the UK found that 11 species were not associated with plots; another found that fewer birds used the plots than cropland in two out of three UK regions. Two of the three studies that examined productivity (one replicated) found that nesting success of birds was higher in fallow fields or lapwing plots than in crops. A replicated study from the UK found that grey partridge Perdix perdix productivity was not related to the amount of lapwing plots on a site and that the proportion of young partridges in the population was lower on sites with lots of cultivated fallow plots.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F213https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F213Tue, 17 Jul 2012 11:09:12 +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: Shield lights to reduce mortality from artificial lightsA replicated, controlled study in Hawaii found that fewer Newell’s shearwaters Puffinus newelli were found grounded when security lights were shielded, compared to nights when they were not.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F469https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F469Wed, 29 Aug 2012 16:27:35 +0100Collected Evidence: Collected Evidence: Grow non-crop plants that produce chemicals that attract natural enemiesNatural enemies: Four studies from China, Germany, India and Kenya tested the effects of growing plants that produce chemicals that attract natural enemies. Three (including one replicated, randomised, controlled trail) found higher numbers of natural enemies in plots with plants that produce attractive chemicals, and one found that the attractive plant also attracted natural enemies in lab studies. One found no effect on parasitism but the plant used was found not to be attractive to natural enemies in lab studies. Pests: All four studies found a decrease in either pest population or pest damage in plots with plants that produce chemicals that attract natural enemies. Yield: One replicated, randomised, controlled study found an increase in crop yield in plots with plants that produce attractive chemicals. Crops studied were lettuce, orange, safflower and sorghum.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F724https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F724Thu, 30 May 2013 13:11:05 +0100Collected Evidence: Collected Evidence: Leave part of the crop or pasture unharvested or uncutNatural enemies: We found eight studies from Australia, Germany, Hungary, New Zealand, Switzerland and the USA that tested leaving part of the crop or pasture unharvested or unmown. Three (including one replicated, controlled trial) found an increase in abundance of predatory insects or spiders in the crop field or pasture that was partly uncut, while four (including three replicated, controlled trials) found more predators in the unharvested or unmown area itself. Two studies (one replicated and controlled) found that the ratio of predators to pests was higher in partially cut plots and one replicated, controlled study found the same result in the uncut area. Two replicated, controlled studies found differing effects between species or groups of natural enemies. Predation and parasitism: One replicated, controlled study from Australia found an increase in predation and parasitism rates of pest eggs in unharvested strips. Pests: Two studies (including one replicated, controlled study) found a decrease in pest numbers in partially cut plots, one of them only for one species out of two. Two studies (one replicated, the other controlled) found an increase in pest numbers in partially cut plots, and two studies (including one replicated, controlled study) found more pests in uncut areas. Crops studied were alfalfa and meadow pasture.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F725https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F725Thu, 30 May 2013 13:16:14 +0100Collected Evidence: Collected Evidence: Install hop-overs as road/railway crossing structures for bats We found no studies that evaluated the effects of hop-overs as road/railway crossing structures for bats 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%2F980https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F980Fri, 20 Dec 2013 14:14:29 +0000Collected Evidence: Collected Evidence: Divert bats to safe crossing points over or under roads/railways with plantings or fencing One study evaluated the effects of diverting bats using an artificial hedgerow on bat populations. The study was in Switzerland. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (1 STUDY)      Use (1 study): One controlled, before-and-after study in Switzerland found that up to one fifth of lesser horseshoe bats within a colony flew along an artificial hedgerow to commute. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F981https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F981Fri, 20 Dec 2013 14:16:34 +0000Collected Evidence: Collected Evidence: Sow tree seeds after wildfire Three studies (including one replicated, randomized, controlled study) in the USA examined the effect of sowing herbaceous plant seeds in burnt forest areas. One found it decreased the number and cover of native species and one found it decreased the density of tree seedlings. All three found no effect of seeding on total plant cover or species richness.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1236https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1236Fri, 03 Jun 2016 08:34:24 +0100Collected Evidence: Collected Evidence: Remove burned trees One replicated, controlled study in Israel1 found that removing burned trees increased total plant species richness. One replicated, controlled study in Spain2 found that removal increased the cover and species richness of some plant species.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1237https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1237Fri, 03 Jun 2016 08:52:10 +0100Collected Evidence: Collected Evidence: Manually control or remove secondary mid-storey and ground-level vegetation We found no evidence for the effects of manually controlling or removing secondary mid-storey and ground-level vegetation 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%2F1492https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1492Tue, 17 Oct 2017 19:41:16 +0100Collected Evidence: Collected Evidence: Avoid slashing climbers/lianas, trees housing them, hemi-epiphytic figs, and ground vegetation We found no evidence for the effects of avoiding slashing climbers/lianas, trees housing them, hemi-epiphytic figs, and ground vegetation 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%2F1493https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1493Tue, 17 Oct 2017 19:42:38 +0100Collected Evidence: Collected Evidence: Provide new technologies to reduce pressure on wild biological resources We found no studies that evaluated the effects, on peatland vegetation, of providing new technologies (e.g. fuel-efficient stoves) to reduce pressure on wild biological resources. ‘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%2F1748https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1748Mon, 27 Nov 2017 21:29:05 +0000Collected Evidence: Collected Evidence: Restrict vehicle use on peatlands We found no studies that evaluated the effects, on peatland vegetation, of restricting vehicle use on peatlands. ‘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%2F1749https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1749Mon, 27 Nov 2017 21:31:21 +0000Collected Evidence: Collected Evidence: Use collar-mounted devices on cats to reduce predation of bats We found no studies that evaluated the effects of using collar-mounted devices on cats to reduce predation of bats 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%2F2004https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2004Wed, 05 Dec 2018 15:30:20 +0000Collected Evidence: Collected Evidence: Carry out surveillance of bats to prevent the spread of disease/viruses to humans to reduce human-wildlife conflict We found no studies that evaluated the effects of carrying out surveillance of bats to prevent the spread of disease/viruses to humans to reduce human-wildlife conflict. ‘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%2F2005https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2005Wed, 05 Dec 2018 15:31:18 +0000Collected Evidence: Collected Evidence: Locate artificial reefs near aquaculture systems to benefit from nutrient run-offs Two studies examined the effects of locating artificial reefs near aquaculture systems to benefit from nutrient run-offs on subtidal benthic invertebrate populations. One study was in the Gulf of Aqaba (Israel and Jordan), and one in the Mediterranean Sea (Spain).   COMMUNITY RESPONSE (1 STUDY) Overall community composition (1 study): One controlled study in the Mediterranean Sea found that an artificial reef located under aquaculture cages had similar invertebrate community composition to artificial reefs located at sites without aquaculture cages. POPULATION RESPONSE (1 STUDY) Overall abundance (1 study): One controlled study in the Gulf of Aqaba found that an artificial reef located at an aquaculture site had similar invertebrate biomass growing on it compared to an artificial reef located at a site without aquaculture cages. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2260https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2260Wed, 23 Oct 2019 10:51:01 +0100Collected Evidence: Collected Evidence: Place anthropogenic installations (e.g: windfarms) in an area such that they create artificial habitat and reduce the level of fishing activity We found no studies that evaluated the effects of placing anthropogenic installations in an area such that they reduce the level of fishing activity 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%2F2261https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2261Wed, 23 Oct 2019 10:51:55 +0100Collected Evidence: Collected Evidence: Translocate mammals away from sites of proposed energy developments Two studies evaluated the effects of translocating mammals away from sites of proposed energy developments. One study was in Brazil and one was in Australia. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (2 STUDIES) Behaviour change (2 studies): A study in Brazil found that lesser anteaters translocated away from a hydroelectric development site remained close to release sites while a study in Australia found that at least one out of eight chuditchs translocated from a site to be mined returned to its site of capture. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2517https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2517Mon, 08 Jun 2020 07:49:07 +0100Collected Evidence: Collected Evidence: Issue high fines and penalties for non-compliance with fisheries regulations We found no studies that evaluated the effects of issuing high fines and penalties for non-compliance with fisheries regulations 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%2F2772https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2772Wed, 03 Feb 2021 11:19:38 +0000Collected Evidence: Collected Evidence: License fish buyers We found no studies that evaluated the effects of licensing fish buyers 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%2F2773https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2773Wed, 03 Feb 2021 11:25:34 +0000Collected Evidence: Collected Evidence: Raise water level to restore degraded freshwater swampsWe found no studies that evaluated the effects, on vegetation, of raising the water level to restore degraded freshwater swamps.   ‘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%2F3028https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3028Wed, 31 Mar 2021 14:47:37 +0100Collected Evidence: Collected Evidence: Raise water level to restore degraded brackish/saline swampsWe found no studies that evaluated the effects, on vegetation, of raising the water level to restore degraded brackish/saline swamps.   ‘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%2F3029https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3029Wed, 31 Mar 2021 14:47:55 +0100Collected Evidence: Collected Evidence: Actively manage water level before/after planting trees/shrubs: brackish/saline wetlandsWe found no studies that evaluated the effects, on vegetation, of actively managing water levels in brackish/saline wetlands planted with trees/shrubs.   ‘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%2F3284https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3284Sat, 10 Apr 2021 17:16:15 +0100Collected Evidence: Collected Evidence: Enforce regulations to prevent trafficking and trade of reptiles We found no studies that evaluated the effects on reptile populations of enforcing regulations to prevent trafficking and trade of reptiles. ‘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%2F3540https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3540Tue, 07 Dec 2021 16:50:25 +0000Collected Evidence: Collected Evidence: Relocate nests/eggs for artificial incubation: Tortoises, terrapins, side-necked & softshell turtles Seventeen studies evaluated the effects of relocating nests/eggs for artificial incubation on tortoise, terrapin, side-necked & softshell turtle Ten studies were in the USA, two were in each of the Galápagos and China and one was in each of Brazil, Venezuela and Thailand. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (17 STUDIES) Reproductive success (16 studies): Two of three replicated controlled studies (including one randomized study) in Brazil, Venezuela and the USA found that Hilaire’s side-necked turtle and bog turtle nests relocated for artificial incubation had higher hatching success, or likely had higher success, than natural nests.The other study found that yellow-headed sideneck turtle nests relocated for artificial incubation had lower hatching success than natural nests and nests moved to an on-beach hatchery. One replicated study in the Galápagos reported that hatching success of five subspecies of giant tortoise nests relocated for artificial incubation was 35–100%, compared to 76–85% for natural nests of two sub species. Six of eight studies (including four replicated studies) in the USA and China reported that hatching success for artificially incubated eggs, including eggs recovered from road-killed turtles, was 60–97%, or that 314 hatchlings emerged, and 14 eggs did not hatch. One study also found that eggs collected from the wild had similar hatching success compared to oxytocin-induced eggs. The other two studies reported that hatching success of eggs or clutches was 39–54%. One replicated study in the Galápagos reported that hatching success of giant tortoise nests relocated for artificial incubation may have been higher for nests relocated longer after laying. One replicated study in the USA found that high levels of CO2 during artificial incubation of pond slider and Mississippi map turtle eggs resulted in lower hatching success compared to low CO2. One replicated, randomized study in China found that hatching success of artificially incubated Chinese three-keeled pond turtle eggs was similar across all temperatures tested. One randomized study in the USA found that hatching success of artificially incubated snapping turtle eggs was highest at intermediate levels of soil moisture. Survival (3 studies): Two studies (including one replicated study) in the USA reported that after relocating smooth softshell turtle and gopher tortoise nests for artificial incubation, two of 314 and three of 36 hatchlings died soon after emergence. One randomized study in the USA found that survival of artificially incubated snapping turtle hatchlings was lower at high soil moisture levels compared to intermediate moisture levels. Condition (4 studies): One replicated, randomized, controlled study in Brazil found that Hilaire’s side-necked turtle nests relocated for artificial incubation produced heavier hatchlings that were larger in four of five measures compared to hatchlings from natural nests. Two replicated studies (including one randomized study) in China found that modifying incubation temperatures of Chinese three-keeled pond turtle or Asian yellow pond turtle eggs had mixed effects on hatchling size and mobility or different effects on growth depending on the population eggs were sourced from. One replicated study in Thailand found that artificially incubating snail-eating turtle eggs at higher temperatures resulted in more embryos with physical deformities. BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Offspring sex ratio (1 study): One replicated study in the USA found that high levels of CO2 during artificial incubation of pond slider and Mississippi map turtle eggs resulted in a lower proportion of male hatchlings compared to low CO2 Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3796https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3796Wed, 15 Dec 2021 17:42:36 +0000
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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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