Collected Evidence: Collected Evidence: Use in-water devices to reduce fish loss from ponds A before-and-after study from the USA found a 95% reduction in the number of double-crested cormorant Phalacrocorax auritus at two ponds in a fish farm following the installation of underwater ropes. A replicated study at a fish farm in Australia found that hanging gill nets in ponds did not decrease the number of cormorants swimming in ponds.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F254https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F254Wed, 18 Jul 2012 12:54:38 +0100Collected Evidence: Collected Evidence: Use legislative regulation to protect wild populations Six out of seven before-and-after studies and two literature reviews/meta-analyses found evidence that legislation protects bird populations. Five studies in Europe, Indonesia and across the world found increased population levels of vultures, raptors, cranes and cockatoos following protective legislation (amongst other interventions). However, one found populations of raptors declined soon after. The literature review also found two cases of limited or no impact of legislation. Two before-and-after studies from Denmark and the USA and Canada and the meta-analysis found increased estimated survival of falcons, ducks and parrots with stricter protection, but not necessarily population-level responses. A meta-analysis found decreased harvest of parrots in areas with stricter protection regimes, but a before-and-after study found no evidence for reduced shearwater harvest with legislation.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F271https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F271Thu, 19 Jul 2012 16:57:57 +0100Collected Evidence: Collected Evidence: Use larger hooks to reduce seabird bycatch We captured no intervention-based evidence on the impact of large hooks on seabird bycatch. '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%2F286https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F286Tue, 24 Jul 2012 16:26:21 +0100Collected Evidence: Collected Evidence: Use lion dung to deter domestic cats We found no evidence for the effects of lion dung application on the use of gardens by cats or on cat predation. '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%2F413https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F413Thu, 16 Aug 2012 15:19:11 +0100Collected Evidence: Collected Evidence: Use lime to reduce acidification in lakesA before-and-after study from Sweden found no difference in osprey Pandion haliaetus productivity during a period of extensive liming of acidified lakes compared to two periods without liming.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F465https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F465Wed, 29 Aug 2012 16:12:27 +0100Collected Evidence: Collected Evidence: Use lights low in spectral red to reduce mortality from artificial lightsTwo studies from the North Sea and the Netherlands found that fewer birds were attracted to low-red lights (including green and blue lights), compared with the number expected, or the number attracted to white or red lights.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F471https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F471Wed, 29 Aug 2012 16:40:31 +0100Collected Evidence: Collected Evidence: Use legislative regulation to protect wild populations One review found that legislation to reduce trade in two frog species resulted in the recovery of the over-exploited populations. One study in South Africa found that the number of permits issued for scientific and educational use of amphibians increased from 1987 to 1990.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F785https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F785Thu, 22 Aug 2013 14:10:37 +0100Collected Evidence: Collected Evidence: Use irrigation systems for amphibian sitesOne study investigating the effect of applying water to an amphibian site is outlined in ‘Threat: Energy production and mining - Artificially mist habitat to keep it damp’.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F804https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F804Thu, 22 Aug 2013 15:01:15 +0100Collected Evidence: Collected Evidence: Use leave-tree harvesting instead of clearcutting Two studies (including one randomized, replicated, controlled, before-and-after study) in the USA found that compared to clearcutting, leaving a low density of trees during harvest did not result in higher salamander abundance. Two studies (including one randomized, replicated, controlled, before-and-after study) in the USA found that compared to no harvesting, leaving a low density of trees during harvest decreased salamander abundance and changed species composition. One randomized, replicated, controlled, before-and-after study in the USA found that compared to unharvested plots, the proportion of female salamanders carrying eggs, eggs per female or proportion of juveniles were similar or lower in harvested plots that included leave-tree harvests, depending on species and time since harvest.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F846https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F846Fri, 30 Aug 2013 16:21:07 +0100Collected Evidence: Collected Evidence: Use low intensity lighting Three studies evaluated the effects of using low intensity lighting on bat populations. The three studies were in the UK. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Abundance (2 studies): One replicated, randomized, controlled study in the UK found that activity (relative abundance) of lesser horseshoe bats, but not myotis bats, was higher along hedges with medium or low intensity lighting than hedges with high intensity lighting. One replicated, randomized, controlled study in the UK found that activity of myotis bats, but not common pipistrelles, was higher along treelined roads with street lights dimmed to an intensity of 25% than roads with streetlights dimmed to 50% or left undimmed. BEHAVIOUR (1 STUDY)         Behaviour change (1 study): One replicated, controlled study in the UK found that more soprano pipistrelles emerged from two roosts when the intensity of red lights was reduced by placing filters over them. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1018https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1018Fri, 20 Dec 2013 17:58:34 +0000Collected Evidence: Collected Evidence: Use loud-speakers to broadcast sounds of potential threats (e.g. barking dogs, explosions, gunshots) We found no evidence for the effects of using loud-speakers to broadcast sounds of potential threats to crop-raiding primates 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%2F1446https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1446Tue, 17 Oct 2017 11:24:12 +0100Collected Evidence: Collected Evidence: Use loud-speakers to broadcast primate alarm calls We found no evidence for the effects of using loud-speakers to broadcast primate alarm calls to crop-raiding primates 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%2F1447https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1447Tue, 17 Oct 2017 11:35:42 +0100Collected Evidence: Collected Evidence: Use low impact harvesting techniques (for wild biological resources) We found no studies that evaluated the effects, on peatland vegetation, of using low impact harvesting techniques (for 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%2F1745https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1745Mon, 27 Nov 2017 21:27:41 +0000Collected Evidence: Collected Evidence: Use low impact vehicles for harvesting (wild biological resources) We found no studies that evaluated the effects, on peatland vegetation, of using specialized low impact vehicles for harvesting (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%2F1746https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1746Mon, 27 Nov 2017 21:28:10 +0000Collected Evidence: Collected Evidence: Use livestock fences that are permeable to wildlife Two studies evaluated the effects on target mammals of using livestock fences that are permeable to wildlife. Both studies were in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (2 STUDIES) Use (2 studies): A study in the USA found that wild ungulates crossed a triangular cross-section fence with varying success rates. A replicated, controlled study in the USA found that fences with a lowered top wire were crossed more by elk than were conventional fences. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2409https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2409Fri, 29 May 2020 12:28:23 +0100Collected Evidence: Collected Evidence: Use loud noises to deter predation of livestock by mammals to reduce human-wildlife conflict Three studies evaluated the effects of using loud noises to deter predation of livestock by mammals to reduce human-wildlife conflict. Two studies were in the USA and one was in Mexico. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (3 STUDIES) Human-wildlife conflict (3 studies): Three replicated studies (including two controlled studies), in the USA and Mexico, found that loud noises at least temporarily deterred sheep predation or food consumption by coyotes and (combined with visual deterrents) deterred livestock predation by large predators. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2435https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2435Tue, 02 Jun 2020 09:12:23 +0100Collected Evidence: Collected Evidence: Use lights and sound to deter predation of livestock by mammals to reduce human-wildlife conflict Three studies evaluated the effects of using lights and sound to deter predation of livestock by mammals to reduce human-wildlife conflict. All three studies were in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (3 STUDIES) Human-wildlife conflict (3 studies): Three replicated studies (including one controlled study), in the USA, found that devices emitting sounds and lights deterred predators from predating sheep or consuming bait. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2449https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2449Tue, 02 Jun 2020 10:49:54 +0100Collected Evidence: Collected Evidence: Use lights and sound to deter crop damage by mammals to reduce human-wildlife conflict Two studies evaluated the effects of using both lights and sound to deter crop damage by mammals to reduce human-wildlife conflict. Both studies were in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (2 STUDIES) Human-wildlife conflict (2 studies): Two replicated paired sites, controlled studies (one also randomized), in the USA, found that frightening devices, emitting lights and sound, did not reduce crop intrusions by white-tailed deer or food consumption by elk and mule deer. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2456https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2456Tue, 02 Jun 2020 11:14:41 +0100Collected Evidence: Collected Evidence: Use loud noises to deter crop damage (e.g. banger sticks, drums, tins, iron sheets) by mammals to reduce human-wildlife conflict Ten studies evaluated the effects of using loud noises to deter crop damage by mammals to reduce human-wildlife conflict. Three studies were in the USA, two were in Zimbabwe and Kenya and one each was in the UK, Namibia, and India. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (10 STUDIES) Human-wildlife conflict (10 studies): Five of six studies (including two controlled, one replicated and two before-and-after studies), in the USA, Namibia, Kenya and India, found that loud noises activated when an animal was in the vicinity reduced or partially reduced crop damage or crop visits by white-tailed deer, black-tailed deer (when combined with using electric shock collars) and elephants. The other study found that using loud noises (along with chili fences and chili smoke) did not reduce crop-raiding by African elephants. Three studies (including two controlled studies), in the UK and the USA, found that regularly sounding loud noises did not repel European rabbits or white-tailed deer. Two replicated studies, in Zimbabwe, found that, from among a range of deterrents, African elephants were repelled faster from crop fields when scared by firecrackers or by a combination of deterrents that included drums. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2460https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2460Tue, 02 Jun 2020 11:34:12 +0100Collected Evidence: Collected Evidence: Use light/lasers to deter crop damage by mammals to reduce human-wildlife conflict Two studies evaluated the effects of using light or lasers to deter crop damage by mammals to reduce human-wildlife conflict. Both studies were in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (2 STUDIES) Human-wildlife conflict (2 studies): A replicated, randomized, controlled study in the USA found that red lasers did not disperse white-tailed deer from fields at night whilst a study in India found that spotlights directed at the eyes of Asian elephants did reduce the probability of crop damage. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2496https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2496Thu, 04 Jun 2020 15:25:19 +0100Collected Evidence: Collected Evidence: Use larger hooks Two studies evaluated the effects of using larger hooks on reptile populations. One study was in the USA and one was in the Eastern Pacific Ocean. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (1 STUDY) Use (1 study): One study in the USA of captive loggerhead turtles found that turtles were less likely to attempt to swallow larger circle hooks than smaller ones. OTHER (1 STUDY) Unwanted catch (1 study): One replicated study in the Eastern Pacific Ocean found that olive ridley turtles were less likely to be caught by swallowing larger hooks than smaller ones. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3578https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3578Wed, 08 Dec 2021 15:21:29 +0000Collected Evidence: Collected Evidence: Use low intensity lighting Four studies evaluated the effects of using low intensity lighting on reptile populations. Three studies were in the USA1-3 and one was in Malaysia4. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (4 STUDIES) Behaviour change (4 studies): One replicated, controlled study in the USA1 found that reducing the intensity of light sources did not improve loggerhead turtle hatchling seaward orientation. One replicated, site comparison study in Malaysia4 found that green turtle hatchlings in low and moderate ambient artificial light took more direct crawl routes to the sea than hatchlings released in high ambient artificial light. One replicated, controlled study in the USA3 found that in laboratory trials, loggerhead and green turtle hatchlings showed reduced preference for lower intensity light sources. One replicated, site comparison study in the USA2 found mixed effects of embedding streetlights in the road on seaward orientation of loggerhead turtle hatchlings compared to overhead lighting depending on shading by shrubs and weather and lunar phase. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3623https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3623Thu, 09 Dec 2021 13:34:46 +0000Collected Evidence: Collected Evidence: Use irrigation systems Two studies evaluated the effects of using irrigation systems on reptile populations. Both studies were in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Reproductive success (1 study): One replicated, controlled study in the USA found that hatching success of Agassiz’s desert tortoises was similar in irrigated and non-irrigated enclosures. Survival (1 study): One replicated, controlled study in the USA found that survival of juvenile Agassiz’s desert tortoises was similar in irrigated and non-irrigated enclosures. Condition (2 studies): Two replicated, controlled studies (including one paired study) in the USA found that irrigating nests had mixed effects on growth of Agassiz’s desert tortoises and loggerhead turtles. One of the studies also found that loggerhead turtle hatchlings from nests that were irrigated were larger than those from non-irrigated nests. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3649https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3649Thu, 09 Dec 2021 15:53:32 +0000Collected Evidence: Collected Evidence: Use infrastructure to reduce vehicle collision risk along roads One study evaluated the effects on butterflies and moths of using infrastructure to reduce vehicle collision risk along roads. This study was in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (1 STUDY) Behaviour change (1 study): One controlled study in the USA reported that “altitude guide” netting, and poles topped with bright colours or flowers (attractive features), did not alter the behaviour of Oregon silverspot around roads. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3853https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3853Tue, 05 Jul 2022 11:41:12 +0100Collected Evidence: Collected Evidence: Use leave-tree harvesting instead of clearcutting We found no studies that evaluated the effects on butterflies and moths of using leave-tree harvesting instead of clearcutting. ‘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%2F3870https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3870Mon, 18 Jul 2022 15:46:58 +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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