Collected Evidence: Collected Evidence: Insulate power pylons to prevent electrocutionA single before-and-after study in the USA found the insulating power pylons significantly reduced the number of Harris’s hawks Parabuteo unicinctus electrocuted.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F268https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F268Thu, 19 Jul 2012 16:10:27 +0100Collected Evidence: Collected Evidence: Integrated aquaculture systems One replicated, controlled study in the USA reported greater growth of scallops grown next to fish farms. A study in Canada found that blue mussels absorbed waste from a salmon farm. A replicated, controlled study in Scotland reported enhanced algal growth when placed adjacent to fish farms. One study in Spain found no evidence that oyster and mussels were feeding on fish farm waste.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F932https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F932Fri, 25 Oct 2013 13:57:09 +0100Collected Evidence: Collected Evidence: Install underpasses or culverts as road/railway crossing structures for bats Eight studies evaluated the effects of installing underpasses or culverts as road crossing structures for bats. Seven studies were in Europe and one in Australia. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (8 STUDIES)      Use (8 studies): Eight studies (including six replicated studies) in Germany, Ireland, the UK, Australia and France found that bats used underpasses and culverts below roads, and crossed over the roads above them, in varying proportions. One replicated, site comparison study in Australia found that bat species adapted to cluttered habitats used small culverts and underpasses more than bat species adapted to open or edge habitats. One replicated, site comparison study in France found that the use of underpasses by five bat species was influenced by underpass type and height, road width, and the amount of forest and hedgerows in the surrounding landscape. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F976https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F976Fri, 20 Dec 2013 14:08:31 +0000Collected Evidence: Collected Evidence: Install rope or pole (canopy) bridges One study in Brazil found that black lion tamarins and capuchins used a pole bridge to cross a road. One before-and-after study in Belize found that a black howler monkey population increased after the construction of pole bridges over man-made gaps. One before-and-after study in Madagascar found that all six monitored lemur species used bridges to cross roads and pipelines. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1457https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1457Tue, 17 Oct 2017 13:28:40 +0100Collected Evidence: Collected Evidence: Install speed bumps to reduce vehicle collisions with primates We found no evidence for the effects of installing speed bumps to reduce vehicle collisions with 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%2F1465https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1465Tue, 17 Oct 2017 14:11:01 +0100Collected Evidence: Collected Evidence: Integrate religion/local taboos into conservation education We found no evidence for the effects of integrating religion/local taboos into conservation education. '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%2F1574https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1574Fri, 20 Oct 2017 12:30:22 +0100Collected Evidence: Collected Evidence: Install sound-proofing insulation between bat roosts and areas occupied by humans within developments We found no studies that evaluated the effects of installing sound-proofing insulation between bat roosts and areas occupied by humans within developments 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%2F1929https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1929Fri, 30 Nov 2018 13:47:18 +0000Collected Evidence: Collected Evidence: Install sound barriers in proximity to bat roosts and habitats We found no studies that evaluated the effects of installing sound barriers in proximity to bat roosts and habitats 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%2F2023https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2023Wed, 05 Dec 2018 18:09:06 +0000Collected Evidence: Collected Evidence: Install stormwater traps or grids We found no studies that evaluated the effects of installing stormwater traps or grids 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%2F2203https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2203Tue, 22 Oct 2019 13:14:36 +0100Collected Evidence: Collected Evidence: Install underpasses beneath ski runs One study evaluated the effects on mammals of installing underpasses beneath ski runs. This study was in Australia. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (1 STUDY) Use (1 study): A replicated study in Australia found that boulder-filled crossings beneath ski slopes were used by seven small mammal species. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2355https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2355Tue, 26 May 2020 11:59:24 +0100Collected Evidence: Collected Evidence: Install tunnels/culverts/underpass under roads Twenty-five studies evaluated the effects on mammals of installing tunnels, culverts or underpass under roads. Eight studies were in the USA, four were in Australia, four were in Canada, two were in Spain, one each was in Germany, the Netherlands and South Korea and three were reviews with wide geographic coverage. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (3 STUDIES) Survival (3 studies): A study in South Korea found that road sections with higher underpass density did not have fewer wildlife-vehicle collisions. A review found that most studies recorded no evidence of predation of mammals using crossings under roads. A controlled, before-and-after, site comparison study in Australia found that overwinter survival of mountain pygmy-possums increased after an artificial rocky corridor, which included two underpasses, was installed. BEHAVIOUR (23 STUDIES) Use (23 studies): Seventeen of 20 studies (including seven replicated studies and two reviews), in the USA, Canada, Australia, Spain, the Netherlands, and across multiple continents, found that crossing structures beneath roads were used by mammals whilst two studies found mixed results depending on species and one study found that culverts were rarely used as crossings by mammals. One of the studies found that crossing structures were used by two of four species more than expected compared to their movements through adjacent habitats. A controlled, before-and-after, site comparison study in Australia found that an artificial rocky corridor, which included two underpasses, was used by mountain pygmy-possums. A replicated study in Germany found that use of tunnels by fallow deer was affected by tunnel colour and design. A study in the USA found that a range of mammals used culverts, including those with shelves fastened to the sides. Behaviour change (1 study): A controlled, before-and-after, site comparison study in Australia found that after an artificial rocky corridor, which included two underpasses, was installed, dispersal of mountain pygmy-possums increased. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2514https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2514Fri, 05 Jun 2020 10:17:32 +0100Collected Evidence: Collected Evidence: Install tunnels/culverts/underpass under railways Six studies evaluated the effects on mammals of installing tunnels, culverts or underpass under railways. Two studies were in Spain, one was in each of Australia, Canada and the Netherlands and one reviewed literature from a range of countries. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Survival (1 study): A review found that most studies recorded no evidence of predation in or around passages under railways or roads of mammals using those passages. BEHAVIOUR (5 STUDIES) Use (5 studies): Five studies, in Spain, Australia, Canada and the Netherlands, found that tunnels, culverts and underpasses beneath railways were used by a range of mammals including rodents, rabbits and hares, carnivores, marsupials, deer and bears. One of these studies found that existing culverts were used more than were specifically designed wildlife tunnels. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2519https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2519Mon, 08 Jun 2020 09:27:22 +0100Collected Evidence: Collected Evidence: Install pole crossings for gliders/flying squirrels Seven studies evaluated the effects on gliders/flying squirrels of installing pole crossings. Six studies were in Australia and one was in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Survival (1 study): A study in Australia found that arboreal marsupials using artificial road crossing structures did not suffer high predation rates when doing so. BEHAVIOUR (6 STUDIES) Use (6 studies): Six studies (five replicated), in Australia and the USA, found that poles were used for crossing roads by squirrel gliders, sugar gliders and Carolina northern flying squirrels. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2546https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2546Tue, 09 Jun 2020 09:20:33 +0100Collected Evidence: Collected Evidence: Install rope bridges between canopies Ten studies evaluated the effects on mammals of install rope bridges between canopies. Eight studies were in Australia, one was in Brazil and one in Peru. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Survival (1 study): A study in Australia found that arboreal marsupials using rope bridges did not suffer high predation rates when doing so. BEHAVIOUR (9 STUDIES) Use (9 studies): Nine studies (including three replicated studies and a site comparison), in Australia, Brazil and Peru found that rope bridges were used by a range of mammals. Seven of these studies found between three and 25 species using rope bridges, one found that that they were used by squirrel gliders and one that they were used by mountain brushtail possums and common ringtail possums but not by koalas and squirrel gliders. One of the studies found that crossing rates were higher over the canopy bridges than at ground level. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2556https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2556Tue, 09 Jun 2020 10:50:37 +0100Collected Evidence: Collected Evidence: Install wildlife warning reflectors along roads Fifteen studies evaluated the effects on mammals of installing wildlife warning reflectors along roads. Nine studies were in the USA, three were in Austalia, two were in Germany and one was in Denmark. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (10 STUDIES) Abundance (1 study): A before-and-after study in Australia found that when warning reflectors were installed (along with speed restrictions, reflective wildlife signs, rumble strips, wildlife escape ramps and an educational pamphlet) a small population of eastern quoll re-established in the area. Survival (10 studies): Five of eight controlled or before-and-after studies in the USA and Germany found that wildlife warning reflectors did not reduce collisions between vehicles and deer. Two studies found that vehicle-deer collisions were reduced by reflectors and one found that collisions were reduced in rural areas but increased in suburban areas. A before-and-after study in Australia found that when warning reflectors were installed (along with speed restrictions, reflective wildlife signs, rumble strips, wildlife escape ramps and an educational pamphlet) vehicle collisions with Tasmanian devils, but not eastern quolls, decreased. A review of two studies in Australia found mixed responses of mammal road deaths to wildlife warning reflectors. BEHAVIOUR (5 STUDIES) Behaviour change (5 studies): Three of four studies (including three controlled studies), in the USA, Denmark and Germany, found that wildlife warning reflectors did not cause deer to behave in ways that made collisions with vehicles less likely (such as by avoiding crossing roads). The other study found that deer initially responded to wildlife reflectors with alarm and flight but then became habituated. A replicated, controlled study in Australia found that one of four reflector model/colour combinations increased fleeing behaviour of bush wallabies when lights approached. The other combinations had no effect and none of the combinations affected red kangaroos. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2591https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2591Thu, 11 Jun 2020 09:30:25 +0100Collected Evidence: Collected Evidence: Install wildlife crosswalks One study evaluated the effects on mammals of installing wildlife crosswalks. This study was in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Survival (1 study): A replicated, before-and-after, site comparison study in the USA found that designated crossing points with barrier fencing did not significantly reduce road deaths of mule deer. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2593https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2593Thu, 11 Jun 2020 13:27:43 +0100Collected Evidence: Collected Evidence: Install wildlife exclusion grates/cattle grids Three studies evaluated the effects on mammals of installing wildlife exclusion grates or cattle grids. All three studies were in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (3 STUDIES) Behaviour change (3 studies): Two of three studies (including two replicated, before-and-after studies), in the USA, found that steel grates largely prevented crossings by deer whilst two found that they did not prevent crossings by deer and elk or black bears. In one of the studies, only one of three designs prevented crossings. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2594https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2594Thu, 11 Jun 2020 13:35:42 +0100Collected Evidence: Collected Evidence: Install traffic calming structures to reduce speeds One study evaluated the effects on mammals of installing traffic calming structures to reduce speeds. This study was in Australia. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): A before-and-after study in Australia found that following installation of barriers to create a single lane, rumble strips, reflective wildlife signs, reflective wildlife deterrents, wildlife escape ramps and production of an educational pamphlet, a small population of eastern quoll population re-established in the area. Survival (1 study): A before-and-after study in Australia found that following installation of barriers to create a single lane, rumble strips, reflective wildlife signs, reflective wildlife deterrents, wildlife escape ramps and production of an educational pamphlet, vehicle collisions with Tasmanian devils, but not eastern quolls decreased. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2598https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2598Thu, 11 Jun 2020 15:10:14 +0100Collected Evidence: Collected Evidence: Install signage to warn motorists about wildlife presence Six studies evaluated the effects on mammals of installing signage to warn motorists about wildlife presence. Four studies were in the USA one was in Australia and one was in Canada. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (6 STUDIES) Abundance (1 study): A before-and-after study in Australia found that when wildlife signs were installed along with speed restrictions, rumble strips, reflective wildlife deterrents, wildlife escape ramps and an educational pamphlet, a small population of eastern quoll re-established in the area. Survival (6 studies): Three of five studies (including four controlled and three before-and-after studies), in the USA and Canada, found that warning signs did not reduce collisions between vehicles and deer. The other two studies found that warning signs did reduce collisions between vehicles and deer. A before-and-after study in Australia found that wildlife signs along with speed restrictions, rumble strips, reflective wildlife deterrents, wildlife escape ramps and an educational pamphlet, reduced collisions between vehicles and Tasmanian devils but not eastern quolls. BEHAVIOUR (0 STUDIES) OTHER (2 STUDIES) Human behaviour change (2 studies): Two controlled studies (one also replicated, before-and-after), in the USA, found that signs warning of animals on the road reduced vehicles speeds. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2608https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2608Thu, 11 Jun 2020 16:22:25 +0100Collected Evidence: Collected Evidence: Install stormwater traps or grids We found no studies that evaluated the effects of installing stormwater traps or grids 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%2F2894https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2894Mon, 08 Feb 2021 11:58:26 +0000Collected Evidence: Collected Evidence: Integrate marshes or swamps into developed areasWe found no studies that evaluated the effects, on vegetation, of incorporating marshes or swamps into developed areas.   ‘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%2F2948https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2948Mon, 01 Mar 2021 16:15:08 +0000Collected Evidence: Collected Evidence: Install physical supports for planted trees/shrubs: freshwater wetlandsWe found no studies that evaluated the effects of installing physical supports for trees/shrubs planted in freshwater wetlands.   ‘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%2F3338https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3338Sun, 11 Apr 2021 16:38:46 +0100Collected Evidence: Collected Evidence: Install tunnels/culverts/underpasses under roads/railways Fifteen studies evaluated the effects of installing tunnels/culverts/underpasses under roads/railways on reptile populations. Four of the studies were in the USA, four were in Australia, three were in Spain, two were in Canada and one was in each of Australia, Europe and North America and South Africa. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (3 STUDIES) Survival (3 studies): Two site comparison studies (including one before-and-after study) in Australia and South Africa found a similar number of reptile road mortalities with or without culverts or wildlife underpasses. One replicated study in Spain found that the number of underpasses in an area did not affect the number of reptile road mortalities. BEHAVIOUR (12 STUDIES) Use (12 studies): Six studies (including four replicated studies and one replicated, before-and-after study) and one review in Spain, Australia, the USA and Australia, Europe and North America found that crossing structures, including tunnels, culverts, underpasses, pipes and trenches under roads and railways were used by reptiles, lizards, snakes and/or tortoises. One review in Australia, Europe and North America also found that wildlife underpasses were used by reptiles in only one of 13 studies. Three of four replicated studies (including one before-and-after study) in the USA and Canada found that desert tortoises, painted and snapping turtles and rattlesnakes and garter snakes showed a willingness to enter some, or all types of tunnel. The other study found that only 9% of painted turtles entered a culvert during a choice experiment. One site comparison study in Australia found that the area under an overpass was used by five reptile species. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3508https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3508Tue, 07 Dec 2021 11:55:41 +0000Collected Evidence: Collected Evidence: Install stormwater traps to prevent garbage from reaching rivers, coastal and marine environments We found no studies that evaluated the effects on reptile populations of installing stormwater traps to prevent garbage from reaching rivers, coastal and marine environments. ‘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%2F3589https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3589Wed, 08 Dec 2021 15:59:03 +0000Collected Evidence: Collected Evidence: Install sound barriers in proximity to reptile habitats We found no studies that evaluated the effects on reptile populations of installing sound barriers in proximity to reptile habitats. ‘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%2F3640https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3640Thu, 09 Dec 2021 15:09:25 +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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