Collected 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: Modify culverts to make them more accessible to mammals One study evaluated the effects of modifying culverts to make them more accessible to mammals. This study was in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (1 STUDY) Use (1 study): A replicated, site comparison study in the USA found that modified culverts (with a dry walkway, open-air central section and enlarged entrances) were used more by bobcats to make crossings than were unmodified culverts. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2522https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2522Mon, 08 Jun 2020 10:38:29 +0100Collected Evidence: Collected Evidence: Install ledges in culverts under roads/railways Three studies evaluated the effects on mammals of installing ledges in culverts under roads or railways. Two studies were in the USA and one was in Portugal. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (3 STUDIES) Use (3 studies): A replicated, controlled study in Portugal found that under-road culverts with ledges were used more than culverts without ledges by two of five mammal species. A before-and-after study in the USA found that installing ledges within under-road culverts did not increase the number or diversity of small mammal species crossing through them, and only one of six species used ledges. A study in the USA found that ledges in under-road culverts were used by nine of 12 small mammal species and ledges with access ramps were used more often than those without. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2523https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2523Mon, 08 Jun 2020 10:50:11 +0100Collected Evidence: Collected Evidence: Dig trenches around culverts under roads/railways One study evaluated the effects on mammals of digging trenches around culverts under roads and/or railways. This study was in South Africa. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Survival (1 study): A replicated, randomized, controlled, before-and-after study in South Africa found that digging trenches alongside culverts did not reduce mammal mortality on roads. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2524https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2524Mon, 08 Jun 2020 11:41:56 +0100Collected Evidence: Collected Evidence: Install fences around existing culverts or underpasses under roads/railways Four studies evaluated the effects on mammals of installing fences around existing culverts under roads/railways. Two studies were in the USA one was in Portugal and one was in South Africa. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (3 STUDIES) Survival (3 studies): Two out of three before-and-after studies (including a controlled and a site comparison study), in the USA, Portugal and South Africa, found that installing or enhancing roadside fencing alongside existing culverts reduced mammal road mortality whilst one study found that such fences did not alter mammal road mortality. BEHAVIOUR (1 STUDY) Use (1 study): A replicated, randomized, controlled, before-and-after study in the USA found that fences installed to funnel animals to existing culverts did not increase culvert use by bobcats. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2525https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2525Mon, 08 Jun 2020 11:56:51 +0100Collected Evidence: Collected Evidence: Install barrier fencing along railways One study evaluated the effects on mammals of installing barrier fencing along railways. This study was in Norway. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Survival (1 study): A before-and-after study in Norway found that fencing eliminated moose collisions with trains, except at the fence end. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2590https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2590Thu, 11 Jun 2020 09:13:01 +0100Collected Evidence: Collected Evidence: Install acoustic wildlife warnings along roads Two studies evaluated the effects on mammals of installing acoustic wildlife warnings along roads. One study was in Demark and one was in Australia. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (2 STUDIES) Behaviour change (2 studies): A before-and-after study in Denmark found that sound from acoustic road markings did not alter fallow deer behaviour. A controlled study in Australia found that Roo-Guard® sound emitters did not deter tammar wallabies from food and so were not considered suitable for keeping them off roads. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2592https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2592Thu, 11 Jun 2020 13:09:39 +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: 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: 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: Modify vegetation along roads to reduce collisions with mammals by enhancing visibility for drivers We found no studies that evaluated the effects of modifying vegetation along roads to reduce collisions with mammals by enhancing visibility for drivers. ‘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%2F2599https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2599Thu, 11 Jun 2020 15:16:46 +0100Collected Evidence: Collected Evidence: Modify the roadside environment to reduce collisions by reducing attractiveness of road verges to mammals One study evaluated the effects of modifying the roadside environment to reduce collisions by reducing attractiveness of road verges to mammals. This study was in Canada. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (1 STUDY) (1 study): A replicated, before-and-after, site comparison study in Canada found that draining roadside salt pools and filling them with rocks reduced the number and duration of moose visits. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2600https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2600Thu, 11 Jun 2020 15:19:07 +0100Collected Evidence: Collected Evidence: Remove roadkill regularly to reduce kill rate of predators/scavengers We found no studies that evaluated the effects of removing roadkill regularly to reduce the kill rate of predators/scavengers. ‘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%2F2601https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2601Thu, 11 Jun 2020 15:32:32 +0100Collected Evidence: Collected Evidence: Modify vegetation along railways to reduce collisions by reducing attractiveness to mammals Two studies evaluated the effects of modifying vegetation along railways to reduce collisions by reducing attractiveness to wildlife. Both studies were in Norway. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Survival (2 studies): Two site comparison studies in Norway found that clearing vegetation from alongside railways reduced moose-train collisions. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2603https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2603Thu, 11 Jun 2020 15:34:27 +0100Collected Evidence: Collected Evidence: Retain/maintain road verges as small mammal habitat We found no studies that evaluated the effects of retaining or maintaining road verges as small mammal habitat. ‘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%2F2604https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2604Thu, 11 Jun 2020 15:49:04 +0100Collected Evidence: Collected Evidence: Fit vehicles with ultrasonic warning devices Three studies evaluated the effects on mammals of fitting vehicles with ultrasonic warning devices. Two studies were in the USA and one was in Australia. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Survival (1 study): A replicated, controlled study in Australia found that Shu Roo warning whistles did not reduce animal-vehicle collisions for eastern grey kangaroos or red kangaroos BEHAVIOUR (3 STUDIES) Behaviour change (3 studies): Three controlled studies (two replicated), in the USA and Australia, found that ultrasonic warning devices did not deter mule deer, eastern grey kangaroos, red kangaroos or white-tailed deer from roads. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2606https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2606Thu, 11 Jun 2020 15:50:34 +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: Use road lighting to reduce vehicle collisions with mammals Two studies evaluated the effects on mammals of using road lighting to reduce vehicle collisions with mammals. Both studies were in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Survival (2 studies): One of two studies (one controlled and one before-and-after), in the USA, found that road lighting reduced vehicle collisions with moose. The other study found that road lighting did not reduce vehicle collisions with mule deer. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2614https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2614Fri, 12 Jun 2020 08:16:01 +0100Collected Evidence: Collected Evidence: Use chemical repellents along roads or railways Five studies evaluated the effects on mammals of using chemical repellents along roads or railways. Two studies were in Canada and one each was in Germany, Norway and Denmark. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Survival (2 studies): Two studies (one before-and-after, one site comparison), in Germany and Norway, found that chemical-based repellents did not reduce collisions between ungulates and road vehicles or trains. BEHAVIOUR (4 STUDIES) Behaviour change (4 studies): Two of four studies (including three replicated, controlled studies), in Germany, Canada, and Denmark, found that chemical repellents, trialled for potential to deter animals from roads, did not deter ungulates. The other two studies found mixed results with repellents temporarily deterring some ungulate species in one study and one of three deterrents deterring caribou in the other. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2615https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2615Fri, 12 Jun 2020 08:24:14 +0100Collected Evidence: Collected Evidence: Use alternative de-icers on roads We found no studies that evaluated the effects on mammals of using alternative de-icers on roads. ‘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%2F2616https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2616Fri, 12 Jun 2020 09:06:31 +0100Collected Evidence: Collected Evidence: Provide food/salt lick to divert mammals from roads or railways Three studies evaluated the effects of providing food or salt licks to divert mammals from roads. One study was in the USA, one was in Norway and one was a review of studies from across North America and Europe. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Survival (2 studies): A replicated, controlled study in the USA found that intercept feeding reduced mule deer road deaths along two of three highways in one of two years. A replicated, site comparison study in Norway found that intercept feeding reduced moose collisions with trains. BEHAVIOUR (1 STUDY) Behaviour change (1 study): A review of feeding wild ungulates in North America, and Europe found that feeding diverted ungulates away from roads in one of three studies. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2617https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2617Fri, 12 Jun 2020 09:14:13 +0100Collected Evidence: Collected Evidence: Use reflective collars or paint on mammals to reduce collisions with road vehicles We found no studies that evaluated the effects of using reflective collars or paint on mammals to reduce collisions with road vehicles. ‘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%2F2619https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2619Fri, 12 Jun 2020 09:31:06 +0100Collected Evidence: Collected Evidence: Use wildlife decoy to reduce vehicle collisions with mammals We found no studies that evaluated the effects of using wildlife decoys to reduce vehicle collisions with mammals. ‘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%2F2620https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2620Fri, 12 Jun 2020 09:32:37 +0100Collected Evidence: Collected Evidence: Close roads in defined seasons One study evaluated the effects on mammals of closing roads in defined seasons. This study was in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (1 STUDY) Use (1 study): A site comparison study in the USA found that closing roads to traffic during the hunting season increased use of those areas by mule deer. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2626https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2626Fri, 12 Jun 2020 11:07:53 +0100
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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