Collected Evidence: Collected Evidence: Keep cats indoors or in outside runs to reduce predation of wild mammals One study evaluated the effects on potential prey mammals of keeping cats indoors or in outside runs. This study was in the UK. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Survival (1 study): One replicated study in the UK found that keeping domestic cats indoors at night reduced the number of dead or injured mammals that were brought home. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2326https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2326Thu, 21 May 2020 09:53:43 +0100Collected Evidence: Collected Evidence: Keep dogs indoors or in outside enclosures to reduce threats to wild mammals We found no studies that evaluated the effects on mammals of keeping dogs indoors or in outside enclosures to reduce threats to wild 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%2F2334https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2334Thu, 21 May 2020 13:18:55 +0100Collected Evidence: Collected Evidence: Keep domestic cats and dogs well-fed to reduce predation of wild mammals We found no studies that evaluated the effects on mammals of keeping domestic cats and dogs well-fed to reduce predation of wild 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%2F2335https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2335Thu, 21 May 2020 13:21:00 +0100Collected Evidence: Collected Evidence: Issue enforcement notices to deter use of non bear-proof garbage dumpsters to reduce human-wildlife conflict One study evaluated the effects of issuing enforcement notices to deter use of non bear-proof garbage dumpsters to reduce human-wildlife conflict. This study was in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Human-wildlife conflict (1 study): A replicated, controlled, before-and-after study in the USA found that issuing enforcement notices requiring appropriate dumpster use did not reduce garbage accessibility to black bears. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2345https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2345Fri, 22 May 2020 13:17:38 +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: Maintain/restore/create habitat connectivity on farmland We found no studies that evaluated the effects on mammals of maintaining, restoring or creating habitat connectivity on farmland. ‘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%2F2381https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2381Wed, 27 May 2020 14:29:56 +0100Collected Evidence: Collected Evidence: Manage hedgerows to benefit wildlife on farmland We found no studies that evaluated the effects on mammals of managing hedgerows to benefit wildlife on farmland. ‘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%2F2382https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2382Wed, 27 May 2020 14:33:07 +0100Collected Evidence: Collected Evidence: Leave areas of uncut ryegrass in silage field We found no studies that evaluated the effects on mammals of leaving areas of uncut ryegrass in silage field. ‘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%2F2400https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2400Thu, 28 May 2020 10:59:29 +0100Collected Evidence: Collected Evidence: Leave cut vegetation in field to provide cover One study evaluated the effects on mammals of leaving cut vegetation in field to provide cover. This study was in the USA KEY COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): A controlled, before-and-after study in the USA found that increasing cover, by adding cut vegetation (hay), did not increase rodent abundance. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2401https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2401Thu, 28 May 2020 11:01:45 +0100Collected Evidence: Collected Evidence: Keep livestock in enclosures to reduce predation by mammals to reduce human-wildlife conflict One study evaluated the effects of keeping livestock in enclosures to reduce predation by mammals to reduce human-wildlife conflict. This study was in Portugal. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Human-wildlife conflict (1 study): A replicated study in Portugal found fewer wolf attacks on cattle on farms where cattle were confined for at least some of the time compared to those with free-ranging cattle. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2438https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2438Tue, 02 Jun 2020 09:42:50 +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: Leave headlands in fields unsprayed Two studies evaluated the effects on mammals of leaving headlands in fields unsprayed. One study was in the UK and one was in the Netherlands. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (2 STUDIES) Use (2 studies): Two replicated studies (one also controlled) in the UK and the Netherlands, found that crop edge headlands that were not sprayed with pesticides were used more by mice than were sprayed crop edges. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2540https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2540Mon, 08 Jun 2020 17:43:19 +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: Manage vegetation using grazing by wild herbivores Two studies evaluated the effects on mammals of managing vegetation using grazing by wild herbivores. One study was in the USA and one was in South Africa. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Abundance (2 studies): A site comparison study in the USA found that areas with higher numbers of wild herbivore grazers hosted more small mammals than did areas grazed by fewer wild herbivores. A study in South Africa found that grazing by Cape mountain zebras did not lead to a higher population of bontebok. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2548https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2548Tue, 09 Jun 2020 09:59:23 +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: Legally protect habitat for mammals Seven studies evaluated the effects of legally protecting habitat for mammals. One study each was in Zambia, the USA, Tanzania, Brazil, Nepal and India and one was a systematic review of sites with a wide geographic spread. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (7 STUDIES) Abundance (7 studies): A systematic review of protected areas across the globe found that 24 of 31 studies reported an increase in mammal populations in protected areas relative to unprotected areas. Three studies (including two site comparison studies), in Zambia, the USA and Nepal, found that populations of red lechwe, black bears and one-horned rhinoceros grew following site protection or were higher than in adjacent non-protected sites. One of three site comparison studies, in Tanzania, Brazil and India, found that populations of more mammal species increased inside protected areas than in adjacent unprotected areas. One study found that populations of only three of 11 species were higher on protected than on unprotected land whilst the third study found that 13 of 16 species were less abundant in a protected area than in a nearby unprotected area. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2559https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2559Tue, 09 Jun 2020 11:56:39 +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: Make introduction of non-native mammals for sporting purposes illegal We found no studies that evaluated the effects on native mammals of making introduction of non-native mammals for sporting purposes illegal. ‘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%2F2621https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2621Fri, 12 Jun 2020 10:47:21 +0100Collected Evidence: Collected Evidence: Leave standing deadwood/snags in forests One study evaluated the effects on mammals of leaving standing deadwood or snags in forests. This study was in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): A replicated, controlled study in the USA found that increasing the quantity of standing deadwood in forests increased the abundance of one of three shrew species, compared to removing deadwood. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2646https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2646Fri, 12 Jun 2020 17:32:19 +0100Collected Evidence: Collected Evidence: Leave coarse woody debris in forests Three studies evaluated the effects on mammals of leaving coarse woody debris in forests. One study was in Canada, one was in the USA and one was in Malaysia. COMMUNITY RESPONSE (1 STUDY) Richness/diversity (1 study): A replicated, site comparison study, in Malaysia found more small mammal species groups in felled forest areas with woody debris than without. POPULATION RESPONSE (3 STUDIES) Abundance (3 studies): One out of three replicated studies (two controlled, one site comparison, one before-and-after) in Canada, the USA and Malaysia found that retaining or adding coarse woody debris did not increase numbers or frequency of records of small mammals. The other study found that two of three shrew species were more numerous in areas with increased volumes of coarse woody debris than areas without coarse woody debris. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2647https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2647Fri, 12 Jun 2020 17:38:11 +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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