Collected Evidence: Collected Evidence: Install barrier fencing and underpasses along roads Fifty-five studies evaluated the effects on mammals of installing barrier fencing and underpasses along roads. Twenty-seven were in the USA, nine were in Canada, seven were in Australia, two each were in Spain, Portugal, the UK and Sweden, one each was in Denmark, Germany and Croatia and one was a review covering Australia, Europe and North America. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (15 STUDIES) Survival (15 studies): Eleven of 15 studies (including 12 before-and-after studies and two site comparisons), in the USA, Australia, Sweden and Canada, found that installing underpasses and associated roadside barrier fencing reduced collisions between vehicles and mammals. Three studies found that the roadkill rate was not reduced and one study found that vehicle-mammal collisions continued to occur after installation. BEHAVIOUR (52 STUDIES) Use (52 studies): Seventeen of 18 studies (including 10 before-and-after studies) in the USA, Canada and Sweden, which reported exclusively on ungulates, found that underpasses installed along with roadside barrier fencing were used by a range of ungulate species. These were mule deer, mountain goat, pronghorn, white-tailed deer, elk, moose and Florida Key deer. The other study found that underpasses were not used by moose whilst one of the studies that did report use by ungulates further reported that they were not used by white-tailed deer. Further observations from these studies included that elk preferred more open, shorter underpasses to those that were enclosed or longer, underpass use was not affected by traffic levels and that mule deer used underpasses less than they used overpasses. Thirty-four studies (including four before-and-after studies, seven replicated studies, three site comparisons and two reviews), in the USA, Canada, Australia, Spain, Portugal, the UK, Denmark, Germany, Croatia and across multiple continents, that either studied mammals other than ungulates or multiple species including ungulates, found that underpasses in areas with roadside fencing were used by mammals. Among these studies, one found that small culverts were used by mice and voles more than were larger underpasses, one found that bandicoots used underpasses less after they were lengthened and one found that culverts were used by grizzly bears less often than were overpasses. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2571https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2571Wed, 10 Jun 2020 08:35:55 +0100Collected Evidence: Collected Evidence: Restore or create wetlands Four studies evaluated the effects on mammals of restoring or creating wetlands. Three studies were in the USA and one was in the UK. COMMUNITY RESPONSE (2 STUDIES) Community composition (1 study): A site comparison study in the USA found that the composition of mammal species present differed between a created and a natural wetland. Richness/diversity (2 studies): Two site comparison studies (one replicated) in the USA, found that mammal species richness did not differ between created and natural wetlands. POPULATION RESPONSE (2 STUDIES) Abundance (1 study): A before-and-after study in the USA found that following marshland restoration, muskrat abundance increased. Survival (1 study): A replicated, controlled, before-and-after study in the UK, found that water voles persisted better in wetlands that were partially restored using mechanical or manual methods than they did in wetlands undergoing complete mechanical restoration. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2572https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2572Wed, 10 Jun 2020 09:45:41 +0100Collected Evidence: Collected Evidence: Sterilize predators One study evaluated the effects on potential prey mammals of sterilizing predators. This study was in the USA and Canada. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Survival (1 study): A before-and-after study in the USA and Canada found that sterilising some wolves (combined with trapping and removing others) did not increase caribou survival. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2573https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2573Wed, 10 Jun 2020 09:59:30 +0100Collected Evidence: Collected Evidence: Manage wetland water levels for mammal species One study evaluated the effects of managing wetland water levels for mammal species. This study was in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): A replicated, site comparison study in the USA found that managing wetland water levels to be higher in winter increased the abundance of muskrat houses. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2574https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2574Wed, 10 Jun 2020 10:49:37 +0100Collected Evidence: Collected Evidence: Remove or control competitors Two studies evaluated the effects on non-controlled mammals of removing or controlling competitors. One study was across Norway and Sweden and one was in Norway. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Reproductive success (1 study): A replicated, controlled study in Norway and Sweden found that red fox control, along with supplementary feeding, was associated with an increase in arctic fox litters. BEHAVIOUR (1 STUDY) Use (1 study): A controlled study in Norway found that where red foxes had been controlled arctic foxes were more likely to colonize. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2575https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2575Wed, 10 Jun 2020 11:11:57 +0100Collected Evidence: Collected Evidence: Create or maintain corridors between habitat patches Four studies evaluated the effects on mammals of creating or maintaining corridors between habitat patches. One study was in each of Canada, the USA, Norway and the Czech Republic. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (4 STUDIES) Use (4 studies): Four studies (three replicated) in Canada, the USA, Norway and the Czech Republic found that corridors between habitat patches were used by small mammals. Additionally, North American deermice moved further through corridors with increased corridor width and connectivity and root voles moved further in corridors of intermediate width. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2576https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2576Wed, 10 Jun 2020 11:20:07 +0100Collected Evidence: Collected Evidence: Apply fertilizer to vegetation to increase food availability Two studies evaluated the effects on mammals of applying fertilizer to vegetation to increase food availability. One study was in Canada and one was in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (2 STUDIES) Use (2 studies): Two replicated, controlled studies, in Canada and the USA, found that applying fertilizer increased the use of vegetation by pronghorns and Rocky Mountain elk. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2577https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2577Wed, 10 Jun 2020 11:48:19 +0100Collected Evidence: Collected Evidence: Provide diversionary feeding for predators One study evaluated the effects on potential prey mammals of providing diversionary feeding for predators. 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 diversionary feeding of predators appeared to increase woodland caribou calf survival. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2578https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2578Wed, 10 Jun 2020 12:20:38 +0100Collected Evidence: Collected Evidence: Sterilize non-native domestic or feral species (e.g. cats and dogs) We found no studies that evaluated the effects on mammals of sterilizing non-native domestic or feral species (e.g. cats and dogs). '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%2F2579https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2579Wed, 10 Jun 2020 12:30:16 +0100Collected Evidence: Collected Evidence: Train mammals to avoid problematic species Two studies evaluated the effects of training mammals to avoid problematic species. Both studies were in Australia. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Survival (1 study): A controlled study in Australia found that training greater bilbies to avoid introduced predators did not increase their post-release survival. BEHAVIOUR (2 STUDIES) Behaviour change (2 studies): One of two controlled studies in Australia found that greater bilbies trained to avoid introduced predators showed more predator avoidance behaviour, the second study found no difference in behaviour between trained and untrained bilbies. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2580https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2580Wed, 10 Jun 2020 12:32:50 +0100Collected Evidence: Collected Evidence: Treat disease in wild mammals Three studies evaluated the effects on mammals of treating disease in the wild. Two studies were in the USA and one was in Germany. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Condition (2 studies): A replicated study in Germany found that medical treatment of mouflons against foot rot disease healed most infected animals. A before-and-after study in the USA found that management which included vaccination of Yellowstone bison did not reduce prevalence of brucellosis. BEHAVIOUR (1 STUDY) Uptake (1 study): A study in the USA found that a molasses-based bait was readily consumed by white-tailed deer, including when it contained a dose of a disease vaccination. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2581https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2581Wed, 10 Jun 2020 12:45:23 +0100Collected Evidence: Collected Evidence: Use vaccination programme Seven studies evaluated the effects on mammals of using vaccination programmes. Three studies were in the UK and one study was in each of Belgium, Spain, Poland and Ethiopia. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (7 STUDIES) Abundance (1 study): A before-and-after study in Poland found that following an anti-rabies vaccination programme, red fox numbers increased. Condition (6 studies): Five studies (including three replicated, three controlled and two before-and-after studies) in Belgium, Spain and the UK found that following vaccination, rabies was less frequent in red foxes, numbers of Eurasian badgers infected with tuberculosis was reduced and European rabbits developed immunity to myxomatosis and rabbit haemorrhagic disease. One of the studies also found that vaccination reduced the speed and extent of infection in infected Eurasian badgers. A study in Ethiopia found that following vaccination of Ethiopian wolves, a rabies outbreak halted. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2582https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2582Wed, 10 Jun 2020 15:01:54 +0100Collected Evidence: Collected Evidence: Provide artificial refuges/breeding sites Eight studies evaluated the effects on mammals of providing artificial refuges/breeding sites. Two studies were in each of the USA, Spain and Portugal and one was in each of Argentina and Australia. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (4 STUDIES) Abundance (3 studies): Two studies (one controlled), in Spain and Portugal, found that artificial warrens increased European rabbit abundance. A replicated, randomized, controlled, before-and-after study in Argentina found that artificial refuges did not increase abundances of small vesper mice or Azara's grass mice. Survival (1 study): A study in USA found that artificial escape dens increased swift fox survival rates. BEHAVIOUR (4 STUDIES) Use (4 studies): Four studies (two replicated), in Australia, Spain, Portugal and the USA, found that artificial refuges, warrens or nest structures were used by fat-tailed dunnarts, European rabbits, and Key Largo woodrats and Key Largo cotton mice. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2583https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2583Wed, 10 Jun 2020 15:06:41 +0100Collected Evidence: Collected Evidence: Provide artificial dens or nest boxes on trees Thirty studies evaluated the effects on mammals of providing artificial dens or nest boxes on trees. Fourteen studies were in Australia, nine were in the USA, three were in the UK, one was in each of Canada, Lithuania, South Africa and Japan. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (6 STUDIES) Abundance (5 studies): Three of five controlled studies (three also replicated) in the USA, the UK, Canada and Lithuania, found that provision of artificial dens or nest boxes increased abundances of gray squirrels and common dormice. The other two studies found that northern flying squirrel and Douglas squirrel abundances did not increase. Condition (1 study): A replicated, randomized, paired sites, controlled, before-and-after study in Canada found that nest boxes provision did not increase body masses of northern flying squirrel or Douglas squirrel. BEHAVIOUR (27 STUDIES) Use (27 studies): Twenty-seven studies, in Australia, the USA, the UK, Canada, South Africa and Japan found that artificial dens or nest boxes were used by a range of mammal species for roosting and breeding. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2584https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2584Wed, 10 Jun 2020 15:48:27 +0100Collected Evidence: Collected Evidence: Eliminate highly virulent diseases early in an epidemic by culling all individuals (healthy and infected) in a defined area We found no studies that evaluated the effects on mammals of eliminating highly virulent diseases early in an epidemic by culling all individuals (healthy and infected) in a defined area. '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%2F2585https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2585Wed, 10 Jun 2020 15:54:32 +0100Collected Evidence: Collected Evidence: Cull disease-infected animals One study evaluated the effects on mammals of culling disease-infected animals. This study was in Tasmania. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Condition (1 study): A before-and-after, site comparison study in Tasmania found that culling disease-infected Tasmanian devils resulted in fewer animals with large tumours associated with late stages of the disease. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2586https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2586Wed, 10 Jun 2020 16:02:00 +0100Collected Evidence: Collected Evidence: Use drugs to treat parasites Seven studies evaluated the effects on mammals of using drugs to treat parasites. Three studies were in the USA, two were in Spain, one was in Germany and one was in Croatia. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (7 STUDIES) Survival (1 study): A randomized, replicated, controlled study the USA found that medical treatment of Rocky Mountain bighorn sheep against lungworm did not increase lamb survival. Condition (6 studies): Three of four before-and-after studies (one controlled), in Germany, the USA and Croatia, found that after administering drugs to mammals, parasite burdens were reduced in roe deer and in wild boar piglets and numbers of white-tailed deer infected were reduced. A third study found that levels of lungworm larvae in bighorn sheep faeces were reduced one month after drug treatment but not after three to seven months. One of these studies also found that the drug treatment resulted in increased body weight in roe deer fawns. A replicated, controlled, before-and-after study in Spain found that higher doses of ivermectin treated sarcoptic mange in Spanish ibex faster than lower doses, and treatment was more effective in animals with less severe infections. A replicated, before-and-after study in Spain found that after injecting Spanish ibex with ivermectin to treat sarcoptic mange a mange-free herd was established. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2587https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2587Wed, 10 Jun 2020 16:10:22 +0100Collected Evidence: Collected Evidence: Establish populations isolated from disease One study evaluated the effects on mammals of establishing populations isolated from disease. The study was in sub-Saharan Africa. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Condition (1 study): A site comparison study throughout sub-Saharan Africa found that fencing reduced prevalence of canine distemper but not of rabies, coronavirus or canine parvovirus in African wild dogs. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2588https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2588Wed, 10 Jun 2020 17:12:09 +0100Collected Evidence: Collected Evidence: Control ticks/fleas/lice in wild mammal populations Two studies evaluated the effects of controlling ticks, fleas or lice in wild mammal populations. Both studies were in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Condition (2 studies): A replicated, paired sites, controlled study in the USA found that a grain-bait insecticide product did not consistently reduce flea burdens on Utah prairie dogs. A controlled study the USA found that treating wolves with ivermectin cleared them of infestations of biting dog lice. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2589https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2589Wed, 10 Jun 2020 17:24:33 +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 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 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: Provide more small artificial breeding sites rather than fewer large sites One study evaluated the effects on mammals of providing more small artificial breeding sites rather than fewer larger sites. This study was in Spain. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): A replicated, controlled study in Spain found that smaller artificial warrens supported higher rabbit densities than did larger artificial warrens. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2595https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2595Thu, 11 Jun 2020 14:54:25 +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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