Collected Evidence: Collected Evidence: Provide live natural prey to captive mammals to foster hunting behaviour before release Three studies evaluated the effects of providing live natural prey to captive mammals to foster hunting behaviour before release. One study was in Spain, one was in the USA and one was in Botswana. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Survival (2 studies): Two studies in Spain and Botswana found that a rehabilitated Iberian lynx and wild-born but captive-reared orphaned cheetahs and leopards that were provided with live natural prey in captivity survived for between at least three months and 19 months after release. BEHAVIOUR (1 STUDY) Behaviour change (1 study): A controlled study in the USA found that captive-bred black-footed ferrets fed on live prairie dogs took longer to disperse after release but showed greater subsequent movements than did ferrets not fed with live prairie dogs. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2518https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2518Mon, 08 Jun 2020 09:14:03 +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: Train captive-bred mammals to avoid predators Two studies evaluated the effects of training captive-bred mammals to avoid predators. One study was in Australia and one was in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Survival (1 study): A randomized, controlled study in the USA found that training captive-born juvenile black-tailed prairie dogs, by exposing them to predators, increased post-release survival. BEHAVIOUR (1 STUDY) Behaviour change (1 study): A before-and-after study in Australia found that rufous hare-wallabies could be conditioned to become wary of potential predators. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2520https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2520Mon, 08 Jun 2020 09:30:41 +0100Collected Evidence: Collected Evidence: Release captive-bred mammals into fenced areas Fourteen studies evaluated the effects of releasing captive-bred mammals into fenced areas. Nine studies were in Australia and one each was in Jordan, South Africa, the USA, Saudi Arabia and Senegal. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (14 STUDIES) Abundance (5 studies): Four studies (one replicated) and a review in Australia, Jordan and Senegal found that after releasing captive-bred animals into fenced areas, a population of burrowing bettongs increased, a population of Arabian oryx increased six-fold in 12 years, a population of dorcas gazelle almost doubled over four years, three populations of eastern barred bandicoot initially increased and abundance of eastern barred bandicoots increased. Reproductive success (6 studies): Four studies and a review in South Africa, Australia, Saudi Arabia and Senegal found that following release of captive-bred animals into fenced areas (in some cases with other associated management), African wild dogs, three populations of eastern barred bandicoot, dorcas gazelle and most female black-footed rock-wallabies reproduced, and Arabian gazelles started breeding in the year following the first releases. A study in Australia found that four of five mammal populations released into a predator-free enclosure and one released into a predator-reduced enclosure reproduced, whereas two populations released into an unfenced area with ongoing predator management did not survive to reproduce. Survival (10 studies): A study in Australia found that four of five mammal populations released into a predator-free enclosure and one population released into a predator-reduced enclosure survived, whereas two populations released into an unfenced area with ongoing predator management did not. Six studies (one controlled before-and-after study and two replicated studies) in Australia and the USA found that following release of captive-bred animals into fenced areas (in some cases with other associated management), a burrowing bettong population, three eastern barred bandicoot populations and over half of black-footed rock-wallabies survived between one and eight years, most captive-bred hare-wallabies survived at least two months, at least half of black-footed ferrets survived more than two weeks, and bandicoots survived at five of seven sites up to three years after the last release. One study in Australia found that following release into fenced areas, a captive-bred population of red-tailed phascogales survived for less than a year. A study in South Africa found that captive-bred African wild dogs released into fenced reserves in family groups had high survival rates. A randomized, controlled study in Australia found that captive-bred eastern barred bandicoots released into a fenced reserve after time in holding pens had similar post-release survival compared to bandicoots released directly from captivity. Condition (1 study): A randomized, controlled study in Australia found that captive-bred eastern barred bandicoots released into a fenced reserve after time in holding pens had similar post-release body weight compared to those released directly from captivity. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2521https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2521Mon, 08 Jun 2020 09:55:37 +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 overpasses over roads/railways Twenty-two studies evaluated the effects on mammals of installing overpasses over roads or railways. Seven studies were in Canada, three were in Spain, three were in Australia, two were in Sweden, one each was in the Netherlands, Germany, Croatia and the USA, and three (including two reviews) were conducted across multiple countries. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (4 STUDIES) Survival (4 studies): Four studies (including three before-and-after studies), in Canada, Sweden and Australia, found that overpasses (in combination with roadside fencing) reduced collisions between vehicles and mammals. In two of these studies, data from overpasses and underpasses were combined for analysis. BEHAVIOUR (21 STUDIES) Use (21 studies): Nineteen studies, in North America, Europe and Australia, found that overpasses were used by mammals. A wide range of mammals was reported using overpasses, including rodents and shrews, rabbits and hares, carnivores, ungulates, bears, marsupials and short-beaked echidna. A review of crossing structures in Australia, Europe and North America found that overpasses were used by a range of mammals, particularly larger mammal species. A global review of crossing structures (including overpasses) found that all studies reported that the majority of crossings were used by wildlife. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2526https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2526Mon, 08 Jun 2020 13:33:46 +0100Collected Evidence: Collected Evidence: Provide supplementary food during/after release of captive-bred mammals Fifteen studies evaluated the effects of providing supplementary food during/after release of captive-bred mammals. Four studies were in Australia, two were in each of the USA, China and Argentina, and one was in each of Poland, the UK, Oman and Saudi Arabia. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (14 STUDIES) Abundance (5 studies): Four studies (one replicated, one before-and-after study) and one review in Poland, Oman, China and Australia found that following provision of supplementary food (and in one case water) to released captive-bred animals, populations of European bison increased more than six-fold over 20 years, Arabian oryx increased over 14 years, eastern-barred bandicoots increased for the first five years before declining, Père David's deer increased more than six-fold over 12 years and Przewalski’s horses (enclosed in winter) increased over 11 years. Reproductive success (9 studies): Eight studies (including two replicated and one before-and-after study) and one review in Poland, the UK, China, the USA, Australia and Saudi Arabia found that following the provision of supplementary food (and in one case water or artificial nests) after release of captive-bred animals, some from holding pens, European bison, European otters, Père David's deer, eastern-barred bandicoots, Przewalski’s horses and some captive-bred red wolves successfully reproduced, Arabian gazelles started breeding in the year following releases and sugar gliders established a breeding population. Survival (6 studies): Four of six studies (one controlled, before-and-after study) in the UK, USA, Argentina and Australia found that following the provision of supplementary food (and in one case water or nest boxes) after release of captive-bred animals, many from holding pens, 19% of red wolves survived for at least seven years, Eurasian otters survived for at least two years, over half the giant anteaters (some rehabilitated) survived for at least six months and hare-wallabies survived at least two months. Two of the studies found that red-tailed phascogales survived for less than a year and most Mexican wolves survived less than eight months. BEHAVIOUR (1 STUDY) Behaviour change (1 study): A controlled study in Argentina found that after being provided with supplementary food and kept in holding pens, released captive-bred giant anteaters were less nocturnal in their activity patterns than released wild-born rehabilitated individuals. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2527https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2527Mon, 08 Jun 2020 14:23:58 +0100Collected Evidence: Collected Evidence: Remove/control non-native mammals within a fenced area One study evaluated the effects on native mammals of removing or controlling non-native mammals within a fenced area. This study was in Australia. COMMUNITY RESPONSE (1 STUDY) Richness/diversity (1 study): A site comparison study in Australia found that in a fenced area where invasive cats, red foxes and European rabbits were removed, native mammal species richness was higher than outside the fenced area. POPULATION RESPONSE (1 STUDY) Abundance (1 study): A site comparison study in Australia found that in a fenced area where invasive cats, red foxes and European rabbits were removed, native mammals overall and two out of four small mammal species were more abundant than outside the fenced area. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2528https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2528Mon, 08 Jun 2020 14:51:07 +0100Collected Evidence: Collected Evidence: Remove/control non-native plants Two studies evaluated the effects on mammals of removing or controlling non-native invasive plants. Both studies were in the USA. COMMUNITY RESPONSE (1 STUDY) Richness/diversity (1 study): A replicated study in the USA found that control of introduced saltcedar did not change small mammal species richness. POPULATION RESPONSE (1 STUDY) Abundance (1 study): A site comparison study in the USA found that partial removal of velvet mesquite did not increase abundances of six mammal species. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2529https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2529Mon, 08 Jun 2020 15:23:29 +0100Collected Evidence: Collected Evidence: Control non-native/problematic plants to restore habitat We found no studies that evaluated the effects on mammals of controlling invasive or problematic plants to restore 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%2F2530https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2530Mon, 08 Jun 2020 16:20:23 +0100Collected Evidence: Collected Evidence: Reintroduce top predators to suppress and reduce the impacts of smaller non-native predator and prey species We found no studies that evaluated the effects on mammals of reintroducing top predators to suppress and reduce the impacts of smaller non-native predator and prey species. '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%2F2531https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2531Mon, 08 Jun 2020 16:22:00 +0100Collected Evidence: Collected Evidence: Control non-native prey species to reduce populations and impacts of non-native predators We found no studies that evaluated the effects on mammals of controlling non-native prey species to reduce populations and impacts of non-native predators. '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%2F2532https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2532Mon, 08 Jun 2020 16:23:17 +0100Collected Evidence: Collected Evidence: Provide artificial refuges for prey to evade/escape non-native predators We found no studies that evaluated the effects on mammals of providing artificial refuges for prey to evade/escape non-native predators. '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%2F2533https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2533Mon, 08 Jun 2020 16:24:27 +0100Collected Evidence: Collected Evidence: Remove/control non-native species that could interbreed with native species We found no studies that evaluated the effects on mammals of removing or controlling non-native species that could interbreed with native species. '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%2F2534https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2534Mon, 08 Jun 2020 16:26:23 +0100Collected Evidence: Collected Evidence: Modify traps used in the control/eradication of non-native species to avoid injury of non-target mammal One study evaluated the effects of modifying traps used in the control or eradication of non-native species to avoid injury of non-target mammals. This study was in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Condition (1 study): A before-and-after study in the USA found that modifying traps used for catching non-native mammals reduced moderate but not severe injuries among incidentally captured San Nicolas Island foxes. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2535https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2535Mon, 08 Jun 2020 16:30:52 +0100Collected Evidence: Collected Evidence: Use conditioned taste aversion to prevent non-target species from entering traps One study evaluated the effects on mammals of using conditioned taste aversion to prevent non-target species from entering traps. This study was in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (1 STUDY) Behaviour change (1 study): A replicated, controlled study in the USA found that using bait laced with lithium chloride reduced the rate of entry of San Clemente Island foxes into traps set for feral cats. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2536https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2536Mon, 08 Jun 2020 16:41:53 +0100Collected Evidence: Collected Evidence: Use reward removal to prevent non-target species from entering traps One study evaluated the effects on mammals of using reward removal to prevent non-target species from entering traps. This study was in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (1 STUDY) Behaviour change (1 study): A replicated, controlled study in the USA found that when reward removal was practiced, the rate of San Clemente Island fox entry into traps set for feral cats was reduced. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2537https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2537Mon, 08 Jun 2020 16:50:53 +0100Collected Evidence: Collected Evidence: Reduce pesticide or fertilizer use Three studies evaluated the effects on mammals of reducing pesticide, herbicide or fertilizer use. Two studies were in the UK, one was in Italy and one was in Argentina. COMMUNITY RESPONSE (1 STUDY) Richness/diversity (1 study): A replicated, site comparison study in Argentina found that farming without pesticides or fertilizers did not increase small mammal species richness in field margins. POPULATION RESPONSE (2 STUDIES) Abundance (2 studies): One of two site comparison studies, in the UK and Italy, found that reducing pesticide or fertilizer use, by farming organically, increased wood mouse abundance. The other study found that it did not increase European hare abundance. BEHAVIOUR (1 STUDY) Use (1 study): A replicated, site comparison study in Argentina found that farming without pesticides or fertilizers did not increase small mammal use of field margins. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2539https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2539Mon, 08 Jun 2020 17:16:27 +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: Establish riparian buffers We found no studies that evaluated the effects on mammals of establishing riparian buffers. ‘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%2F2541https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2541Mon, 08 Jun 2020 17:51:25 +0100Collected Evidence: Collected Evidence: Translocate mammals away from site contaminated by oil spill One study evaluated the effects of translocating mammals away from a site contaminated by oil spill. This study was in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Survival (1 study): A study in the USA found that after being translocated in a trial of responses to a hypothetical pollution incident, most sea-otters survived for the duration of monitoring. BEHAVIOUR (1 STUDY) Behaviour change (1 study): A study in the USA found that after being translocated in a trial of responses to a hypothetical pollution incident, most sea-otters did not return to their capture location. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2542https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2542Mon, 08 Jun 2020 20:32:49 +0100Collected Evidence: Collected Evidence: Remove topsoil that has had fertilizer added to mimic low nutrient soil We found no studies that evaluated the effects on mammals of removing topsoil that has had fertilizer added to mimic low nutrient soil. '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%2F2544https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2544Tue, 09 Jun 2020 09:01:30 +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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