Collected 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 +0100Collected Evidence: Collected Evidence: Manage vegetation using livestock grazing Six studies evaluated the effects on mammals of managing vegetation using livestock grazing. Four studies were in the USA, one was in Norway and one was in Mexico. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): A replicated, controlled, before-and-after study in the USA found that introduction of livestock grazing increased the abundance of Stephens’ kangaroo rat after two years. BEHAVIOUR (5 STUDIES) Use (4 studies): One of four studies (three replicated controlled studies and a before-and-after study), in the USA and Norway, found that sheep-grazed pasture was used by feeding reindeer more than was ungrazed pasture. One found mixed effects on Rocky Mountain elk use of grazed plots and another found no response of Rocky Mountain elk to spring cattle grazing. The forth study found cattle grazing to increase the proportion of rough fescue biomass utilized by elk in the first, but not second winter after grazing. Behaviour change (1 study): A replicated, paired sites study in Mexico found that in pastures grazed by cattle, Tehuantepec jackrabbits spent more time feeding than they did in pastures not grazed by cattle. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2545https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2545Tue, 09 Jun 2020 09:12:59 +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: Replant vegetation We found no studies that evaluated the effects on mammals of replanting vegetation. '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%2F2549https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2549Tue, 09 Jun 2020 10:09:32 +0100Collected Evidence: Collected Evidence: Remove vegetation by hand/machine Twenty studies evaluated the effects on mammals of removing vegetation by hand or machine. Eleven studies were in the USA, and one each was in Canada, South Africa, Israel, Norway, Portugal, France, Spain, the Netherlands and Thailand. COMMUNITY RESPONSE (1 STUDY) Richness/diversity (1 study): A site comparison study in the USA found that mechanically clearing trees within woodland reduced small mammal diversity. POPULATION RESPONSE (12 STUDIES) Abundance (11 studies): Eight of 11 site comparison or controlled studies (nine of which were replicated), in the USA, Israel, Portugal, Spain and the Netherlands, found that clearing woody vegetation or herbaceous and grassland vegetation benefitted target mammals. Population or density increases were recorded for small mammals, European rabbits and Stephens’ kangaroo rat while black-tailed prairie dog and California ground squirrel colonies were larger or denser and Utah prairie dog colonies established better than in uncleared areas. Two studies found mixed results of clearing woody vegetation, with hazel dormouse abundance declining, then increasing and small mammal abundance increasing, then declining in both cleared and uncleared plots alike. One study found no effect of scrub clearance from sand dunes on habitat specialist small mammals. Survival (1 study): A replicated, site comparison study in the USA found that mechanical disturbance of woody vegetation within forest (combined with reseeding, follow-up herbicide application and further seeding) increased overwinter survival of mule deer fawns. BEHAVIOUR (8 STUDIES) Use (8 studies): Four of seven studies (of which six were site comparisons or controlled), in the USA, Canada, Norway, France and Thailand, found that areas cleared of woody vegetation or herbaceous and grassland vegetation were utilized more by mule deer, reindeer, mouflon and gaur. One study found that clearing woody vegetation promoted increased use by white-tailed deer in some but not all plots, one found that it did not increase use by mule deer and one found that carrying out a second clearance on previously cleared plots did not increase use by white-tailed deer. A before-and-after study in South Africa found that clearing woody vegetation from shrubland increased wildebeest and zebra abundance following subsequent burning but not when carried out without burning whilst other mammals did not show consistent responses. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2550https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2550Tue, 09 Jun 2020 10:10:24 +0100Collected Evidence: Collected Evidence: Retain/provide migration corridors We found no studies that evaluated the effects on mammals of retaining or providing migration corridors. ‘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%2F2551https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2551Tue, 09 Jun 2020 10:34:36 +0100Collected Evidence: Collected Evidence: Protect habitat along elevational gradients We found no studies that evaluated the effects on mammals of protecting habitat along elevational gradients. ‘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%2F2552https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2552Tue, 09 Jun 2020 10:36:21 +0100Collected Evidence: Collected Evidence: Translocate animals from source populations subject to similar climatic conditions One study evaluated the effects of translocating mammals from source populations subject to similar climatic conditions. This study was in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Reproductive success (1 study): A study in the USA found that bighorn sheep translocated from populations subject to a similar climate to the recipient site reared more offspring than did those translocated from milder climatic areas. BEHAVIOUR (0 STUDIES)  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2553https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2553Tue, 09 Jun 2020 10:38:01 +0100Collected Evidence: Collected Evidence: Provide dams/water holes during drought We found no studies that evaluated the effects on mammals of providing dams or water holes during drought. ‘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%2F2554https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2554Tue, 09 Jun 2020 10:44:26 +0100Collected Evidence: Collected Evidence: Apply water to vegetation to increase food availability during drought One study evaluated the effects on mammals of applying water to vegetation to increase food availability during drought. This study was in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (1 STUDY) Use (1 study): A controlled, before-and-after study in the USA found that watering scrub during drought increased its use by adult Sonoran pronghorns for feeding. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2555https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2555Tue, 09 Jun 2020 10:47:58 +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: Remove flood water We found no studies that evaluated the effects on mammals of removing flood water. ‘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%2F2557https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2557Tue, 09 Jun 2020 10:52:09 +0100Collected Evidence: Collected Evidence: Install one-way gates or other structures to allow wildlife to leave roadways Seven studies evaluated the effects on mammals of installing one-way gates or other structures to allow wildlife to leave roadways. All seven studies were in the USA. COMMUNITY RESPONSE (5 STUDIES) Survival (5 studies): Two before-and-after studies (one replicated), in the USA, found that barrier fencing with one-way gates reduced deer-vehicle collisions. One of two studies (one before-and-after and one replicated, controlled), in the USA, found that barrier fencing with escape gates along roads with one or more underpasses reduced moose-vehicle collisions, whilst the other found no reduction in total mammal road casualty rates. A replicated, controlled, before-and-after study in USA found that earth escape ramps reduced mammal road mortalities. POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (4 STUDIES) Use (4 studies): One of two studies (one replicated) in the USA, found that one-way gates allowed mule deer to escape when trapped along highways with barrier fencing, whilst the other found that a small proportion used one-way gates. A replicated, controlled, before-and-after study in the USA found that earth escape ramps were used more often than were one-way escape gates to enable deer to escape highways with barrier fencing. A replicated, controlled study in the USA found that barrier fencing with escape gates and underpasses facilitated road crossings by a range of mammals. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2558https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2558Tue, 09 Jun 2020 11:28:18 +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 +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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