Collected Evidence: Collected Evidence: Provide badger gates We have captured no evidence for the effects of providing badger gates on farmland wildlife. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F84https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F84Mon, 24 Oct 2011 21:23:17 +0100Collected Evidence: Collected Evidence: Provide bat boxes, bat grilles, improvements to roosts We have captured no evidence for the effects of providing bat boxes, bat grilles or improvements to roosts on farmland wildlife. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F95https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F95Mon, 24 Oct 2011 21:39:48 +0100Collected Evidence: Collected Evidence: Provide buffer strips alongside water courses (rivers and streams) Three studies (including one replicated site comparison) from the Netherlands and the UK reported that the provision of riparian buffer strips had a positive influence on plant, invertebrate and bird diversity or abundance, and supported vegetation associated with habitats preferred by water voles. Two replicated site comparison studies from France and Ireland found that the provision of riparian buffer strips on farms did not result in an increase in the number of plant species when compared to farms without buffer strips. One replicated site comparison study found ground beetle diversity was higher in grazed riparian zones and narrow fenced strips than in wide riparian buffer strips. However the ground beetle assemblages in wide riparian buffer strips were more distinct from the adjacent pasture field assemblages than either the grazed riparian zones or narrow fenced strips. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F120https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F120Tue, 01 Nov 2011 21:03:36 +0000Collected Evidence: Collected Evidence: Provide bird feeding materials to families with young childrenA single replicated before-and-after study from the USA found that most children involved in a programme providing families with bird food increased their knowledge of birds, but there was no significant change in environmental attitudes.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F163https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F163Sat, 19 May 2012 20:07:24 +0100Collected Evidence: Collected Evidence: Provide buffer strips along rivers and streams We did not find any evidence describing the impact of riparian strips on reducing water pollution and how this affected bird populations. However, riparian strips also provide valuable habitats in their own right. Studies describing the use of riparian strips by birds are described in ‘Habitat restoration and creation’. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F463https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F463Wed, 29 Aug 2012 16:08:57 +0100Collected Evidence: Collected Evidence: Provide buffer strips around in-field ponds We found no evidence describing the effect of buffer strips around in-field ponds on pollution levels and bird populations. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F464https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F464Wed, 29 Aug 2012 16:09:56 +0100Collected Evidence: Collected Evidence: Provide artificial nesting sites for woodpeckers Four studies from the USA found local increases in red-cockaded woodpecker Picoides borealis populations or the successful colonisation of new areas following the installation of ‘cavity inserts’ (described above). One study also found that the productivity of birds using the inserts was significantly higher than the regional average. Two studies from the USA found that red-cockaded woodpeckers Picoides borealis used cavity inserts, in one case more frequently than making their own holes or using natural cavities. One study from the USA found that woodpeckers roosted, but did not nest, frequently in nest boxes. Five studies from the USA found that some woodpeckers excavated holes in artificial snags but only ever roosted in excavated holes or in nest boxes provided. A small study in the USA found that modifying artificial nests to allow easy access did not alter the behaviour of birds using them.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F496https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F496Tue, 04 Sep 2012 12:45:28 +0100Collected Evidence: Collected Evidence: Provide calcium supplements to increase survival or reproductive success Eight studies from across the world, including a literature review from across the world found evidence for positive effects of calcium supplementation on several bird species. Positive effects included lower incidence of bone disease, higher fledging succes, larger broods, higher quality eggs or chicks and better physical condition of female parents. Not all species reacted similarly. Six studies including a literature review did not find any evidence for increased reproductive success in at least one of the species supplied with supplementary calcium. One replicated study from Europe found that birds took calcium supplied, and birds at polluted sites took more than those at cleaner sites. The effects on fitness were not monitored.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F559https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F559Sun, 23 Sep 2012 15:19:49 +0100Collected Evidence: Collected Evidence: Provide artificial subterranean bat roosts to replace roosts in reclaimed mines We found no studies that evaluated the effects of providing artificial subterranean bat roosts to replace roosts in reclaimed mines on bat populations. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F974https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F974Fri, 20 Dec 2013 12:43:16 +0000Collected Evidence: Collected Evidence: Provide artificial subterranean bat roosts to replace roosts in disturbed caves We found no studies that evaluated the effects of providing artificial subterranean bat roosts to replace roosts in disturbed caves on bat populations. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1005https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1005Fri, 20 Dec 2013 17:19:47 +0000Collected Evidence: Collected Evidence: Provide bat boxes for roosting bats Forty-four studies evaluated the effects of providing bat boxes for roosting bats on bat populations. Twenty-seven studies were in Europe, nine studies were in North America, four studies were in Australia, two studies were in South America, and one study was a worldwide review. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (44 STUDIES) Uptake (9 studies): Nine replicated studies in Europe and the USA found that the number of bats using bat boxes increased by 2–10 times up to 10 years after installation. Use (43 studies): Forty-one of 43 studies (including 34 replicated studies and two reviews) in Europe, the USA, South America, and Australia found that bats used bat boxes installed in forest or woodland, forestry plantations, farmland, pasture, wetlands, urban areas and buildings, bridges, underpasses or unknown habitats. The other two studies in the USA and UK found that bats displaced from buildings did not use any of 43 bat houses of four different designs or 12 heated bat boxes of one design. One review of 109 studies across Europe, North America and Asia found that 72 bat species used bat boxes, although only 18 species commonly used them, and 31 species used them as maternity roosts. Twenty-two studies (including 17 replicated studies, one before-and-after study and two reviews) found bats occupying less than half of bat boxes provided (0–49%). Nine replicated studies found bats occupying more than half of bat boxes provided (54–100%). OTHER (23 STUDIES) Bat box design (16 studies): Three studies in Germany, Portugal and Australia found that bats used black bat boxes more than grey, white or wooden boxes. One of two studies in Spain and the USA found higher occupancy rates in larger bat boxes. One study in the USA found that bats used both resin and wood cylindrical bat boxes, but another study in the USA found that resin bat boxes became occupied more quickly than wood boxes. One study in the UK found higher occupancy rates in concrete than wooden bat boxes. One study in the USA found that Indiana bats used rocket boxes more than wooden bat boxes or bark-mimic roosts. One study in Spain found that more bats occupied bat boxes that had two compartments than one compartment in the breeding season. One study in Lithuania found that bat breeding colonies occupied standard and four/five chamber bat boxes and individuals occupied flat bat boxes. Four studies in the USA, UK, Spain and Australia found bats selecting four of nine, three of five, three of four and one of five bat box designs. One study in the UK found that different bat box designs were used by different species. One study in Costa Rica found that bat boxes simulating tree trunks were used by 100% of bats and in group sizes similar to natural roosts. Bat box position (11 studies): Three studies in Germany, Spain and the USA found that bat box orientation and/or the amount of exposure to sunlight affected bat occupancy, and one study in Spain found that orientation did not have a significant effect on occupancy. Two studies in the UK and Italy found that bat box height affected occupancy, and two studies in Spain and the USA found no effect of height. Two studies in the USA and Spain found higher occupancy of bat boxes on buildings than on trees. One study in Australia found that bat boxes were occupied more often in farm forestry sites than in native forest, one study in Poland found higher occupancy in pine relative to mixed deciduous stands, and one study in Costa Rica found higher occupancy in forest fragments than in pasture. One study in the USA found higher occupancy rates in areas where bats were known to roost prior to installing bat boxes. One review in the UK found that bat boxes were more likely to be occupied when a greater number of bat boxes were installed across a site. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1024https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1024Fri, 20 Dec 2013 18:17:59 +0000Collected Evidence: Collected Evidence: Provide better equipment (e.g. guns) to anti-poaching ranger patrols One before-and-after study in the Democratic Republic of Congo and Rwanda found that gorilla populations increased after anti-poaching guard were provided with better equipment, alongside other interventions. One study in Uganda found that no gorillas were killed for 21 months after game guards were provided with better equipment, alongside other interventions. One before-and-after study in Rwanda found that the number of immature gorillas increased and the number of snares decreased after anti-poaching patrols were supplied with better equipment, alongside other interventions. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1476https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1476Tue, 17 Oct 2017 17:22:29 +0100Collected Evidence: Collected Evidence: Provide artificial water sources One before-and-after trial in Brazil found that a minority of reintroduced golden lion tamarins survived over seven years when provided with supplementary water, alongside other interventions. One before-and-after study in Madagascar found that a minority of reintroduced black-and-white ruffed lemurs survived for five years despite being provided with supplementary water, alongside other interventions. A before-and-after study in South Africa found that a minority of vervet monkeys had survived for 10 months when provided with supplementary water, alongside other interventions. A before-and-after study in Gabon found that a majority of western lowland gorillas survived for at least nine months while being provided with supplementary water, alongside other interventions. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1531https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1531Thu, 19 Oct 2017 10:26:56 +0100Collected Evidence: Collected Evidence: Provide artificial shelters Five studies examined the effects of providing artificial shelters on subtidal benthic invertebrates. Three studies were in the Caribbean Sea (Mexico); one in Florida Bay and one in the Florida Keys (USA).   COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Lobster abundance (2 studies): Two replicated, controlled, before-and-after studies in the Caribbean Sea found that abundance of lobsters either increased in plots with artificial shelters but not in plots without, or increased in all plots but more so in plots with artificial shelters than those without. Lobster condition (1 study): One replicated, controlled, before-and-after study in the Caribbean Sea found that lobsters in plots with artificial shelters were bigger than in plots without. BEHAVIOUR (3 STUDIES) Use (3 studies): Three replicated studies (two controlled) in Florida Bay, the Florida Keys, and the Caribbean Sea, found that artificial shelters were occupied by lobsters and molluscs, that occupancy by lobsters varied with artificial shelter designs, that lobsters occupied artificial shelters more than natural ones (crevices), and that lobsters occupying artificial shelters were larger, had greater nutritional condition, and had similar sex ratio and survival rate, compared to lobsters occupying natural shelters. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2257https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2257Wed, 23 Oct 2019 10:13:10 +0100Collected Evidence: Collected Evidence: Provide artificial shelters following release We found no studies that evaluated the effects of providing artificial shelters following the release of species on their populations.   ‘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%2F2272https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2272Wed, 23 Oct 2019 12:48:42 +0100Collected Evidence: Collected Evidence: Provide diversionary feeding for mammals to reduce nuisance behaviour and human-wildlife conflict Three studies evaluated the effects of providing diversionary feeding for mammals to reduce nuisance behaviour and human-wildlife conflict. Two studies were in the USA and one was in Slovenia. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (1 STUDY) Uptake (1 study): A site comparison study in Slovenia found that 22-63% of the estimated annual energy content of the diet of brown bears comprised provided diversionary food. OTHER (2 STUDIES) Human-wildlife conflict (2 studies): Two before-and-after studies (one also a site comparison) in the USA found that diversionary feeding reduced nuisance behaviour by black bears. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2323https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2323Wed, 20 May 2020 10:24:28 +0100Collected Evidence: Collected Evidence: Provide diversionary feeding to reduce crop damage by mammals to reduce human-wildlife conflict Six studies evaluated the effects of providing diversionary feeding to reduce crop damage by mammals to reduce human-wildlife conflict. Three studies were in Canada and one was in each of France, Spain and Austria. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (6 STUDIES) Human-wildlife conflict (6 studies): Three of six studies (including four controlled and one before-and-after study) in Canada, France, Spain and Austria found that diversionary feeding reduced damage by red squirrels to pine trees and European rabbits to grape vines, and resulted in fewer red deer using vulnerable forest stands. Two studies found that diversionary feeding did not reduce damage by voles to apple trees or wild boar to grape vines. One study found mixed results on damage by voles to crabapple trees depending on the food provided. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2457https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2457Tue, 02 Jun 2020 11:18:00 +0100Collected Evidence: Collected Evidence: Provide artificial waterholes in dry season Three studies evaluated the effects on mammals of providing artificial waterholes in the dry season. One study was in South Africa, one was in Tanzania and one was in Jordan. COMMUNITY RESPONSE (1 STUDY) Richness/diversity (1 study): A site comparison study in Tanzania found that artificial waterholes were used by a similar number of large mammal species as was a natural waterhole. POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (2 STUDIES) Use (2 studies): A study in South Africa found that areas around artificial waterholes were used more by eight out of 13 mammalian herbivore species than was the wider landscape. A study in Jordan found that artificial waterholes were used by striped hyenas. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2484https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2484Thu, 04 Jun 2020 12:15:59 +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: 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: 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: 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 shade for individuals Two studies evaluated the effects of providing artificial shade for individuals on reptile populations. One study was in Australia and one was in Canada. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (2 STUDIES) Use (2 studies): One replicated, randomized study in Australia found that shaded, artificial rocky outcrops were used less often than unshaded ones by velvet geckos. One study in Canada found that coverboards were used by northern pacific rattlesnakes in the year they were installed, but not a decade later. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3641https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3641Thu, 09 Dec 2021 15:17:20 +0000Collected Evidence: Collected Evidence: Provide artificial shade for nests or nesting sites Four studies evaluated the effects of providing artificial shade for nests or nesting sites on reptile populations. Two studies were in the USA and one was in each of Panama, and Australia. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (3 STUDIES) Reproductive success (3 studies): One of two controlled studies (including one replicated study) in Panama and Australia found that shaded leatherback turtles nests had higher hatching success than unshaded nests. The other study found that shaded and unshaded loggerhead turtle nests had similar hatching success. One replicated, controlled study in the USA found that relocating diamondback terrapin nests to artificial nest mounds and providing shade had mixed effects on hatchling success. Condition (2 studies): One of two controlled studies (including one replicated study) in Panama and Australia found that greater shade cover resulted in smaller hatchlings for leatherback turtles. The other study found that shading loggerhead turtle nests had mixed effects on hatchling size and crawl speed. BEHAVIOUR (0 STUDIES) OTHER (2 STUDIES) Offspring sex ratio (2 studies): One of two controlled studies (including one before-and-after study) in Panama and the USA found that shading leatherback turtle nests resulted in fewer female hatchlings compared to unshaded nests. The other study found that shaded and unshaded Agassiz’s desert tortoise nests produced a similar sex ratio of hatchlings. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3643https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3643Thu, 09 Dec 2021 15:28:57 +0000Collected Evidence: Collected Evidence: Provide buffer strips to reduce pesticide and nutrient run-off into margins, waterways and ponds One study evaluated the effects on butterflies and moths of providing buffer strips to reduce pesticide and nutrient run-off into margins, waterways and ponds. This study was in the UK. COMMUNITY RESPONSE (1 STUDY) Richness/diversity (1 study): One replicated, paired, site comparison study in the UK found that margins next to water bodies managed with restrictions on fertilizer and pesticide use (as well as restrictions on mowing and grazing) had a similar species richness of moths to conventionally managed margins. POPULATION RESPONSE (1 STUDY) Abundance (1 study): One replicated, paired, site comparison study in the UK found that margins next to water bodies managed with restrictions on fertilizer and pesticide use (as well as restrictions on mowing and grazing) had a greater abundance of moths than conventionally managed margins. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3894https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3894Tue, 09 Aug 2022 13:15:49 +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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