Collected 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: Legally protect bat species We found no studies that evaluated the effects of legally protecting bat species 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%2F2037https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2037Wed, 05 Dec 2018 18:29:39 +0000Collected Evidence: Collected Evidence: Regularly clean bat boxes to increase occupancy We found no studies that evaluated the effects of regularly cleaning artificial bat roosts to increase occupancy 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%2F2038https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2038Wed, 05 Dec 2018 18:31:05 +0000Collected Evidence: Collected Evidence: Release captive-bred bats We found no studies that evaluated the effects of releasing captive-bred bats 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%2F2039https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2039Wed, 05 Dec 2018 18:32:17 +0000Collected Evidence: Collected Evidence: Manage microclimate of artificial bat roosts Three studies evaluated the effects of managing the microclimate of artificial bat roosts on bat populations. Two studies were in the UK and one in Spain. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): One before-and-after study in Spain found more bats in two artificial roosts within buildings after they had been modified to reduce internal roost temperatures. BEHAVIOUR (2 STUDIES) Use (2 studies): One replicated, before-and-after study in the UK found that heated bat boxes were used by common pipistrelle bats at one of seven sites, but none were used by maternity colonies. One replicated study in the UK found that none of the 12 heated bat boxes installed within churches were used by displaced Natterer’s bats. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2052https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2052Fri, 07 Dec 2018 19:21:01 +0000
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What Works in Conservation

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