Collected Evidence: Collected Evidence: Install and maintain cave gates to restrict public access Eleven studies evaluated the effects of installing cave gates on bat populations. Six studies were in the USA and five studies were in Europe. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (7 STUDIES) Abundance (7 studies): Three of four before-and-after studies (including one replicated study and one controlled study) in the Netherlands, the USA, Spain and Turkey found more or similar numbers of bats in caves and a bunker after gates were installed to restrict public access. The other study found fewer bats in caves after gates were installed. Two before-and-after studies in the USA and Spain found more bats within two caves after the size of the gated entrances were increased. One replicated, before-and-after study in the USA found that installing cave gates resulted in population increases or decreased rates of decline for 13 of 20 colonies of Indiana bat. One replicated, site comparison study in Spain found no difference in the population growth rates of bats roosting in caves with and without cave gates. Condition (1 study): One site comparison study in the USA found that bats hibernating in a cave with a wall and gate over the entrance lost more body mass than bats in a nearby unmodified cave. BEHAVIOUR (5 STUDIES)   Use (1 study): One replicated, site comparison study in Spain found no difference in the occupancy rates of bats roosting in caves with and without cave gates. Behaviour change (4 studies): One replicated, controlled, before-and-after and site comparison study in the USA found that bats at cave entrances circled more and entered caves less after gates were installed. One replicated study in the USA found that bats flew through gates with a funnel design more frequently than gates with a round bar or angle iron design. One randomized, controlled, before-and-after study in the UK found that fewer bats flew through cave gates when the spacing between horizontal bars was reduced. One before-and-after study in the USA found that significantly fewer bats emerged from a cave with a gate installed compared with a cave with a fence. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F999https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F999Fri, 20 Dec 2013 17:07:52 +0000Collected Evidence: Collected Evidence: Restore and maintain microclimate in modified caves We found no studies that evaluated the effects of restoring and maintaining the microclimate in modified caves for roosting 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%2F1001https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1001Fri, 20 Dec 2013 17:14:49 +0000Collected Evidence: Collected Evidence: Impose restrictions on cave visits Four studies evaluated the effects of imposing restrictions on cave visits on bat populations. One study was in each of the USA, Canada, Madagascar, and Turkey. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Abundance (2 studies): Two before-and-after studies in Canada and Turkey found that bat populations within caves increased after restrictions on cave visitors were imposed. BEHAVIOUR (2 STUDIES) Behaviour change (2 studies): One study in the USA found that reducing the number of people within cave tour groups did not have a significant effect on the number of take-offs, landings or overall activity (bat movements) of a cave myotis colony roosting within the cave. One study in Madagascar found that increasing visitor approach distances, along with avoiding direct illumination of bats, reduced the alertness and number of take-offs of Madagascan rousettes during experimental cave tours. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1002https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1002Fri, 20 Dec 2013 17:17:00 +0000Collected Evidence: Collected Evidence: Inform the public of ways to reduce disturbance to bats in caves We found no studies that evaluated the effects of informing the public of ways to reduce disturbance to bats in 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%2F1003https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1003Fri, 20 Dec 2013 17:18:13 +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: Retain bat access points to caves We found no studies that evaluated the effects of retaining bat access points to 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%2F1990https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1990Wed, 05 Dec 2018 11:13:33 +0000Collected Evidence: Collected Evidence: Install fencing around cave entrances to restrict public access Two studies evaluated the effects of installing fencing around cave entrances on bat populations. One study was in the USA and one study was in Spain. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): One replicated, site comparison study in Spain found no difference in the population growth rates of bats roosting in caves with and without fencing or gates installed. BEHAVIOUR (2 STUDIES)   Use (1 study): One replicated, site comparison study in Spain found no difference in the occupancy rates of bats roosting in caves with and without fencing or gates installed. Behaviour change (1 study): One controlled, before-and-after study in the USA found that significantly more southeastern myotis bats and gray myotis bats emerged from a cave after a steel gate was replaced with a fence. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1991https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1991Wed, 05 Dec 2018 12:39:50 +0000Collected Evidence: Collected Evidence: Train tourist guides to minimize disturbance and promote bat conservation We found no studies that evaluated the effects of training tourist guides to minimize disturbance and promote bat conservation 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%2F1992https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1992Wed, 05 Dec 2018 12:47:31 +0000Collected Evidence: Collected Evidence: Minimize alterations to caves for tourism We found no studies that evaluated the effects of minimizing alterations to caves for tourism 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%2F1993https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1993Wed, 05 Dec 2018 12:48:48 +0000Collected Evidence: Collected Evidence: Restrict artificial lighting in caves and around cave entrances One study evaluated the effects of restricting artificial lighting in caves on bat populations. The study was in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (1 STUDY) Behaviour change (1 study): One controlled study in the USA found that using low intensity white lights or red lights in caves resulted in fewer bat flights than with full white lighting, but the number of bat movements was similar between all three light treatments. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1994https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1994Wed, 05 Dec 2018 12:50:27 +0000Collected Evidence: Collected Evidence: Minimize noise levels within caves One study evaluated the effects of minimizing noise levels within caves on bat populations. The study was in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (1 STUDY) Behaviour change (1 study): One controlled study in the USA found that experimental cave tours with groups that did not talk resulted in fewer bat flights than when groups did talk, but talking did not have an effect on the number of bat movements. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1995https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1995Wed, 05 Dec 2018 12:52:09 +0000Collected Evidence: Collected Evidence: Introduce guidelines for sustainable cave development and use We found no studies that evaluated the effects of introducing guidelines for sustainable cave development and use 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%2F1996https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1996Wed, 05 Dec 2018 12:54:19 +0000
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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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