Collected Evidence: Collected Evidence: Limit time that researchers/tourists are allowed to spend with habituated animals One controlled study in Indonesia found that reintroduced Sumatran orangutans that spent limited time with caretakers acted more similar to wild orangutans than orangutans that spend more time with caretakers, alongside other interventions. One before-and-after study in Rwanda, Uganda and the Democratic Republic of Congo found that numbers of mountain gorillas increased by 168% over 41 years while being visited by researchers and visitors during a restricted amount of time, alongside other interventions. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1539https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1539Thu, 19 Oct 2017 15:12:10 +0100Collected Evidence: Collected Evidence: Limit the thickness of drill cuttings We found no studies that evaluated the effects of limiting the thickness of drill cuttings on subtidal benthic invertebrate 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%2F2065https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2065Mon, 21 Oct 2019 13:47:49 +0100Collected Evidence: Collected Evidence: Limit, cease or prohibit recreational boating We found no studies that evaluated the effects of limiting, ceasing or prohibiting recreational fishing and/or harvesting on subtidal benthic invertebrate 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%2F2088https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2088Mon, 21 Oct 2019 14:59:55 +0100Collected Evidence: Collected Evidence: Limit, cease or prohibit anchoring from ships/boats/vessels We found no studies that evaluated the effects of setting limits, ceasing or prohibitinganchroing from ships/boats/vessels on subtidal benthic invertebrate 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%2F2089https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2089Mon, 21 Oct 2019 15:19:19 +0100Collected Evidence: Collected Evidence: Limit the number of fishing vessels We found no studies that evaluated the effects of limiting the number of fishing vessels on subtidal benthic invertebrate 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%2F2109https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2109Tue, 22 Oct 2019 09:36:55 +0100Collected Evidence: Collected Evidence: Limit the number of traps per fishing vessels We found no studies that evaluated the effects of limiting the number of traps per fishing vessels on subtidal benthic invertebrate 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%2F2110https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2110Tue, 22 Oct 2019 09:37:40 +0100Collected Evidence: Collected Evidence: Limit, cease or prohibit access for recreational purposes We found no studies that evaluated the effects of limiting, ceasing or prohibiting access for recreational purposes on subtidal benthic invertebrate 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%2F2152https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2152Tue, 22 Oct 2019 12:02:44 +0100Collected Evidence: Collected Evidence: Limit, cease or prohibit ballast water exchange in specific areas We found no studies that evaluated the effects of limiting, ceasing or prohibiting ballast water exchange in specific areas on subtidal benthic invertebrate 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%2F2164https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2164Tue, 22 Oct 2019 12:14:28 +0100Collected Evidence: Collected Evidence: Limit, cease or prohibit discharge of solid waste overboard from vessels We found no studies that evaluated the effects of limiting, ceasing or prohibiting discharge of solid waste overboard from vessels on subtidal benthic invertebrate 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%2F2202https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2202Tue, 22 Oct 2019 13:13:36 +0100Collected Evidence: Collected Evidence: Limit, cease or prohibit industrial and urban lighting at night We found no studies that evaluated the effects of limiting, ceasing or prohibiting industrial and urban lighting at night on subtidal benthic invertebrate 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%2F2208https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2208Tue, 22 Oct 2019 13:20:07 +0100Collected Evidence: Collected Evidence: Limit vessel traffic in shallow rivers We found no studies that evaluated the effects of limiting vessel traffic in shallow rivers on freshwater mammal 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%2F2764https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2764Tue, 02 Feb 2021 17:08:45 +0000Collected Evidence: Collected Evidence: Limit the number of fishing vessels or fishing days in an area We found no studies that evaluated the effects of limiting the number of fishing vessels or fishing days in an area on marine and freshwater mammal 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%2F2794https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2794Thu, 04 Feb 2021 16:36:53 +0000Collected Evidence: Collected Evidence: Limit, cease or prohibit feeding of marine and freshwater mammals by tourists One study evaluated the effects of setting limits on feeding of marine mammals by tourists. The study was in Shark Bay (Australia). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Survival (1 study): One controlled, before-and-after study in Shark Bay found that after setting limits on feeding of bottlenose dolphins by tourists, the survival of calves born to females being fed increased and was similar to calves of non-fed mothers. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2845https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2845Fri, 05 Feb 2021 16:31:57 +0000Collected Evidence: Collected Evidence: Limit, cease or prohibit ballast water exchange in specific areas We found no studies that evaluated the effects of limiting, ceasing or prohibiting ballast water exchange in specific areas on marine and freshwater mammal 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%2F2853https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2853Mon, 08 Feb 2021 11:00:40 +0000Collected Evidence: Collected Evidence: Limit, cease or prohibit dumping of untreated sewage We found no studies that evaluated the effects of limiting, ceasing or prohibiting dumping of untreated sewage on marine and freshwater mammal 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%2F2865https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2865Mon, 08 Feb 2021 11:26:21 +0000Collected Evidence: Collected Evidence: Limit, cease or prohibit dumping of sewage sludge We found no studies that evaluated the effects of limiting, ceasing or prohibiting dumping of sewage sludge on marine and freshwater mammal 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%2F2866https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2866Mon, 08 Feb 2021 11:26:58 +0000Collected Evidence: Collected Evidence: Limit, cease or prohibit discharge of solid waste overboard from vessels We found no studies that evaluated the effects of limiting, ceasing or prohibiting discharge of solid waste overboard from vessels on marine and freshwater mammal 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%2F2893https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2893Mon, 08 Feb 2021 11:57:41 +0000Collected Evidence: Collected Evidence: Limit, cease or prohibit discharge of waste effluents overboard from vessels We found no studies that evaluated the effects of limiting, ceasing or prohibiting discharge of waste effluents overboard from vessels, on marine and freshwater mammal 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%2F2907https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2907Mon, 08 Feb 2021 16:18:11 +0000Collected Evidence: Collected Evidence: Limit vessel numbers We found no studies that evaluated the effects of limiting vessel numbers on reptile 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%2F3529https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3529Tue, 07 Dec 2021 15:37:06 +0000Collected Evidence: Collected Evidence: Limit vessel speeds Three studies evaluated the effects of limiting vessel speeds on reptiles. One study was in each of Australia, Costa Rica and the USA. COMMUNITY RESPONSE (0 STUDIES)   POPULATION RESPONSE (2 STUDIES) Survival (2 studies): One replicated, site comparison study in Costa Rica found that in waterways with enforced speed limits, fewer spectacled caiman were found dead with boat-related injuries compared to waterways with no speed limits. One replicated study in the USA found that vessels travelling at lower speeds caused fewer catastrophic injuries to artificial loggerhead turtle shells, though vessels with jet motors caused no catastrophic injuries at any speed tested. Condition (1 study): One replicated, site comparison study in Costa Rica found that in waterways with enforced speed limits, fewer spectacled caiman were found with boat-related injuries compared to waterways with no speed limits. BEHAVIOUR (1 STUDY) Behaviour change (1 study): One replicated study in Australia found that green turtles were more likely to flee from vessels travelling at lower speeds. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3531https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3531Tue, 07 Dec 2021 15:40:57 +0000Collected Evidence: Collected Evidence: Limit the number of fishing vessels or fishing days in an area We found no studies that evaluated the effects on reptile populations of limiting the number of fishing vessels or fishing days in an area. ‘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%2F3550https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3550Wed, 08 Dec 2021 12:09:23 +0000Collected Evidence: Collected Evidence: Limit, cease or prohibit dumping of garbage and other solid waste We found no studies that evaluated the effects on reptile populations of limiting, ceasing or prohibiting dumping of garbage and other solid waste. ‘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%2F3563https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3563Wed, 08 Dec 2021 14:51:43 +0000Collected Evidence: Collected Evidence: Limit the number of traps or pots per vessel We found no studies that evaluated the effects of limiting the number of traps or pots per vessel on marine fish 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%2F3807https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3807Thu, 26 May 2022 14:42:42 +0100Collected Evidence: Collected Evidence: Limit the number or length of static fishing nets in an area We found no studies that evaluated the effects of limiting the number or length of static fishing nets in an area on marine fish 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%2F3808https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3808Thu, 26 May 2022 14:45:45 +0100Collected Evidence: Collected Evidence: Limit the number of fishing permits/licences to limit vessel or fisher numbers We found no studies that evaluated the effects of limiting the number of fishing licences or permits to limit vessel or fisher numbers on marine fish 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%2F3817https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3817Fri, 27 May 2022 08:41:37 +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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