Collected Evidence: Collected Evidence: Divert shipping routes We found no studies that evaluated the effects of diverting shipping routes 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%2Fconservationevidence.com%2Factions%2F2754https%3A%2F%2Fconservationevidence.com%2Factions%2F2754Tue, 02 Feb 2021 16:57:34 +0000Collected Evidence: Collected Evidence: Develop and implement regulations for operating vessels around mammals We found no studies that evaluated the effects of developing and implementing regulations for operating vessels around mammals. ‘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%2Fconservationevidence.com%2Factions%2F2758https%3A%2F%2Fconservationevidence.com%2Factions%2F2758Tue, 02 Feb 2021 17:02:30 +0000Collected Evidence: Collected Evidence: Enforce legislation to prevent the trafficking and trade of marine and freshwater mammal products We found no studies that evaluated the effects of enforcing legislation to prevent the trafficking and trade of marine and freshwater mammal products. ‘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%2Fconservationevidence.com%2Factions%2F2781https%3A%2F%2Fconservationevidence.com%2Factions%2F2781Thu, 04 Feb 2021 16:16:18 +0000Collected Evidence: Collected Evidence: Educate local communities and fishers on mammal protection laws to reduce killing of marine and freshwater mammals We found no studies that evaluated the effects of educating local communities and fishers on mammal protection laws to reduce killing of marine and freshwater mammals. ‘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%2Fconservationevidence.com%2Factions%2F2788https%3A%2F%2Fconservationevidence.com%2Factions%2F2788Thu, 04 Feb 2021 16:26:07 +0000Collected Evidence: Collected Evidence: Establish ‘move-on rules’ for fishing vessels if mammals are encountered One study evaluated the effects on marine mammals of establishing move-on rules for fishing vessels if mammals are encountered. The study was in the Great Australian Bight (Australia). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Survival (1 study): One before-and-after study in the Great Australian Bight found that introducing measures to delay or relocate fishing if dolphins were encountered, along with releasing trapped dolphins, resulted in fewer short-beaked common dolphins being encircled and killed. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fconservationevidence.com%2Factions%2F2790https%3A%2F%2Fconservationevidence.com%2Factions%2F2790Thu, 04 Feb 2021 16:29:13 +0000Collected Evidence: Collected Evidence: Deploy fishing gear at times when mammals are less active We found no studies that evaluated the effects of deploying fishing gear at times when mammals are less active 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%2Fconservationevidence.com%2Factions%2F2792https%3A%2F%2Fconservationevidence.com%2Factions%2F2792Thu, 04 Feb 2021 16:31:14 +0000Collected Evidence: Collected Evidence: Deploy fishing gear at different depths One study evaluated the effects on marine mammals of deploying fishing gear at different depths. The study was in the Arafura Sea (Australia). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Reduction in entanglements/unwanted catch (1 study): One controlled study in the Arafura Sea found that fishing nets deployed 4.5 m below the water surface had fewer entanglements of dolphins than surface nets. Collected Evidencehttps%3A%2F%2Fconservationevidence.com%2Factions%2F2793https%3A%2F%2Fconservationevidence.com%2Factions%2F2793Thu, 04 Feb 2021 16:33:47 +0000Collected Evidence: Collected Evidence: Attach acoustically reflective objects to fishing gear Two studies evaluated the effects on marine mammals of attaching acoustically reflective objects to fishing gear. One study was in the Timor Sea and Arafura Sea (Australia) and one was in the Gulf of Alaska (USA). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (2 STUDIES) Reduction in entanglements/unwanted catch (1 study): One controlled study in the Timor Sea and Arafura Sea found that attaching metallic bead chains to fishing nets did not reduce the number of dolphin entanglements. Human-wildlife conflict (1 study): One controlled study in the Gulf of Alaska found that attaching acrylic beads next to fishing hooks did not reduce predation on fish catches by sperm whales. Collected Evidencehttps%3A%2F%2Fconservationevidence.com%2Factions%2F2806https%3A%2F%2Fconservationevidence.com%2Factions%2F2806Thu, 04 Feb 2021 17:20:11 +0000Collected Evidence: Collected Evidence: Enforce legislation to control illegal fishing using gear or methods that are harmful to mammals We found no studies that evaluated the effects of enforcing legislation to control illegal fishing using gear or methods that are harmful to mammals 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%2Fconservationevidence.com%2Factions%2F2832https%3A%2F%2Fconservationevidence.com%2Factions%2F2832Fri, 05 Feb 2021 16:05:50 +0000Collected Evidence: Collected Evidence: Educate the public to reduce consumer demand for fisheries that threaten mammals We found no studies that evaluated the effects of educating the public to reduce consumer demand for fisheries that threaten mammals 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%2Fconservationevidence.com%2Factions%2F2837https%3A%2F%2Fconservationevidence.com%2Factions%2F2837Fri, 05 Feb 2021 16:10:27 +0000Collected Evidence: Collected Evidence: Create designated areas or access points for recreational activities We found no studies that evaluated the effects of creating designated areas or access points for recreational activities 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%2Fconservationevidence.com%2Factions%2F2842https%3A%2F%2Fconservationevidence.com%2Factions%2F2842Fri, 05 Feb 2021 16:22:19 +0000Collected Evidence: Collected Evidence: Carry out surveillance for diseases We found no studies that evaluated the effects of carrying out surveillance for diseases 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%2Fconservationevidence.com%2Factions%2F2857https%3A%2F%2Fconservationevidence.com%2Factions%2F2857Mon, 08 Feb 2021 11:14:33 +0000Collected Evidence: Collected Evidence: Add chemicals or minerals to sediment to remove or neutralize pollutants We found no studies that evaluated the effects of adding chemicals or minerals to sediment to remove or neutralize pollutants 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%2Fconservationevidence.com%2Factions%2F2864https%3A%2F%2Fconservationevidence.com%2Factions%2F2864Mon, 08 Feb 2021 11:25:33 +0000Collected Evidence: Collected Evidence: Cease or prohibit the disposal of mining waste (tailings) at sea or in rivers We found no studies that evaluated the effects of ceasing or prohibiting the disposal of mining waste (tailings) at sea or in rivers 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%2Fconservationevidence.com%2Factions%2F2873https%3A%2F%2Fconservationevidence.com%2Factions%2F2873Mon, 08 Feb 2021 11:38:16 +0000Collected Evidence: Collected Evidence: Cease or prohibit the disposal of drill cuttings at sea or in rivers We found no studies that evaluated the effects of ceasing or prohibiting the disposal of drill cuttings at sea or in rivers 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%2Fconservationevidence.com%2Factions%2F2874https%3A%2F%2Fconservationevidence.com%2Factions%2F2874Mon, 08 Feb 2021 11:40:05 +0000Collected Evidence: Collected Evidence: Create artificial wetlands to reduce the amount of pollutants reaching rivers and the sea We found no studies that evaluated the effects of creating artificial wetlands to reduce effluent reaching rivers and the sea 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%2Fconservationevidence.com%2Factions%2F2881https%3A%2F%2Fconservationevidence.com%2Factions%2F2881Mon, 08 Feb 2021 11:45:37 +0000Collected Evidence: Collected Evidence: Equip ports with dedicated fishing gear disposal facilities We found no studies that evaluated the effects of equipping ports with dedicated fishing gear disposal facilities 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%2Fconservationevidence.com%2Factions%2F2888https%3A%2F%2Fconservationevidence.com%2Factions%2F2888Mon, 08 Feb 2021 11:50:38 +0000Collected Evidence: Collected Evidence: Delay or cease operations if marine and freshwater mammals are detected within a specified zone We found no studies that evaluated the effects of delaying or ceasing operations if marine and freshwater mammals are detected within a specified zone 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%2Fconservationevidence.com%2Factions%2F2898https%3A%2F%2Fconservationevidence.com%2Factions%2F2898Mon, 08 Feb 2021 16:09:16 +0000Collected Evidence: Collected Evidence: Enforce existing legislation for habitat protection We found no studies that evaluated the effects of enforcing existing legislation for habitat protection 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%2Fconservationevidence.com%2Factions%2F2916https%3A%2F%2Fconservationevidence.com%2Factions%2F2916Mon, 08 Feb 2021 16:30:18 +0000Collected Evidence: Collected Evidence: Cease or prohibit activities that cause disturbance in sensitive areas for marine and freshwater mammals Two studies evaluated the effects of prohibiting activities that cause disturbance in sensitive areas for marine mammals. One study was in the Kattegat Sea (Denmark) and one in the Indian Ocean (Australia). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): One before-and-after study in the Kattegat sea found that harbour porpoise activity increased at a stony reef after fishing was prohibited and the reef was restored with boulders. BEHAVIOUR (1 STUDY) Behaviour change (1 study): One site comparison study in the Indian Ocean found that a beach where human access was fully prohibited had fewer Australian sea lions showing aggression or retreating compared to a beach where access was partly prohibited. Collected Evidencehttps%3A%2F%2Fconservationevidence.com%2Factions%2F2917https%3A%2F%2Fconservationevidence.com%2Factions%2F2917Mon, 08 Feb 2021 16:33:04 +0000Collected Evidence: Collected Evidence: Cease or prohibit activities that cause disturbance during sensitive periods for marine and freshwater mammals We found no studies that evaluated the effects of ceasing or prohibiting activities that cause disturbance during sensitive periods for marine and freshwater mammals. ‘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%2Fconservationevidence.com%2Factions%2F2918https%3A%2F%2Fconservationevidence.com%2Factions%2F2918Mon, 08 Feb 2021 16:34:09 +0000Collected Evidence: Collected Evidence: Create artificial habitat for marine and freshwater mammals We found no studies that evaluated the effects of creating artificial habitat for marine and freshwater mammals. ‘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%2Fconservationevidence.com%2Factions%2F2921https%3A%2F%2Fconservationevidence.com%2Factions%2F2921Mon, 08 Feb 2021 16:36:58 +0000Collected Evidence: Collected Evidence: Breed marine and freshwater mammals in captivity Six studies evaluated the effects of breeding marine and freshwater mammals in captivity. Three studies were in the USA, one study was also in China, Indonesia and Venezuela, and one study was in each of South Africa, Hong Kong and China. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (6 STUDIES) Reproductive success (2 studies): One study in Hong Kong found that four of six female Indo-Pacific dolphins successfully conceived during a controlled captive breeding programme and gave birth to a total of nine calves. One study in China found that wild-caught Yangtze finless porpoises successfully reproduced in semi-captive conditions. Survival (4 studies): Two studies in South Africa and the USA found that a captive-born common bottlenose dolphin, and a captive-born and hand-reared common bottlenose dolphin, survived in captivity for at least two and a half years and four years respectively. One review in the USA found that 80% of common bottlenose dolphins born in captivity over two decades survived, and survival increased with improved husbandry techniques. One review in the USA, China, Indonesia and Venezuela found that most captive-born Amazon river dolphins, narrow-ridged finless porpoises and Irrawaddy dolphins did not survive in captivity. Condition (1 study): One study in China found that a population of Yangtze finless porpoises breeding in semi-captive conditions had low genetic diversity. BEHAVIOUR (1 STUDY) Behaviour change (1 study): One study in the USA found that a captive-born and hand-reared common bottlenose dolphin displayed normal behaviour for the species and joined a dolphin social group in captivity. Collected Evidencehttps%3A%2F%2Fconservationevidence.com%2Factions%2F2932https%3A%2F%2Fconservationevidence.com%2Factions%2F2932Tue, 09 Feb 2021 11:30:25 +0000Collected Evidence: Collected Evidence: Engage policymakers to make policy changes beneficial to marine and freshwater mammals One study evaluated the effects of engaging policymakers to make changes beneficial to marine and freshwater mammals. The study was in the Catazajá wetlands (Mexico). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (1 STUDY) Change in human behaviour (1 study): One study in the Catazajá wetlands reported that engaging policymakers resulted in the designation of a protected area for West Indian manatees. Collected Evidencehttps%3A%2F%2Fconservationevidence.com%2Factions%2F2934https%3A%2F%2Fconservationevidence.com%2Factions%2F2934Tue, 09 Feb 2021 11:38:17 +0000Collected Evidence: Collected Evidence: Educate the public to improve behaviour towards marine and freshwater mammals Three studies evaluated the effects of educating the public to improve behaviour towards marine and freshwater mammals. One study was in each of the North Atlantic Ocean (USA), the Sundarbans mangroves (Bangladesh) and the South Pacific Ocean (Peru). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (3 STUDIES) Change in human behaviour (3 studies): Three before-and-after studies in the North Atlantic Ocean, the Sundarbans mangroves and the South Pacific Ocean found that after educational whale-watching tours or an educational exhibition, participants were more willing to change their behaviour to support marine conservation, to donate money to marine conservation, or to cut their fishing nets to save entangled dolphins. Collected Evidencehttps%3A%2F%2Fconservationevidence.com%2Factions%2F2935https%3A%2F%2Fconservationevidence.com%2Factions%2F2935Tue, 09 Feb 2021 11:41:45 +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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