Collected 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%2Fwww.conservationevidence.com%2Factions%2F2790https%3A%2F%2Fwww.conservationevidence.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%2Fwww.conservationevidence.com%2Factions%2F2792https%3A%2F%2Fwww.conservationevidence.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%2Fwww.conservationevidence.com%2Factions%2F2793https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2793Thu, 04 Feb 2021 16:33:47 +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 the length of fishing gear in an area We found no studies that evaluated the effects of limiting the length of fishing gear 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%2F2795https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2795Thu, 04 Feb 2021 16:37:57 +0000Collected Evidence: Collected Evidence: Limit size of trawl net openings We found no studies that evaluated the effects of limiting the size of trawl net openings 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%2F2804https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2804Thu, 04 Feb 2021 17:14:32 +0000Collected Evidence: Collected Evidence: Increase visual detectability of fishing gear for mammals Two studies evaluated the effects on marine mammals of increasing the visual detectability of fishing gear for mammals. One study was in the Gulf of St. Lawrence (Canada) and one was in Cape Cod Bay (USA). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (2 STUDIES) Behaviour change (2 studies): One study in the Gulf of St. Lawrence found that minke whales approached white ropes more slowly and changed their bearing more when approaching black ropes compared to ropes of other colours. One study in Cape Cod Bay found that simulated ropes painted red or orange were detected by North Atlantic right whales at greater distances than green but not black ropes, and more whales collided with green ropes than the other three rope colours. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2805https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2805Thu, 04 Feb 2021 17:16:45 +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%2Fwww.conservationevidence.com%2Factions%2F2806https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2806Thu, 04 Feb 2021 17:20:11 +0000Collected Evidence: Collected Evidence: Install exclusion and/or escape devices for mammals on fishing nets Seven studies evaluated the effects on marine mammals of installing exclusion and/or escape devices on fishing nets. Four studies were in the Indian Ocean (Australia, Tasmania) and/or Tasman Sea (Tasmania) and three studies were in the South Atlantic Ocean (South Georgia). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Survival (2 studies): One study in the Indian Ocean found that less than one third of common bottlenose dolphins exited escape hatches on trawl nets alive. One replicated study in the Tasman Sea and Indian Ocean found that fewer fur seals died in exclusion devices with large escape openings than in those with small openings. BEHAVIOUR (0 STUDIES) OTHER (5 STUDIES) Reduction in entanglements/unwanted catch (5 studies): Three studies (including two controlled studies) in the South Atlantic Ocean and Indian Ocean found that installing exclusion and/or escape devices on trawl nets reduced the number of trapped or entangled Antarctic fur seals and common bottlenose dolphins. One before-and-after study in the Indian Ocean found that installing exclusion and escape devices on trawl nets reduced common bottlenose dolphin entanglements for three of four fishing vessels. One study in the South Atlantic Ocean found that modifying an exclusion and escape device by enlarging and relocating the escape panel resulted in fewer Antarctic fur seal entanglements. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2823https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2823Fri, 05 Feb 2021 15:39:04 +0000Collected Evidence: Collected Evidence: Install barriers at wild fisheries One study evaluated the effects on freshwater mammals of installing a barrier at a wild fishery. The study was in the Puntledge River (Canada). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Human-wildlife conflict (1 study): One randomized, controlled study in the Puntledge River found that installing a ‘cork line’ barrier did not deter harbour seals from feeding on salmon released from a hatchery. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2824https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2824Fri, 05 Feb 2021 15:52:33 +0000Collected Evidence: Collected Evidence: Establish handling and release protocols for mammals captured by fisheries One study evaluated the effects on marine mammals of establishing handling and release protocols for mammals captured by wild fisheries. 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 a code of conduct for releasing dolphins trapped in nets, along with avoiding dolphins during fishing, resulted in lower mortality of short-beaked common dolphins. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2829https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2829Fri, 05 Feb 2021 16:02:48 +0000Collected Evidence: Collected Evidence: Introduce legislation to prohibit or restrict the use of fishing gear types or methods that are harmful to mammals We found no studies that evaluated the effects of introducing legislation to prohibit or restrict the use of fishing gear types 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%2Fwww.conservationevidence.com%2Factions%2F2831https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2831Fri, 05 Feb 2021 16:05:04 +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%2Fwww.conservationevidence.com%2Factions%2F2832https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2832Fri, 05 Feb 2021 16:05:50 +0000Collected Evidence: Collected Evidence: Involve fishers in designing and trialling new fishing gear types to encourage uptake of gear that reduces unwanted catch of mammals We found no studies that evaluated the effects of involving fishers in designing and trialling new fishing gear types to encourage uptake of gear that reduces unwanted catch of 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%2Fwww.conservationevidence.com%2Factions%2F2833https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2833Fri, 05 Feb 2021 16:06:36 +0000Collected Evidence: Collected Evidence: Introduce fishing gear exchange programmes to encourage fishers to use gear that reduces unwanted catch of mammals We found no studies that evaluated the effects of introducing fishing gear exchange programmes to encourage fishers to use gear that reduces unwanted catch of 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%2Fwww.conservationevidence.com%2Factions%2F2834https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2834Fri, 05 Feb 2021 16:07:26 +0000Collected Evidence: Collected Evidence: Finance low interest loans to convert to fishing gear that reduces unwanted catch of mammals We found no studies that evaluated the effects of financing low interest loans to convert to fishing gear that reduces unwanted catch of 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%2Fwww.conservationevidence.com%2Factions%2F2835https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2835Fri, 05 Feb 2021 16:08:28 +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%2Fwww.conservationevidence.com%2Factions%2F2837https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2837Fri, 05 Feb 2021 16:10:27 +0000
What Works 2021 cover

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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