Collected Evidence: Collected Evidence: Modify aquaculture gear We found no studies that evaluated the effects of modifying aquaculture gear 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%2F2742https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2742Tue, 02 Feb 2021 15:42:55 +0000Collected Evidence: Collected Evidence: Modify anti-predator nets around aquaculture systems We found no studies that evaluated the effects of modifying anti-predator nets around aquaculture systems 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%2F2743https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2743Tue, 02 Feb 2021 16:22:41 +0000Collected Evidence: Collected Evidence: Minimize food waste at aquaculture systems We found no studies that evaluated the effects of minimizing food waste at aquaculture systems 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%2F2744https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2744Tue, 02 Feb 2021 16:41:13 +0000Collected Evidence: Collected Evidence: Modify design of underwater turbines We found no studies that evaluated the effects of modifying the design of underwater turbines 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%2F2747https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2747Tue, 02 Feb 2021 16:46:52 +0000Collected Evidence: Collected Evidence: Reduce capacity of cooling water intake structures We found no studies that evaluated the effects of reducing capacity of cooling water intake structures 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%2F2752https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2752Tue, 02 Feb 2021 16:54:58 +0000Collected Evidence: Collected Evidence: Provide training to vessel operators on mammal behaviour and appropriate avoidance techniques We found no studies that evaluated the effects of providing training to vessel operators on mammal behaviour and appropriate avoidance techniques. ‘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%2F2759https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2759Tue, 02 Feb 2021 17:03:34 +0000Collected Evidence: Collected Evidence: Provide educational materials at marinas and ports to encourage vessel operators to carry out safe practices around mammals (e.g. signs, leaflets) We found no studies that evaluated the effects of providing educational materials at marinas and ports to encourage vessel operators to carry out safe practices 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%2Fwww.conservationevidence.com%2Factions%2F2760https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2760Tue, 02 Feb 2021 17:04:29 +0000Collected Evidence: Collected Evidence: Modify vessels to reduce risk of physical injury to mammals We found no studies that evaluated the effects of modifying vessels to reduce risk of physical injury to 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%2Fwww.conservationevidence.com%2Factions%2F2762https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2762Tue, 02 Feb 2021 17:06:48 +0000Collected Evidence: Collected Evidence: Prohibit or restrict hunting of marine and freshwater mammal species Five studies evaluated the effects of prohibiting hunting of marine mammal species. One study was in each of the Kattegat and Skagerrak seas (Denmark and Sweden), the North Atlantic Ocean, North Pacific Ocean and the Southern Hemisphere, the South Pacific Ocean (Australia), the North Atlantic Ocean (Greenland) and the Southern Ocean (Australia). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (5 STUDIES) Abundance (5 studies): Four of five studies (including three before-and-after studies) in the Kattegat and Skagerrak Seas, the South Pacific Ocean, the North Atlantic Ocean and the Southern Ocean found that after hunting was prohibited, the abundance of harbour seals and humpback whales increased over 7–30 years. The other study found that numbers of mature male sperm whales did not differ significantly before or 31 years after hunting was prohibited. One review in the North Atlantic Ocean, North Pacific Ocean and the Southern Hemisphere found significant increase rates for 10 of 12 baleen whale populations during 7–21 years after legislation to prohibit hunting was introduced. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2780https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2780Thu, 04 Feb 2021 16:09:52 +0000Collected Evidence: Collected Evidence: Reduce duration of time fishing gear is in the water We found no studies that evaluated the effects of reducing the duration of time fishing gear is in the water 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%2F2796https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2796Thu, 04 Feb 2021 16:38:40 +0000Collected Evidence: Collected Evidence: Play predator calls to deter mammals from fishing gear One study evaluated the effects of playing predator calls to deter mammals from fishing gear. The study was in the South Atlantic Ocean (Africa). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Human-wildlife conflict (1 study): One study in the South Atlantic Ocean found that playing killer whale vocalisations did not deter Cape fur seals from feeding on fish catches in a purse-seine net or trawl net. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2817https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2817Fri, 05 Feb 2021 15:08:39 +0000Collected Evidence: Collected Evidence: Modify fishing pots and traps to exclude mammals Six studies evaluated the effects on marine mammals of modifying fishing pots and traps to exclude mammals. Two studies were in the North Sea (UK, Sweden) and one study was in each of the Indian River Lagoon (USA), the Gulf of Finland (Finland), the Bothnian Sea (Finland), the Indian Ocean (Australia) and the Baltic Sea (Sweden). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (6 STUDIES) Reduction in entanglements/unwanted catch (2 studies): Two controlled studies (including one replicated study) in the Indian Ocean, and the Baltic Sea and North Sea found that installing steel rods on lobster pots or metal frames on fishing pots reduced the number of Australian sea lion pups or grey seals and harbour seals that entered or became trapped in pots. Human wildlife conflict (4 studies): Two controlled studies (including one replicated study) in the Bothnian Sea and the North Sea found that installing wire grids or steel bars on fishing trap-nets or bag-nets, along with strengthened netting or other modifications to prevent seal access, reduced damage to salmon catches by seals. One controlled study in the Indian River Lagoon found that one of two methods of securing crab pot doors with a bungee cord reduced the number of common bottlenose dolphin interactions. One controlled study in the Gulf of Finland found that installing wire grids on trap-nets, along with strengthened netting, resulted in higher catches of undamaged salmon but not whitefish, likely due to reduced seal predation. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2822https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2822Fri, 05 Feb 2021 15:35:30 +0000Collected Evidence: Collected Evidence: Provide training and tools for safe release of mammals captured by fisheries We found no studies that evaluated the effects of providing training and tools for the safe release of mammals captured by fisheries 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%2F2830https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2830Fri, 05 Feb 2021 16:03:59 +0000Collected Evidence: Collected Evidence: Promote fish and seafood certification (e.g. ecolabels) to reduce consumer demand for fisheries that threaten mammals We found no studies that evaluated the effects of promoting fish and seafood certification (e.g. ecolabels) 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%2F2836https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2836Fri, 05 Feb 2021 16:09:36 +0000Collected Evidence: Collected Evidence: Maintain water level and flow along regulated rivers We found no studies that evaluated the effects of maintaining water level and flow along regulated 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%2Fwww.conservationevidence.com%2Factions%2F2850https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2850Fri, 05 Feb 2021 16:39:24 +0000Collected Evidence: Collected Evidence: Physically remove invasive or problematic species We found no studies that evaluated the effects of physically removing invasive or other problematic species 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%2F2851https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2851Mon, 08 Feb 2021 10:58:53 +0000Collected Evidence: Collected Evidence: Reduce pesticide, herbicide or fertilizer use We found no studies that evaluated the effects of reducing pesticide, herbicide or fertilizer use 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%2F2879https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2879Mon, 08 Feb 2021 11:44:13 +0000Collected Evidence: Collected Evidence: Recover lost or discarded fishing gear We found no studies that evaluated the effects of recovering lost or discarded fishing gear 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%2F2886https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2886Mon, 08 Feb 2021 11:49:11 +0000Collected Evidence: Collected Evidence: Offer incentives to fishers for recovering, reusing or recycling fishing gear We found no studies that evaluated the effects of offering incentives to fishers for recovering, reusing or recycling fishing gear 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%2F2887https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2887Mon, 08 Feb 2021 11:49:52 +0000Collected Evidence: Collected Evidence: Reduce hammer energy during pile driving We found no studies that evaluated the effects of reducing hammer energy during pile driving 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%2F2900https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2900Mon, 08 Feb 2021 16:10:51 +0000Collected Evidence: Collected Evidence: Limit, cease or prohibit the use of sonars We found no studies that evaluated the effects of limiting, ceasing or prohibiting the use of sonars 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%2F2902https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2902Mon, 08 Feb 2021 16:13:57 +0000Collected Evidence: Collected Evidence: Limit, cease or prohibit the use of underwater explosives We found no studies that evaluated the effects of limiting, ceasing or prohibiting the use of underwater explosives 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%2F2903https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2903Mon, 08 Feb 2021 16:14:39 +0000Collected Evidence: Collected Evidence: Modify vessels to reduce noise disturbance We found no studies that evaluated the effects of modifying vessels to reduce noise disturbance 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%2F2904https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2904Mon, 08 Feb 2021 16:15:34 +0000Collected Evidence: Collected Evidence: Manage water levels and flow in rivers to maintain deep pools and connectivity We found no studies that evaluated the effects of managing water levels and flow in rivers to maintain deep pools and connectivity 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%2F2914https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2914Mon, 08 Feb 2021 16:24:21 +0000Collected Evidence: Collected Evidence: Place orphaned or abandoned marine and freshwater mammal young with foster parents We found no studies that evaluated the effects of placing orphaned or abandoned marine and freshwater mammal young with foster parents. ‘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%2F2928https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2928Tue, 09 Feb 2021 11:07:43 +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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