Collected Evidence: Collected Evidence: Cease or prohibit shellfish dredging One study examined the effects of ceasing or prohibiting shellfish dredging on marine fish populations. The study was in the North Sea (Denmark). COMMUNITY RESPONSE (1 STUDY) Richness/diversity (1 study): One before-and-after, site comparison study in the North Sea reported that 10 years after mussel dredging ceased in an area closed to all towed fishing gears there was no change in species richness of bottom-dwelling fish compared to before and to open areas. POPULATION RESPONSE (1 STUDY) Abundance (1 study): One before-and-after, site comparison study in the North Sea, reported that ceasing mussel dredging in an area closed to all towed gears had no effect on the abundance of bottom-dwelling fish after 10 years, and compared to open areas. BEHAVIOUR (0 STUDIESCollected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2668https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2668Thu, 19 Nov 2020 15:42:05 +0000Collected Evidence: Collected Evidence: Cease or prohibit mobile midwater (pelagic) fishing gears One study examined the effects of ceasing or prohibiting fishing with towed (mobile) midwater fishing gears on marine fish populations. The study was in the Norwegian Sea (Norway). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Condition (1 study): One replicated, before-and-after study in the Norwegian Sea found that in the five years after drift netting was prohibited in an area, the weights of young salmon returning to rivers were higher than before, and weights of older salmon were similar or lower. Abundance (1 study): One replicated, before-and-after study in the Norwegian Sea found that in the five years after the use of drift nets was prohibited, there were more young salmon returning to rivers than before, and similar numbers of older multi-returning salmon. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2669https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2669Thu, 19 Nov 2020 16:06:33 +0000Collected Evidence: Collected Evidence: Cease or prohibit all non-towed (static) fishing gear One study examined the effects of ceasing or prohibiting all non-towed (static) fishing gears on marine fish populations. The study was in the Coral Sea (Australia).   COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): One replicated, site comparison study in the Coral Sea found that in areas closed to non-towed fishing gears overall shark abundance was higher when sampled with longlines but not gillnets compared to areas where commercial gillnets were permitted. Condition (1 study): One replicated, site comparison study in the Coral Sea found that in areas closed to non-towed fishing gears shark length was greater for two of five species/groups, similar for two and dependent on sampling gear for one species, compared to areas where commercial gillnets were permitted. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2670https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2670Thu, 19 Nov 2020 16:10:49 +0000Collected Evidence: Collected Evidence: Cease or prohibit line fishing One study examined the effects of ceasing or prohibiting line fishing in an area on marine fish populations. The study was in the Indian Ocean (South Africa). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY)  Abundance (1 study): One site comparison study in the Indian Ocean found that prohibiting offshore line fishing and all other boat-based fishing in a zone of a marine protected area resulted in higher abundances of four of four fish species over-exploited by line fishing, compared to two zones where boat-based line and spear fishing was permitted. Condition (1 study): One site comparison study in the Indian Ocean found that in a zone of a marine protected area closed to offshore line fishing and all other boat-based fishing for two to seven years, four of four fish species over-exploited by line fishing were larger, compared to two zones where boat-based line and spear fishing was permitted. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2671https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2671Thu, 19 Nov 2020 16:41:12 +0000Collected Evidence: Collected Evidence: Cease or prohibit customary fishing (indigenous fishing for cultural and community needs) One study examined the effects of ceasing or prohibiting customary fishing in an area, on marine fish populations. The study was in the Bismark Sea (Papua New Guinea). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): One site comparison study in the Bismark Sea found a higher abundance of only one of seven fish species in an area closed to customary fishing for eight years, compared to an area open to customary fishing. BEHAVIOUR (1 STUDY) Behaviour change (1 study): One site comparison study in the Bismark Sea found that in an area closed to customary fishing for eight years, six of seven fish species had a lower flight response distance compared to an area open to customary fishing, making them more vulnerable to capture with spear guns. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2675https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2675Fri, 27 Nov 2020 15:46:26 +0000Collected Evidence: Collected Evidence: Establish territorial fishing use rights One study examined the effects of establishing territorial fishing use rights in an area on marine fish populations. The study was in the Pacific Ocean (Tonga). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Reduction of fishing effort (1 study): One study in the Pacific Ocean found that there was no decrease in overall fishing effort in an area with new territorial fishing use rights and a co-management system, in the five years after implementation. Commercial catch abundance (1 study): One study in the Pacific Ocean found that in an area with new territorial fishing use rights and a co-management system, total fish catch rates did not increase and catch rates of three of six individual fish groups decreased in the first five years. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2677https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2677Fri, 27 Nov 2020 15:51:57 +0000Collected Evidence: Collected Evidence: Allow only small-scale, traditional (artisanal) fishing One study examined the effects of allowing only small-scale traditional (artisanal) fishing in an area on marine fish populations. The study was in the Adriatic Sea (Italy). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Commercial catch abundance (1 study): One site comparison study in the Adriatic Sea found that a marine protected area zone allowing only artisanal fishing activity for three years had higher overall commercial catch rates of five of seven species compared to unprotected areas openly fished. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2678https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2678Fri, 27 Nov 2020 16:09:39 +0000Collected Evidence: Collected Evidence: Promote knowledge exchange between fishers to improve good practice We found no studies that evaluated the effects of promoting knowledge exchange between fishers to improve good practice 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%2F2814https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2814Fri, 05 Feb 2021 10:10:50 +0000Collected Evidence: Collected Evidence: Limit beam trawl width We found no studies that evaluated the effects of limiting beam trawl width 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%2F3805https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3805Thu, 26 May 2022 14:36:31 +0100Collected Evidence: Collected Evidence: Limit dredge width or number of dredges per vessel We found no studies that evaluated the effects of limiting dredge width or number of dredges 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%2F3806https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3806Thu, 26 May 2022 14:40:55 +0100Collected 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: Set catch shares by area We found no studies that evaluated the effects of setting catch shares by 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%2F3813https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3813Fri, 27 May 2022 08:29:31 +0100Collected Evidence: Collected Evidence: Introduce fishing permit/licence or charter schemes We found no studies that evaluated the effects of introducing fishing permit/licence or charter schemes 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%2F3816https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3816Fri, 27 May 2022 08:40:24 +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 +0100Collected Evidence: Collected Evidence: Purchase fishing permits from fishers to limit vessel or fisher numbers We found no studies that evaluated the effects of purchasing fishing permits from fishers 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%2F3818https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3818Fri, 27 May 2022 08:43:16 +0100Collected Evidence: Collected Evidence: Purchase fishing vessels from fishers to limit vessel numbers We found no studies that evaluated the effects of purchasing fishing vessels from fishers to limit vessel 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%2F3819https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3819Fri, 27 May 2022 08:45:56 +0100Collected Evidence: Collected Evidence: Eliminate fisheries subsidies that encourage overfishing We found no studies that evaluated the effects of eliminating fisheries subsidies that encourage overfishing 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%2F3820https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3820Fri, 27 May 2022 08:47:44 +0100Collected Evidence: Collected Evidence: Implement vessel decommissioning schemes We found no studies that evaluated the effects of implementing vessel decommissioning schemes 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%2F3821https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3821Fri, 27 May 2022 08:48:57 +0100Collected Evidence: Collected Evidence: Prohibit the catching and/or landing of specific fish species We found no studies that evaluated the effects of prohibiting catching and/or landing of specific species 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%2F3822https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3822Fri, 27 May 2022 08:51:56 +0100Collected Evidence: Collected Evidence: Implement multi-species management strategies We found no studies that evaluated the effects of implementing multi-species management strategies 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%2F3824https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3824Fri, 27 May 2022 09:02:14 +0100Collected Evidence: Collected Evidence: Employ adaptive management methods to achieve long-term goals We found no studies that evaluated the effects of employing adaptive management methods to achieve long-term goals 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%2F3827https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3827Fri, 27 May 2022 09:41:07 +0100Collected Evidence: Collected Evidence: Introduce gear exchange programs We found no studies that evaluated the effects of introducing gear exchange programmes 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%2F3828https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3828Fri, 27 May 2022 09:42:22 +0100Collected Evidence: Collected Evidence: Introduce a pause when hauling dredge gear We found no studies that evaluated the effects of introducing a pause when hauling dredge gear 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%2F3829https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3829Fri, 27 May 2022 10:36:30 +0100Collected Evidence: Collected Evidence: Enforce gear and vessel restrictions (e.g. cap engine power, ban gears) We found no studies that evaluated the effects of enforcing gear and vessel restrictions (e.g. cap engine power, ban gears) 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%2F3830https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3830Mon, 30 May 2022 08:47:04 +0100
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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