Collected Evidence: Collected Evidence: Use human observers onboard fishing vessels to monitor catches and discards We found no studies that evaluated the effects of using human observers onboard fishing vessels to monitor catches and discards 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%2Fconservationevidencejournal.com%2Factions%2F2740https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2740Tue, 02 Feb 2021 15:15:25 +0000Collected Evidence: Collected Evidence: Use citizen surveillance to report illegal fishing We found no studies that evaluated the effects of using citizen surveillance to report illegal fishing 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%2Fconservationevidencejournal.com%2Factions%2F2741https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2741Tue, 02 Feb 2021 15:37:26 +0000Collected Evidence: Collected Evidence: Enforce port controls We found no studies that evaluated the effects of enforcing port controls 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%2Fconservationevidencejournal.com%2Factions%2F2766https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2766Wed, 03 Feb 2021 10:03:11 +0000Collected Evidence: Collected Evidence: Use onboard CCTV for monitoring catches and discards We found no studies that evaluated the effects of using onboard CCTV monitoring 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%2Fconservationevidencejournal.com%2Factions%2F2767https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2767Wed, 03 Feb 2021 10:05:44 +0000Collected Evidence: Collected Evidence: Use flags to signal the legal nationality of a fishing vessel We found no studies that evaluated the effects of using a flag to identify the legal nationality of a fishing 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%2Fconservationevidencejournal.com%2Factions%2F2768https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2768Wed, 03 Feb 2021 10:10:41 +0000Collected Evidence: Collected Evidence: Eliminate flags of convenience We found no studies that evaluated the effects of eliminating flags of convenience 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%2Fconservationevidencejournal.com%2Factions%2F2769https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2769Wed, 03 Feb 2021 10:27:16 +0000Collected Evidence: Collected Evidence: Establish open and transparent reporting of fishing effort data We found no studies that evaluated the effects of establishing open and transparent fishing effort data 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%2Fconservationevidencejournal.com%2Factions%2F2770https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2770Wed, 03 Feb 2021 10:37:50 +0000Collected Evidence: Collected Evidence: Use methods to trace the source of catch We found no studies that evaluated the effects of using methods to trace the sources of catches 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%2Fconservationevidencejournal.com%2Factions%2F2771https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2771Wed, 03 Feb 2021 11:18:06 +0000Collected Evidence: Collected Evidence: Issue high fines and penalties for non-compliance with fisheries regulations We found no studies that evaluated the effects of issuing high fines and penalties for non-compliance with fisheries regulations 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%2Fconservationevidencejournal.com%2Factions%2F2772https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2772Wed, 03 Feb 2021 11:19:38 +0000Collected Evidence: Collected Evidence: License fish buyers We found no studies that evaluated the effects of licensing fish buyers 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%2Fconservationevidencejournal.com%2Factions%2F2773https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2773Wed, 03 Feb 2021 11:25:34 +0000Collected Evidence: Collected Evidence: Include fishers in management groups for marine protected areas We found no studies that evaluated the effects of including fishers in management fora for marine protected areas 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%2Fconservationevidencejournal.com%2Factions%2F2809https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2809Fri, 05 Feb 2021 10:00:36 +0000Collected Evidence: Collected Evidence: Involve fishers in designing and trialling new gear types to encourage uptake of more selective fishing gear We found no studies that evaluated the effects of involving fishers in designing and trialling new gear types 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%2Fconservationevidencejournal.com%2Factions%2F2810https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2810Fri, 05 Feb 2021 10:02:04 +0000Collected Evidence: Collected Evidence: Introduce economic incentives to encourage sustainable fishing We found no studies that evaluated the effects of introducing economic incentives to encourage sustainable fishing 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%2Fconservationevidencejournal.com%2Factions%2F2811https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2811Fri, 05 Feb 2021 10:03:40 +0000Collected Evidence: Collected Evidence: Involve stakeholders in allocation of harvest rights We found no studies that evaluated the effects of involving stakeholders in the allocation of harvest rights 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%2Fconservationevidencejournal.com%2Factions%2F2812https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2812Fri, 05 Feb 2021 10:07:06 +0000Collected Evidence: Collected Evidence: Engage stakeholders/fishers in scientific research and data collection We found no studies that evaluated the effects of engaging fishers in scientific data collection 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%2Fconservationevidencejournal.com%2Factions%2F2813https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2813Fri, 05 Feb 2021 10:08:31 +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%2Fconservationevidencejournal.com%2Factions%2F2814https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2814Fri, 05 Feb 2021 10:10:50 +0000Collected Evidence: Collected Evidence: Involve fishers and stakeholders in co-management Three studies examined the effect of involving fishers and stakeholders in co-management on marine fish populations. One study was in each of the Indian Ocean, the South China Sea (Vietnam) and the Pacific Ocean (Tonga).  COMMUNITY RESPONSE (1 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): One before-and-after study the Indian Ocean found that involving fishers and stakeholders in co-management increased overall fish abundance, but abundance varied between species groups, nine years after implementation compared to before. BEHAVIOUR (0 STUDIES) OTHER (2 STUDIES) Reduction of fishing effort (1 study): One before-and-after study in the Pacific Ocean found that in the five years after implementation of a new co-management system there was no decrease in overall fishing effort in the managed area. Commercial catch abundance (1 study): One before-and-after study in the Pacific Ocean found no increase in total fish catch rates and a decrease in catch rates of half of the six species groups individually inside an area with a new co-management system after five years. Improved compliance/reduction of illegal fishing activity (1 study): One before-and-after study in the South China Sea reported that after co-management was established in an area there was a decrease in illegal fishing using destructive fishing gears. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2910https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2910Mon, 08 Feb 2021 16:20:11 +0000Collected Evidence: Collected Evidence: Protect spawning fish from capture Four studies examined the effects of protecting spawning fish on marine fish populations. Two studies were in the North Atlantic Ocean (Canada, UK) and one study was in each of the Philippine Sea (Palau) and the Tasman Sea (Australia).  COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): One before-and-after, site comparison study in the Atlantic Ocean found no increase in the biomass of the spawning stock of Atlantic cod in the nine years following implementation of a seasonal fishery closure to protect spawning cod, compared to fished areas. Survival (1 study): One before-and-after, site comparison study in the Atlantic Ocean found no change in Atlantic cod survival in the nine years after a seasonal fishery closure to protect spawning cod was implemented, compared to fished areas. Condition (1 study): One before-and-after, site comparison study in the Atlantic Ocean found no change in the length composition of Atlantic cod in the nine years following a seasonal fishery closure to protect spawning cod, compared to fished areas. BEHAVIOUR (2 STUDIES) Use (2 studies): One site comparison study and one study in the Northeast Atlantic Ocean and Tasman Sea reported that spawning and/or nursery areas closed seasonally or permanently to fishing were used by tagged adult Atlantic cod for nearly a third of time during spawning, and by school sharks less than one year old for up to 80% of time, but by school sharks between one and two years old for 18% of time, compared to areas outside. OTHER (2 STUDIES) Commercial catch abundance (2 studies): One before-and-after, site comparison study in the Atlantic Ocean found no change over nine years in commercial catches of Atlantic cod following a seasonal fishery closure to protect spawning cod compared to fished areas. One replicated, controlled study in the Philippine Sea found that during seasonal closure of a grouper fishery to protect spawning individuals, the commercial catch numbers of other fish groups (herbivores) increased, indicating they were being targeted more by spear fishers compared to the open season. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2938https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2938Thu, 11 Feb 2021 16:13:52 +0000Collected Evidence: Collected Evidence: Limit the number of fishing days One study examined the effects of limiting the number of fishing days on marine fish populations. The study was in the Mediterranean Sea (Italy). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): One before-and-after study in the Mediterranean Sea reported that in the 10 years following a decrease in overall number of days fished by a bottom trawl fleet, there was a higher biomass of thornback and brown rays. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3804https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3804Thu, 26 May 2022 14:24:22 +0100Collected 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%2Fconservationevidencejournal.com%2Factions%2F3805https%3A%2F%2Fconservationevidencejournal.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%2Fconservationevidencejournal.com%2Factions%2F3806https%3A%2F%2Fconservationevidencejournal.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%2Fconservationevidencejournal.com%2Factions%2F3807https%3A%2F%2Fconservationevidencejournal.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%2Fconservationevidencejournal.com%2Factions%2F3808https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3808Thu, 26 May 2022 14:45:45 +0100Collected Evidence: Collected Evidence: Limit fishing activity by vessel size and/or engine power One study examined the effects of limiting fishing activity by vessel size and/or engine power on marine fish populations. The study was in the North Sea (Northern Europe).   COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): One before-and-after study in the North Sea found that after vessels with a higher engine power were excluded from an area for half of each year there was a higher abundance of commercially targeted fish, but no difference in the overall abundance of non-commercially targeted fish over five years. In addition, for all fish, abundance was higher for two of eight size-groups. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3809https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3809Thu, 26 May 2022 14:53:03 +0100Collected Evidence: Collected Evidence: Prohibit certain gear types Two studies examined the effects of prohibiting certain gear types on marine fish populations. One study was in the Indian Ocean (Kenya) and one was in the Kattegat (Sweden/Denmark).   COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): One replicated, site comparison study in the Indian Ocean found that in an area where all but one gear type was prohibited there was a higher fish density compared to areas where just one gear type was prohibited and to unrestricted areas. BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Reduction of unwanted catch (1 study): One replicated, before-and-after study in the Kattegat found that a combination of areas in which non-selective gear types were prohibited and long-term fishery closures reduced unwanted catch of cod compared to before. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3810https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3810Thu, 26 May 2022 14:57:28 +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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