Collected Evidence: Collected Evidence: Turn deck lights off during night-time setting of longlines to reduce bycatchA single replicated and controlled study in the South Atlantic found significantly lower bycatch rates when deck lights were turned off during line setting at night.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F284https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F284Tue, 24 Jul 2012 14:11:52 +0100Collected Evidence: Collected Evidence: Use larger hooks to reduce seabird bycatch We captured no intervention-based evidence on the impact of large hooks on seabird bycatch. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested 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%2F286https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F286Tue, 24 Jul 2012 16:26:21 +0100Collected Evidence: Collected Evidence: Use a water cannon when setting longlines to reduce seabird bycatch We found no evidence for the effects on seabird bycatch rates of using water cannon when setting longlines. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested 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 actionCollected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F287https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F287Tue, 24 Jul 2012 16:27:42 +0100Collected Evidence: Collected Evidence: Set longlines at the side of the boat to reduce seabird bycatch We found no evidence for the effects on seabird bycatch rates of setting longlines from the side of the boat. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested 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%2F289https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F289Tue, 24 Jul 2012 16:44:03 +0100Collected Evidence: Collected Evidence: Use bait throwers to reduce seabird bycatchA study from Australia found significantly lower seabird bycatch on longlines set with a bait thrower.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F291https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F291Tue, 24 Jul 2012 16:50:50 +0100Collected Evidence: Collected Evidence: Tow buoys behind longlining boats to reduce seabird bycatch We found no evidence for the effects on seabird bycatch rates of towing buoys behind longlining boats. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested 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%2F292https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F292Tue, 24 Jul 2012 16:54:34 +0100Collected Evidence: Collected Evidence: Dye baits to reduce seabird bycatchA randomised replicated and controlled study in Hawaii found that dying bait blue significantly reduced the number of attacks from albatross on baits being set.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F293https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F293Tue, 24 Jul 2012 16:57:28 +0100Collected Evidence: Collected Evidence: Use high-visibility longlines to reduce seabird bycatch We captured no intervention-based evidence on the impact on seabird bycatch of high-visibility longlines. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested 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%2F294https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F294Tue, 24 Jul 2012 16:58:27 +0100Collected Evidence: Collected Evidence: Use a sonic scarer when setting longlines to reduce seabird bycatchA single study from the South Atlantic found that seabird bycatch rates did not appear to be lower on longlines set with a sonic scarer, and that changes in seabird behaviour due to the scarer were only temporary.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F295https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F295Tue, 24 Jul 2012 16:59:51 +0100Collected Evidence: Collected Evidence: Thaw bait before setting lines to reduce seabird bycatchA single study from Australia found that lines set using thawed baits caught significantly fewer seabirds than controls.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F298https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F298Tue, 24 Jul 2012 17:24:13 +0100Collected Evidence: Collected Evidence: Use acoustic alerts on gillnets to reduce seabird bycatchA repeated, randomised and controlled trial in the USA found that sonic alerts reduced the number of common guillemots Uria aalge but not rhinoceros auklets Cerorhinca monocerata caught in gillnets.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F301https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F301Tue, 24 Jul 2012 18:02:45 +0100Collected Evidence: Collected Evidence: Use high-visibility mesh on gillnets to reduce seabird bycatch A repeated, randomised and controlled trial in the USA found that having gillnets made partially from high-visibility mesh was effective in reducing seabird bycatch. Having a greater percentage (25% vs. 10%) of the net made from high-visibility mesh was more effective, but also reduced catch of the target species.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F303https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F303Tue, 24 Jul 2012 18:10:09 +0100Collected Evidence: Collected Evidence: Reduce gillnet deployment time to reduce seabird bycatch We found no evidence for the effects on seabird bycatch rates of reducing gill net deployment time. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested 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%2F304https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F304Tue, 24 Jul 2012 18:11:14 +0100Collected Evidence: Collected Evidence: Reduce ‘ghost fishing’ by lost/discarded gear We found no evidence for the effects on seabird bycatch rates or populations of reducing ghost fishing. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested 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%2F306https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F306Tue, 24 Jul 2012 18:18:01 +0100Collected Evidence: Collected Evidence: Reduce bycatch by employing seasonal or area closures We found no evidence for the effects on seabird populations or bycatch rates of seasonal or area closures. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested 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%2F307https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F307Tue, 24 Jul 2012 18:19:08 +0100Collected Evidence: Collected Evidence: Fit one or more mesh escape panels/windows and one or more soft, rigid or semi-rigid grids or frames to trawl nets One study examined the effects on subtidal benthic invertebrate populations of fitting one or more mesh escape panels/windows and one or more soft, rigid or semi-rigid grids or frames to trawl nets . The study was in the Gulf of Carpentaria (Australia).   COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Unwanted catch abundance (1 study): One replicated, paired, controlled study in Gulf of Carpentaria found that trawl nets fitted with an escape window and a grid reduced the total weight of small unwanted catch and caught fewer unwanted large sponges, compared to unmodified nets. OTHER (1 STUDY) Commercial catch abundance (1 study): One replicated, paired, controlled study in Carpentaria found that trawl nets fitted with an escape window and a grid reduced the catch of commercially targeted prawns, compared to unmodified nets. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2134https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2134Tue, 22 Oct 2019 10:52:46 +0100Collected Evidence: Collected Evidence: Fit one or more soft, semi-rigid, or rigid grids or frames to trawl nets and use square mesh instead of a diamond mesh at the codend One study examined the effects of fitting one or more soft, semi-rigid, or rigid grids or frames to trawl nets and using a square mesh codend on subtidal benthic invertebrates. The study was in the Gulf of St Vincent (Australia).   COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Unwanted catch abundance (1 study): One replicated, paired, controlled study in Gulf of St Vincent found that trawl nets fitted with a rigid U-shaped grid and a square-oriented mesh codend reduced the catch rates of three dominant groups of unwanted invertebrate catch species, compared to unmodified nets. OTHER (1 STUDY) Commercial catch abundance (1 study): One replicated, paired, controlled study in the Gulf of St Vincent found that trawl nets fitted with a rigid U-shaped grid and a square-oriented mesh codend reduced the catch rates of the commercially targeted western king prawn, due to reduced catch of less valuable smaller-sized prawns, compared to unmodified nets. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2137https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2137Tue, 22 Oct 2019 10:57:05 +0100Collected Evidence: Collected Evidence: Fit one or more mesh escape panels/windows to trawl nets and use a square mesh instead of a diamond mesh codend One study examined the effects of fitting one or more mesh escape panels to trawl nets and using a square mesh instead of a diamond mesh codend on subtidal benthic invertebrate populations. The study was in the English Channel (UK).   COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Unwanted catch abundance (1 study): One replicated, paired, controlled study in the English Channel found that trawl nets fitted with two large square mesh release panels and a square mesh codend caught fewer unwanted catch of non-commercial invertebrates compared to standard trawl nets. OTHER (1 STUDY) Commercial catch abundance (1 study): One replicated, paired, controlled study in the English Channel found that trawl nets fitted with two large square mesh release panels and a square mesh codend caught fewer commercial shellfish, and fewer but more valuable commercially important fish, compared to standard trawl nets. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2138https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2138Tue, 22 Oct 2019 10:59:13 +0100Collected Evidence: Collected Evidence: Modify the design/attachments of a shrimp/prawn W-trawl net One study examined the effects of modifying the design/attachments of a W-trawl net used in shrimp/prawn fisheries on unwanted catch of subtidal benthic invertebrate. The study was in Moreton Bay (Australia).   COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Unwanted catch overall abundance (1 study): One replicated, paired, controlled study in Moreton Bay found that four designs of W-trawl nets used in shrimp/prawn fisheries caught less non-commercial unwanted catch of crustaceans compared to a traditional Florida Flyer trawl net. OTHERS (1 STUDY) Commercial catch abundance (1 study): One replicated, paired, controlled study in Moreton Bay found that four designs of W-trawl nets used in shrimp/prawn fisheries caught lower amounts of the commercially targeted prawn species compared to a traditional Florida Flyer trawl net. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2139https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2139Tue, 22 Oct 2019 11:00:22 +0100Collected Evidence: Collected Evidence: Use a larger mesh size on trammel nets One study examined the effects of using a larger mesh size on trammel nets on subtidal benthic invertebrates. The study was in the North Atlantic Ocean (Portugal).   COMMUNITY RESPONSE (1 STUDY) Unwanted catch community composition (1 study): One replicated, controlled, study in the North Atlantic Ocean found that using larger mesh sizes in the inner and/or outer panels of trammel nets did not affect the community composition of unwanted catch of non-commercial invertebrates (discard). POPULATION RESPONSE (1 STUDY) Unwanted catch abundance (1 study): One replicated, controlled, study in the North Atlantic Ocean found that using larger mesh sizes in the inner and/or outer panels of trammel nets did not reduce the abundance of unwanted catch of non-commercial invertebrates (discard). Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2141https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2141Tue, 22 Oct 2019 11:07:22 +0100Collected Evidence: Collected Evidence: Set unwanted catch quotas One study evaluated the effects of setting unwanted catch quotas on reptile populations. This study was in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Survival (1 study): One study in the USA found that following the re-opening of a swordfish long-line fishery with turtle catch limits in place, loggerhead turtle bycatch reached the annual catch limit in two of three years, and when the limit was reached the fishery was closed for the rest of the year. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3549https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3549Wed, 08 Dec 2021 12:07:09 +0000Collected Evidence: Collected Evidence: Promote knowledge exchange between fishers to improve good practice One study evaluated the effects on reptile populations of promoting knowledge exchange between fishers to improve good practice. This study was in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Survival (1 study): One before-and-after study in the USA found that following the introduction of a tool to help facilitate knowledge exchange and the avoidance of loggerhead turtles, loggerhead turtle bycatch was similar compared to the two years before the tool was introduced. BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Human behaviour change (1 study): One before-and-after study in the USA found that following the introduction of a tool to help facilitate avoidance of loggerhead turtles, fishers did not spend less time fishing in the areas recommended for avoidance by the tool.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3558https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3558Wed, 08 Dec 2021 14:13:04 +0000Collected Evidence: Collected Evidence: Modify number of hooks between floats on longlines One study evaluated the effects of modifying the number of hooks between floats on longlines on reptile populations. This study was in the Atlantic and North Pacific. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Unwanted catch (1 study): One replicated study in the Atlantic and North Pacific found that having fewer hooks between floats did not reduce turtle by-catch in the Pacific but had mixed effects in the Atlantic depending on the species. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3580https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3580Wed, 08 Dec 2021 15:25:39 +0000Collected Evidence: Collected Evidence: Install exclusion devices on fishing gear: Snakes & lizards One study evaluated the effects of installing exclusion devices on fishing gear on snake and lizard populations. This study was in Australia. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Unwanted catch (1 study): One replicated study off the coast of Western Australia found that exclusion grids did not prevent sea snakes from entering trawl nets. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3599https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3599Wed, 08 Dec 2021 16:47:50 +0000Collected Evidence: Collected Evidence: Install escape devices on fishing gear: Sea turtles One study evaluated the effects of installing escape devices on fishing gear on sea turtle populations. This study was in the Gulf of Carpentaria (Australia). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Unwanted catch (1 Study): One randomized, paired, controlled study in the Gulf of Carpentaria found that trawl nets with escape devices caught a similar number of sea turtles compared to unmodified nets. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3601https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3601Wed, 08 Dec 2021 17:09:33 +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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