Collected 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: Limit the number of fishing vessels or fishing days in an area We found no studies that evaluated the effects on reptile populations of limiting the number of fishing vessels or fishing days in an area. ‘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%2F3550https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3550Wed, 08 Dec 2021 12:09:23 +0000Collected Evidence: Collected Evidence: Limit the length of fishing gear or density of traps in an area We found no studies that evaluated the effects on reptile populations of limiting the length of fishing gear or density of traps in an area. ‘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%2F3551https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3551Wed, 08 Dec 2021 12:11:09 +0000Collected Evidence: Collected Evidence: Reduce duration of time fishing gear is in the water Two studies evaluated the effects on reptile populations of reducing the duration of time fishing gear is in the water. One study was in the Gulf of Gabès (Tunisia) and one was in the Atlantic and North Pacific. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Survival (1 study): One randomized study in the Gulf of Gabès found that retrieving longlines immediately resulted in fewer loggerhead turtles dying compared to when line retrieval was delayed. BEHAVIOUR (0 STUDIES) OTHER (2 STUDIES) Unwanted catch (2 studies): One randomized study in the Gulf of Gabès and one replicated study in the Atlantic and North Pacific found that the amount of time that longlines were in the water for did not affect the number of loggerhead turtles or leatherback and loggerhead turtles caught. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3552https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3552Wed, 08 Dec 2021 12:18:02 +0000Collected Evidence: Collected Evidence: Use visual deterrents on fishing gear Two studies evaluated the effects of using visual deterrents on fishing gear on reptile populations. One study was off the coast of Mexico and one was in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (1 STUDY) Behaviour change (1 study): One replicated, controlled study in the USA found that shark-shaped and spherical deterrents had mixed effects on a range of captive loggerhead turtle behaviours. OTHER (1 STUDY) Unwanted catch: (1 study): One replicated, controlled study off the coast of Mexico found that gillnets with floating shark shapes attached to them caught fewer green turtles than unmodified nets. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3553https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3553Wed, 08 Dec 2021 12:30:30 +0000Collected Evidence: Collected Evidence: Add lights to fishing gear Five studies evaluated the effects of adding lights to fishing gear on reptile populations. Two studies were in the Baja California peninsula (Mexico) and one was in each of Sechura Bay (Peru), the Atlantic and North Pacific and the Adriatic Sea. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Survival (1 study): One randomized, controlled, paired study in the Adriatic Sea found that no loggerhead turtles were caught and died in in gillnets with UV lights whereas some did in nets without lights. BEHAVIOUR (0 STUDIES) OTHER (5 STUDIES) Unwanted catch (5 studies): Four controlled studies (including three replicated and two paired studies) in the Baja California peninsula, Sechura Bay and the Adriatic Sea found that gillnets with LED lights, light sticks or UV lights caught fewer green turtles and loggerhead turtles than nets without lights. One replicated study in the Atlantic and North Pacific found mixed effects of increasing the number of light sticks on longlines on the chance of catching loggerhead and leatherback turtles. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3554https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3554Wed, 08 Dec 2021 13:59:36 +0000Collected Evidence: Collected Evidence: Retain buoys and lines at the sea floor or riverbed when not hauling We found no studies that evaluated the effects on reptile populations of retaining buoys and lines at the sea floor or riverbed when not hauling. ‘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%2F3555https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3555Wed, 08 Dec 2021 14:08:50 +0000Collected Evidence: Collected Evidence: Retain offal on fishing vessels instead of discarding overboard We found no studies that evaluated the effects on reptile populations of retaining offal on fishing vessels instead of discarding overboard. ‘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%2F3556https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3556Wed, 08 Dec 2021 14:10:15 +0000Collected Evidence: Collected Evidence: Set gillnets perpendicular to the shore We found no studies that evaluated the effects on reptile populations of setting gillnets perpendicular to the shore. ‘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%2F3557https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3557Wed, 08 Dec 2021 14:11:22 +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: Use circle hooks instead of J-hooks Eleven studies evaluated the effects of using circle hooks instead of J-hooks on reptile populations. Five studies were in the Atlantic, three were in the Pacific and one study was in each of the Mediterranean, the Atlantic and North Pacific and the western North Atlantic, Azores, Gulf of Mexico and Ecuador. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (3 STUDIES) Survival (3 studies): Two studies (including one replicated, controlled, paired study) off the coast of Hawaii and in the north-east Atlantic Ocean found that survival of loggerhead and leatherback turtles and leatherback and hard-shell sea turtles caught by circle hooks or J-hooks was similar. One review of studies in five pelagic longline fisheries found that fewer sea turtles died when circle hooks were used compared to J-hooks in four of five fisheries. Condition (3 studies): Two replicated, controlled studies in the Mediterranean Sea and south-western Atlantic Ocean found that fewer immature loggerhead turtles and loggerhead turtles swallowed circle hooks compared to J-hooks. One before-and-after study off the coast of Hawaii found that a lower percentage of loggerhead and leatherback turtles were deeply hooked by circle hooks compared to J-hooks. BEHAVIOUR (0 STUDIES) OTHER (11 STUDIES) Unwanted catch (11 studies): Seven of 10 studies (including six replicated, controlled studies) in the Pacific, Atlantic, Atlantic and North Pacific and Mediterranean and one review of studies in five pelagic longline fisheries found that circle hooks or circle hooks and tuna hooks caught fewer sea turtles than J-hooks, or that non-offset G-style circle hooks caught fewer leatherback and hard-shell sea turtles that offset J-Hooks. One of these studies also found that circle hooks caught slightly larger loggerhead turtles than J-hooks, and one also found that offset Gt-style circle hooks caught a similar number of leatherback and hard-shell sea turtles compared to offset J-hooks. One study found that circle hooks caught a similar number of leatherback, green and olive ridley turtles compared to J-hooks. One study found that fish-baited circle hooks caught fewer loggerhead and leatherback turtles than squid-baited J-hooks. The review found mixed effects of using circle hooks compared to J-hooks on unwanted catch of sea turtles depending on the fishery. The other study found mixed effects of using circle hooks or J-hooks in combination with squid or fish bait on the number of loggerhead and leatherback turtles that were caught. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3559https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3559Wed, 08 Dec 2021 14:21:43 +0000Collected Evidence: Collected Evidence: Introduce legislation to control the use of hazardous substances We found no studies that evaluated the effects on reptile populations of introducing legislation to control the use of hazardous substances. ‘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%2F3560https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3560Wed, 08 Dec 2021 14:46:27 +0000Collected Evidence: Collected Evidence: Use ‘bioremediating’ organisms to remove or neutralize pollutants We found no studies that evaluated the effects on reptile populations of using ‘bioremediating’ organisms to remove or neutralize pollutants. ‘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%2F3561https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3561Wed, 08 Dec 2021 14:47:42 +0000Collected Evidence: Collected Evidence: Add chemicals or minerals to sediment to remove or neutralize pollutants We found no studies that evaluated the effects on reptile populations of adding chemicals or minerals to sediment to remove or neutralize pollutants. ‘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%2F3562https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3562Wed, 08 Dec 2021 14:50:43 +0000Collected Evidence: Collected Evidence: Limit, cease or prohibit dumping of garbage and other solid waste We found no studies that evaluated the effects on reptile populations of limiting, ceasing or prohibiting dumping of garbage and other solid waste. ‘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%2F3563https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3563Wed, 08 Dec 2021 14:51:43 +0000Collected Evidence: Collected Evidence: Remove garbage and other solid waste from terrestrial, aquatic and coastal environments One study evaluated the effects of removing garbage and other solid waste from terrestrial, aquatic and coastal environments on reptile populations. This study was in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Reproductive success (1 study): One controlled, before-and-after study in the USA found that removing beach debris from one section of beach did not increase nesting success in that section. BEHAVIOUR (1 STUDY) Use (1 study): One controlled, before-and-after study in the USA found that after the removal of beach debris from one of three beach sections, a higher percentage of both the total nests laid and failed nesting attempts occurred in that section. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3564https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3564Wed, 08 Dec 2021 14:52:44 +0000Collected Evidence: Collected Evidence: Use biodegradable materials to construct fishing gear to prevent entanglement of reptiles in lost or abandoned gear We found no studies that evaluated the effects on reptile populations of using biodegradable materials to construct fishing gear to prevent entanglement of reptiles in lost or abandoned gear. ‘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%2F3565https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3565Wed, 08 Dec 2021 14:56:52 +0000Collected Evidence: Collected Evidence: Prevent the loss and discard of fishing gear and related debris We found no studies that evaluated the effects on reptile populations of preventing the loss and discard of fishing gear and related debris. ‘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%2F3566https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3566Wed, 08 Dec 2021 14:58:04 +0000Collected Evidence: Collected Evidence: Recover lost or discarded fishing gear We found no studies that evaluated the effects on reptile populations of recovering lost or discarded fishing gear. ‘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%2F3567https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3567Wed, 08 Dec 2021 15:04:44 +0000Collected Evidence: Collected Evidence: Remove derelict fishing gear from reptiles found entangled We found no studies that evaluated the effects on reptile populations of removing derelict fishing gear from reptiles found entangled. ‘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%2F3568https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3568Wed, 08 Dec 2021 15:07:01 +0000Collected Evidence: Collected Evidence: Improve treatment standards of sewage and wastewater We found no studies that evaluated the effects on reptile populations of improving treatment standards of sewage and wastewater. ‘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%2F3569https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3569Wed, 08 Dec 2021 15:08:10 +0000Collected Evidence: Collected Evidence: Create walls or barriers to exclude pollutants We found no studies that evaluated the effects on reptile populations of creating walls or barriers to exclude pollutants. ‘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%2F3570https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3570Wed, 08 Dec 2021 15:12:06 +0000Collected Evidence: Collected Evidence: Use non-offset hooks Two studies evaluated the effects of using non-offset hooks on reptile populations. One study was off the Pacific coast of Costa Rica and one was in the north-east Atlantic. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Survival (1 study): One replicated, controlled, paired study in the north-east Atlantic Ocean found that mortality of leatherback turtles was similar when caught with non-offset hooks or offset hooks. BEHAVIOUR (0 STUDIES) OTHER (2 STUDIES) Unwanted catch (2 studies): One of two replicated, paired studies (including one controlled study) off the Pacific coast of Costa Rica and in the north-east Atlantic found that non-offset circle hooks caught a similar number of olive ridley and green turtles compared to offset circle hooks in a shallow-set longline fishery. The other study found that non-offset G-style circle hooks caught fewer leatherback and hard-shell turtles compared to offset Gt-style circle hooks or offset J-hooks in a longline swordfish fishery. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3571https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3571Wed, 08 Dec 2021 15:13:12 +0000Collected Evidence: Collected Evidence: Cease or prohibit discharge of waste effluents overboard from vessels We found no studies that evaluated the effects on reptile populations of ceasing or prohibiting discharge of waste effluents overboard from vessels. ‘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%2F3572https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3572Wed, 08 Dec 2021 15:13:22 +0000Collected Evidence: Collected Evidence: Establish emergency plans for oil spills We found no studies that evaluated the effects on reptile populations of establishing emergency plans for oil spills. ‘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%2F3573https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3573Wed, 08 Dec 2021 15:14:32 +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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