Conservation Evidence: Evidence Data

Collected Evidence: Collected Evidence: Deploy fishing gear at selected depths to avoid unwanted species Five studies examined the effect of deploying fishing gear at selected depths to avoid unwanted species on marine fish populations. Three studies were in the Atlantic Ocean (Florida, Brazil, Canary Islands), and one study was in each of the Pacific Ocean (Hawaii) and the Tasman Sea (Australia). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (5 STUDIES) Reduction of unwanted catch (5 studies): Four of five replicated studies (three controlled, one paired and controlled) in the Pacific Ocean, Atlantic Ocean and the Tasman Sea found that deploying fishing gear (longlines, handlines and traps) at selected depths, including above the seabed instead of on it, reduced the unwanted catches of five of 17 fish species, three of eight shark/ray species, non-commercially targeted fish species and Harrison’s dogfish, compared to depths usually fished. The other study found that different shark species were hooked at different depths in the water column during bottom-set longlining deployments.Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2683https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2683Mon, 30 Nov 2020 16:26:13 +0000Collected Evidence: Collected Evidence: Deploy fishing gear at selected times (day/night) to avoid unwanted species Two studies examined the effect of deploying fishing gear at selected times on marine fish populations. Both studies were in the South Pacific Ocean (Lake Wooloweyah, Australia). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (2 STUDIES) Reduction of unwanted catch (2 studies): One of two replicated, controlled studies in the South Pacific Ocean found that trawling for prawns during the day reduced the overall catch of unwanted fish by number, but not weight, compared to usual night trawling, and the effect differed by species. The other study found that powered handlining in the day avoided catches of Harrison’s dogfish at shallower, but not deeper seamounts, compared to the night. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2684https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2684Mon, 30 Nov 2020 16:40:44 +0000Collected Evidence: Collected Evidence: Selectively avoid unwanted fish based on temperature distribution We found no studies that evaluated the effects of selectively avoiding fish by their temperature distributions 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%2F2685https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2685Mon, 30 Nov 2020 16:56:00 +0000Collected Evidence: Collected Evidence: Reduce duration of fishing gear deployments Four studies examined the effects of reducing the duration of time that fishing gear is deployed in the water on marine fish populations. Two studies were in the North Sea. One study was in the Atlantic Ocean (USA) and one was in both the Barents Sea and Atlantic Ocean (Norway/USA). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Survival (2 studies): Two replicated, controlled studies in the North Sea found that survival of unwanted plaice and/or sole released after capture in beam or pulse trawls was higher after shorter duration trawl deployments, but that the opposite was true for plaice captured in otter trawls, over tow durations of between one and two hours. BEHAVIOUR (0 STUDIES) OTHER (2 STUDIES) Reduction of unwanted catch (1 study): One of two replicated studies (one paired and controlled) in the Barents Sea/Atlantic Ocean and the Atlantic Ocean found that catch rates of unwanted sharks caught in longline gear decreased with decreasing time the gear was deployed in the water, over durations of up to 10 hours. The other study found that shorter tow durations caught similar amounts of small haddock, but more small cod, than longer durations, in bottom trawls fished for between five minutes and one hour. Improved size-selectivity of fishing gear (1 study): One replicated, paired, controlled study in the Barents Sea/Atlantic Ocean found that varying bottom trawl fishing durations between five minutes and two hours had no effect on the size-selectivity of Atlantic cod, haddock or long rough dab. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2686https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2686Mon, 30 Nov 2020 17:00:02 +0000Collected Evidence: Collected Evidence: Change the towing speed of a trawl net One study examined the effect of changing the towing speed of a trawl net on catch of marine fish. The study was in the North Sea (Norway). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Improved size-selectivity of fishing gear (1 study): One replicated, paired study in the North Sea found that changing the towing speed of a bottom trawl net did not increase the size selectivity of small cod and haddock. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2687https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2687Wed, 02 Dec 2020 10:42:04 +0000Collected Evidence: Collected Evidence: Reduce the hauling speed of a trawl net We found no studies that evaluated the effects of reducing the hauling speed of a trawl net 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%2F2688https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2688Wed, 02 Dec 2020 10:47:28 +0000Collected 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%2Fconservationevidencejournal.com%2Factions%2F3829https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3829Fri, 27 May 2022 10:36:30 +0100