Collected Evidence: Collected Evidence: Use a different method to sort or bring catch onboard We found no studies that evaluated the effects of using different methods to sort or bring catches onboard vessels 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%2F2689https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2689Wed, 02 Dec 2020 14:45:13 +0000Collected Evidence: Collected Evidence: Reduce the duration of exposure to air of captured fish before release Three studies examined the effect of reducing the duration of exposure of fish to air on marine fish populations. One study was in each of the Bay of Biscay (Spain), Gulf of Alaska (Canada) and Coral Sea (Australia).  COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Survival (1 study): One replicated study in the Bay of Biscay found that reducing air exposure before release did not increase the survival of small-spotted catshark caught during commercial trawling. Condition (1 study): One replicated study in the Gulf of Alaska found that shorter durations of air exposure before release improved the physical condition and reduced the amount of injury to discarded chum salmon caught in purse seine nets.  BEHAVIOUR (1 STUDY) Behaviour change (1 study): One study in the Coral Sea found that minimal exposure to air and handling resulted in improved overall behaviour after release (activity and ability to return to reef) of reef fish, compared to fish exposed to air and handling for longer duration. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2690https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2690Wed, 02 Dec 2020 14:47:25 +0000Collected Evidence: Collected Evidence: Release protected or species of concern alive after capture Six studies examined the effects of releasing protected or species of concern alive after capture on marine fish populations. Two studies were in the Atlantic Ocean (USA and Canada), and one was in each of the Coral Sea (Australia), Tasman Sea (New Zealand), Cantabrian Sea (Spain) and the Pacific Ocean (USA).  COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (6 STUDIES) Survival (6 studies): Four of six replicated studies in the Atlantic Ocean, Tasman Sea, Cantabrian Sea and the Pacific Ocean found that the majority (76–92%) of unwanted (discarded or protected) small-spotted catshark, thorny skate, pearl perch and Atlantic wolffish, but less than half of smooth skate, survived for at least 1 h–5 days after capture and/or release, and survival was reduced by hooking/capture depth injuries and longer tow durations. One study found that nearly all yelloweye rockfish survived for four days after capture and release, but canary rockfish survival decreased with increasing capture depth. The other study found that all spinetail devilrays brailed aboard from purse seine nets survived but not those brought aboard entangled in the net. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2691https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2691Wed, 02 Dec 2020 14:55:19 +0000Collected Evidence: Collected Evidence: Establish handling and release protocols in non-recreational fisheries Two studies examined the effects of establishing handling and release protocols in non-recreational fisheries on marine fish populations. One study was in the Atlantic Ocean (West Africa) and one was in the South Pacific Ocean (Australia).  COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Survival (1 study): One study in the Atlantic Ocean reported that tracked whale sharks released from purse seines using an enhanced protocol survived for at least 21 days, and post-release movements appeared normal. BEHAVIOUR (2 STUDIES) Behaviour change (2 studies): One study in the Pacific Ocean found that after release protocols (minimal handling and air exposure), reef fish returned more quickly to a reef or the seabed after release, compared to higher stress handling and longer air exposure. One study in the Atlantic Ocean reported that the post-release movements of tracked whale sharks released from purse seines using an enhanced protocol appeared normal. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2692https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2692Wed, 02 Dec 2020 15:51:06 +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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