Conservation Evidence: Evidence Data

Collected Evidence: Collected Evidence: Release fish that are carrying eggs or live young We found no studies that evaluated the effects of releasing fish that are carrying eggs or live young 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%2F2733https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2733Tue, 02 Feb 2021 12:04:35 +0000Collected Evidence: Collected Evidence: Release males of species known to guard nests during breeding season We found no studies that evaluated the effects of releasing males that guard nests during the breeding season 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%2F2734https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2734Tue, 02 Feb 2021 12:09:39 +0000Collected Evidence: Collected Evidence: Set a minimum landing size for commercially fished species Five studies examined the effects of setting a minimum landing size for commercially fished species on marine fish populations. One study was a global review and one study was in each of the Tasman Sea (Australia), the Baltic Sea (Northern Europe), the Ionian Sea (Greece) and the Northwest Atlantic Ocean (USA). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Reproductive success (2 studies): One global review reported that one of five swordfish fisheries showed an increase in swordfish recruitment after the setting of recommended minimum landing sizes and catch limits, with recruitment in the other fisheries either highly variable or unable to be assessed. One replicated study in the Ionian Sea reported that, despite established minimum sizes, most fish landed in commercial catches were immature, and thus had never spawned. BEHAVIOUR (0 STUDIES) OTHER (3 STUDIES) Reduction of unwanted catch (3 studies): One of three before-and-after studies (one replicated) in the Atlantic Ocean, Tasman Sea and Baltic Sea found that following an increase in the set minimum landing size and mesh size of gill nets the catches of the youngest southern flounder were reduced. The other two found that increasing the minimum landing size did not reduce the catches of discarded dusky flathead and Atlantic cod3, and discarding of flathead increased in one of three cases. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2735https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2735Tue, 02 Feb 2021 14:28:08 +0000Collected Evidence: Collected Evidence: Set a maximum landing size for commercially fished species We found no studies that evaluated the effects of setting a maximum landing size for commercially fished species 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%2F2736https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2736Tue, 02 Feb 2021 14:40:24 +0000Collected Evidence: Collected Evidence: Specify a size range of capture for commercially fished species We found no studies that evaluated the effects of specifying a size range of commercially retained fish species 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%2F2737https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2737Tue, 02 Feb 2021 14:56:52 +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 +0000