Conservation Evidence: Evidence Data

Collected Evidence: Collected Evidence: Cease or prohibit all commercial fishing Eight studies examined the effects of ceasing or prohibiting all commercial fishing in an area on marine fish populations. Two studies were in the Tasman Sea (Australia), and one was in each of the Indian Ocean (Australia), the Mediterranean Sea (Spain), the Greenland Sea (Iceland), the Gulf of Mexico (USA), the South China Sea (China) and the South Atlantic Ocean (South Africa). COMMUNITY RESPONSE (3 STUDIES) Community composition (3 studies): Two before-and-after studies (one site comparison) in the Tasman Sea and South China Sea found that the fish assemblage/species composition was different before and after prohibiting all commercial fishing, in an estuary after two years, and in the nearby wider region surrounding two marine reserves five years after their creation. One site comparison study in the South Atlantic Ocean found no change in species composition between a reserve closed to all commercial fishing for 40 years and unprotected fished areas. Richness/diversity (2 studies): One site comparison study in the South Atlantic Ocean found no difference in overall fish diversity between a protected area closed to all commercial fishing for 40 years compared to unprotected fished areas. One before-and-after study in the South China Sea found that fish species richness decreased in the wider region five years after all commercial fishing was banned in two marine reserves. POPULATION RESPONSE (7 STUDIES) Abundance (7 studies): Two of four site comparison studies (one replicated, one before-and-after) in the Mediterranean Sea, Indian Ocean, south Atlantic Ocean and the Gulf of Mexico found that in protected areas prohibiting all commercial fishing for five years and 40 years there were higher abundances of three of 12 commercially targeted and non-targeted fish species/groups and one of four commercially targeted fish species, compared to unprotected fished areas. One study found mixed effects on fish densities 30–40 years after banning all commercial fishing, varying with level of commercial exploitation, and higher abundances of five of five commercially exploited species. The other study found there was no increase in white seabream and gilthead bream biomass 2–13 years after closure compared to an unprotected fished area, but it was lower than a no-take area protected for over nine years. One before-and-after, site comparison study in the Tasman Sea found that most fish species in an estuary in a marine reserve had a lower abundance two years after it was closed to all commercial fishing than before, as did one of two reference sites in unprotected adjacent estuaries. One before-and-after study in the South China Sea found that in the five years after the creation of two marine reserves with limits on commercial fishing activity, overall fish density in the nearby wider region increased. One replicated, site comparison study in the Tasman Sea found that in areas of a marine reserve closed to commercial trapping, fish abundance varied over 10 years and was higher for some groups than others compared to reserve sites open to trapping. Condition (1 study): One replicated, site comparison study in the Indian Ocean found that in marine reserve areas banning all commercial fishing for five years, overall fish size was bigger compared to fished areas. BEHAVIOUR (1 STUDY) Use (1 study): One replicated, controlled study in the Greenland Sea found that areas closed to commercial fishing (trawling) had higher recaptures of tagged smaller immature cod than adult cod over time compared to trawled areas, indicating they were more likely to have an increased protection from fishing. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2667https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2667Thu, 19 Nov 2020 11:03:46 +0000Collected Evidence: Collected Evidence: Cease or prohibit all types of fishing in a marine protected area Seventy-nine studies examined the effects of ceasing or prohibiting all types of fishing in a marine protected area on fish populations. Fifteen studies were in the Indian Ocean (Kenya, Tanzania, South Africa, Mozambique, Madagascar, multiple African countries, Australia). Twelve studies were in the Mediterranean Sea (Spain, France, Italy). Ten studies were in the Pacific Ocean (New Zealand, USA, Hawaii, New Caledonia, Costa Rica, Tonga, Vanuatu, Solomon Islands). Seven studies were in each of the Coral Sea (Australia, Vanuatu), the Tasman Sea (New Zealand, Australia) and the Atlantic Ocean (Brazil, USA, Puerto Rico, Argentina, South Africa, UK, Canary Islands, Portugal, Turks and Caicos Islands). Four studies were in the Philippine Sea (Philippines). Three studies were in the Caribbean Sea (Belize, Puerto Rico). One study was in each of the Gulf of Mexico (USA), the Java Sea (Indonesia), the Pacific and Indian Oceans (multiple countries), the Sulu Sea (Malaysia) and the North Sea (Norway). Six studies were reviews of marine reserves (New Zealand, Latin America/Caribbean, regions unspecified and across the world). COMMUNITY RESPONSE (26 STUDIES) Community composition (7 studies): Seven site comparison studies (two replicated, and one before-and-after) in the Mediterranean Sea, Indian Ocean, Philippine Sea and the Atlantic Ocean found that protected areas where all fishing had been prohibited for between three and 16 years, had a different fish community composition, compared to fished areas. Richness/diversity (22 studies): Fourteen of 20 site comparison studies (eight replicated, one replicated and paired, and one before-and-after) in the Indian Ocean, Mediterranean Sea, Philippine Sea, Tasman Sea, Atlantic Ocean, Caribbean Sea, Coral Sea and the Pacific Ocean, found that marine protected areas that had prohibited all fishing for between one to more than 25 years, had higher fish species/richness compared to fished areas. Six studies found similar fish species/richness between one and 20 years after all fishing was banned in protected areas, compared to fished areas. One systematic review in the Atlantic and Pacific Oceans found no difference in species richness between unfished protected areas and fished areas. One replicated, site comparison study in the Indian Ocean found that the effects of prohibiting all fishing on fish species richness/diversity after 15 years varied with the sampling method used. POPULATION RESPONSE (66 STUDIES) Abundance (64 studies): Thirty of 54 site comparison studies (18 replicated, eight replicated and paired, two before-and-after, one paired and before-and-after, and one replicated and before-and-after) in the Indian Ocean, Atlantic Ocean, Mediterranean Sea, Pacific Ocean, Tasman Sea, Coral Sea, Philippine Sea, Caribbean Sea, Gulf of Mexico, and the Sulu Sea, found that marine protected areas that had been prohibiting all fishing for up to 25 years or more, had higher abundances (density and/or biomass) of all fish (total fish biomass, total fish density), fishery targeted fish species, non-fishery targeted fish species and all or most of the individual fish species/groups monitored, except fish densities (all or most) and non-fishery targeted species, compared to unprotected fished areas and/or partly-fished protected areas. The studies also found that in some cases where the total fish biomass or densities were higher in no-fished areas, the effect varied between individual groups of fish based on species family and/or position in the food chain, commercial target and non-target species, fish sizes, depth and habitat types. Eight studies found that inside protected areas prohibiting all fishing there were similar abundances of all fish, and all or most of the individual fish species/groups monitored, compared to fished areas between one and 20 years after implementation. The other sixteen studies found that the effect of prohibiting fishing in protected areas for three to 20 years on fish abundance varied between fish species or groups and on their fished status (fishery target or non-target) and/or position in the food chain. One also found that the effect varied with size or age of the protected areas. Five of six reviews (three systematic) across the world, in the Pacific and/or Atlantic Oceans and in unreported regions found that non-fished marine reserves with one to 27 years of protection had higher abundances of all fish, all fish and invertebrates combined and blue cod compared to fished areas, but there were differences between species/groups and fishing intensity outside reserves. The other review found that fish abundance varied between species in no-take marine reserves between one and 25 years old, and was affected by food chain position, level of exploitation and duration of protection. One replicated study in the Pacific Ocean found a long-term decline in the abundance/presence of eight of 12 shark and ray species inside an established (>15 years) no-fishing protected area, however enforcement was poor. One before-and after, site comparison study in the Pacific Ocean, found no differences in overall fish abundance between a marine reserve closed permanently to fishing for five years and a closed area that was harvested for two years during the same period. One site comparison study in the Coral Sea found that in a no-take zone of an area protected for at least 10 years, fish abundance of four of six fish groups were similar to no-entry and fished zones, but two had lower abundance than the no-entry zone. One replicated, paired, site comparison study in the Tasman Sea found that in a non-fished marine park zone abundance of commercially targeted fish was higher than partly fished zones but lower than unprotected areas after four to eight years. Reproductive success (1 study): One site comparison study in the Mediterranean Sea found more eggs of four commercially targeted fish species inside a non-fished marine reserve enforced for three years than in fished areas outside the reserve. Survival (1 study): One site comparison study in the Atlantic Ocean found that prohibiting all fishing in a marine protected area for three years resulted in similar survival of red hind grouper, compared to fished areas. Condition (20 studies): Two global review studies (one systematic) and two systematic reviews in the Pacific Ocean and the Atlantic and Pacific Oceans found that prohibiting all fishing in marine protected areas for one to 27 years resulted in larger fish overall and larger blue cod compared to fished areas, but there were differences between individual fish families or species. Eight of 11 site comparison studies (four replicated, one before-and-after, one paired, and one replicated and paired) in the Tasman Sea, Pacific Ocean, Indian Ocean, Mediterranean Sea, Atlantic Ocean, Java Sea and the Philippine Sea, found that non-fished protected areas had larger fish overall and larger individuals of all or most of the fish species/groups monitored, compared to fished areas, after one to 22 years. The other three studies found similar fish sizes of all or all but one species, compared to fished areas one to 16 years after all fishing was prohibited. Three site comparison studies (one replicated) in the Coral Sea, Caribbean Sea and the Atlantic Ocean found that fish size in protected areas that had not been fished for six to more than 20 years, varied between fish species or food chain groups. One site comparison study in the Atlantic Ocean found that red hind grouper were larger, but had similar growth, in an area protected from fishing for three years compared to fished areas. One site comparison study in the Atlantic Ocean found that young lemon sharks in areas protected from fishing for 20 years had similar growth rates, but lower condition, than sharks in unprotected fished areas. BEHAVIOUR (2 STUDIES) Behaviour change (2 studies): One replicated, site comparison study in the Pacific and Indian Oceans found that surgeonfish and parrotfish inside established protected areas where fishing was prohibited, showed a similar avoidance response to fishing gears as in fished areas, and this increased with increasing fishing intensity outside the protected areas. One replicated, site comparison study in the Indian Ocean found that in non-fished areas protected for one and 24 years, fish grazing rates were higher compared to fished areas. OTHER (15 STUDIES) Use (7 studies): Four of six site comparison studies in the Pacific Ocean, Atlantic Ocean and the Tasman Sea found that marine protected areas where all fishing had been prohibited for at least five to 15 years, were used for a large proportion of time by shark and ray species and commercially important reef fish species, compared to fished areas, thus were provided protection from fishing. Two other studies found that time spent inside areas closed to all fishing for 20 years and over 30 years, varied between species and with size for three shark species and with size for giant trevally. One replicated study in the Indian Ocean found that most individuals of five fish species remained inside a marine reserve zone closed to fishing over a nine-year period. Catch abundance (2 studies): One of two site comparison studies in the Mediterranean Sea and Pacific Ocean found that commercial fish catch rates in small-scale traditional fisheries were highest closest to a marine reserve closed to all fishing for 22 years, and decreased with increasing distance from the reserve. The other study found that there was no increase in fish catch rates in commercially landed catch in the five years after a no-fishing zone was implemented in a co-managed protected area. Stock biomass (1 study): One replicated, site comparison study in the Indian Ocean found that the stock biomass (the harvested portion of the population) of reef fish species was highest in enforced protected areas closed to all fishing, compared to various other area management regimes. Fishing mortality (2 studies): Two site comparison studies in the North Sea and Pacific Ocean found that prohibiting fishing in protected areas resulted in reduced commercial fishing mortality of corkwing wrasse tagged inside non-fished marine reserves compared to fished areas, and that the overall fishing mortality of grey reef sharks tagged inside protected areas was low. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2682https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2682Sat, 28 Nov 2020 14:35:06 +0000Collected Evidence: Collected Evidence: Fit a size-sorting escape grid (rigid or flexible) to a prawn/shrimp trawl net Thirty studies examined the effects of fitting size-sorting escape grids to prawn/shrimp trawl nets on marine fish populations. Five studies were in the North Sea (Scotland/Norway, Belgium/Netherlands, UK, Scotland), four were in the Coral Sea (Australia) and two were in each of the Gulf of Carpentaria (Australia), the Indian Ocean (Australia, Mozambique), the North Atlantic Ocean (Portugal, USA), the Pacific Ocean (Chile, USA), the Skagerrak and Kattegat (northern Europe) and the South Atlantic Ocean (Brazil). One study was in each of the Tasman Sea (Australia), the Greenland Sea (Svalbard), the Bay of Biscay (France), the Gulf of Maine (USA), the Gulf of Thailand (Vietnam), the Tyrrhenian Sea (Italy), the Gulf of St Vincent (Australia), the Persian Gulf (Iran) and the Northeast Atlantic Ocean (Norway). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (30 STUDIES) Reduction of unwanted catch (30 studies): Seven of seven replicated studies (including one controlled) in the northeast Atlantic Ocean, North Sea, North Atlantic Ocean, Greenland Sea, Gulf of Thailand, Tyrrhenian Sea and the Skagerrak and Kattegat found that fitting rigid or flexible size-sorting escape grids, of various types and configurations, to prawn/shrimp trawl nets reduced unwanted fish catches (non-commercial species and discarded commercial species/sizes) by allowing the escape of unwanted sharks and the other fish species monitored. Two of two before-and-after studies in the Gulf of Maine and Pacific Ocean found that after the introduction of size-sorting escape grids to trawl nets in fisheries for shrimp, the capture of non-target and unwanted fish was reduced compared to before grids were used. Eleven of 20 replicated studies (including one controlled and 19 paired and controlled) in the Tasman Sea, Coral Sea, Gulf of Carpentaria, North Sea, Indian Ocean, Bay of Biscay, Skagerrak and Kattegat, Pacific Ocean, South Atlantic Ocean, Gulf of St Vincent and Persian Gulf found that prawn/shrimp trawls with size-sorting escape grids, of various types and configurations, had lower catches of all or all but one undersized or otherwise unwanted fish and shark/ray species monitored, and unwanted total catch (fish and invertebrates), compared to trawl nets without escape grids. Two found that escape grids reduced non-target catches of most sizes of whiting and plaice and larger sizes of total fish, but increased the retention of small cod and haddock. Three studies found a variable effect of fitting escape grids to shrimp/prawn trawl nets on unwanted fish catch compared to nets with no grids, and the effect varied with year, site and grid type. Three found that grids had no effect on the reduction of unwanted fish and catches were similar for all or most of the unwanted non-commercial and commercial fish species/groups and for the total unwanted catch (fish and invertebrates). The other study found that fewer unwanted fish of 10 of 11 species/groups were retained in a shrimp/prawn trawl net with an escape grid used in combination with a diamond mesh codend with the mesh orientation turned by 90°, compared to a conventional diamond mesh net with no grid. One replicated, randomized study in the North Atlantic Ocean found that the reduction in catch of unwanted sharks depended on the type of escape grid and shrimp/prawn trawl net used. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2721https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2721Mon, 18 Jan 2021 16:42:48 +0000