Collected 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: Create small adjoining cavities or ‘swimthrough’ habitats (≤100 mm) on subtidal artificial structures Four studies examined the effects of creating small adjoining cavities or ‘swimthrough’ habitats on subtidal artificial structures on the biodiversity of those structures. Two studies were in marinas in France and Morocco, while one was in each of a lagoon in Mayotte and a port in France. COMMUNITY RESPONSE (1 STUDY) Fish community composition (1 study): One replicated, paired sites, controlled study in France found that creating small swimthrough habitats on subtidal artificial structures had mixed effects on the juvenile fish community composition on and around structure surfaces, depending on the site and survey month. Swimthrough habitats supported six species that were absent from structure surfaces without swimthroughs. Fish richness/diversity (1 study): One replicated, paired sites, controlled study in France found that creating small swimthrough habitats on subtidal artificial structures had mixed effects on juvenile fish species richness on and around structure surfaces, depending on the site. POPULATION RESPONSE (2 STUDIES) Fish abundance (2 studies): Two replicated, paired sites, controlled studies in France found that creating small swimthrough habitats on subtidal artificial structures had mixed effects on juvenile fish abundances on and around structure surfaces, depending on the species, site, survey month and/or juvenile development stage. BEHAVIOUR (3 STUDIES) Use (3 studies): One replicated, paired sites, controlled study in France found that creating small swimthrough habitats on subtidal artificial structures had mixed effects on juvenile seabream habitat use on and around structure surfaces, depending on the species and juvenile development stage. Two studies (including one replicated study) in Mayotte and Morocco reported that small swimthrough habitats, along with large swimthroughs and environmentally-sensitive material in one, were used by juvenile spiny lobsters, sea firs, adult fish and/or juvenile fish. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3436https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3436Fri, 13 Aug 2021 12:15:34 +0100Collected Evidence: Collected Evidence: Create large adjoining cavities or ‘swimthrough’ habitats (>100 mm) on subtidal artificial structures Two studies examined the effects of creating large adjoining cavities or ‘swimthrough’ habitats on subtidal artificial structures on the biodiversity of those structures. One study was in a lagoon in Mayotte and one was in a marina in southeast USA. COMMUNITY RESPONSE (1 STUDY) Fish community composition (1 study): One replicated, paired sites, controlled study in the USA reported that large swimthrough habitats created in front of a subtidal artificial structure supported fish species that were absent from structure surfaces without swimthroughs. Fish richness/diversity (1 study): One replicated, paired sites, controlled study in the USA found that creating large swimthrough habitats in front of a subtidal artificial structure increased the overall fish species richness on and around structure surfaces, but that effects varied depending on the fish size class. POPULATION RESPONSE (1 STUDY) Fish abundance (1 study): One replicated, paired sites, controlled study in the USA found that creating large swimthrough habitats in front of a subtidal artificial structure increased the overall fish abundance on and around structure surfaces, but that individual species abundances varied depending on the species, size class and survey month. BEHAVIOUR (1 STUDY) Use (1 study): One study in Mayotte reported that large swimthrough habitats created on a subtidal artificial structure, along with small swimthroughs and environmentally-sensitive material, were used by juvenile spiny lobsters and groupers, sea firs, and adult fishes from five families. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3456https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3456Mon, 13 Sep 2021 10:12:41 +0100Collected Evidence: Collected Evidence: Use environmentally-sensitive material on subtidal artificial structures Fourteen studies examined the effects of using environmentally-sensitive material on subtidal artificial structures on the biodiversity of those structures. Seven studies were on open coastlines in the United Arab Emirates, Italy, Israel, southeast Spain, and in France, the UK, Portugal and Spain. Three were in marinas in northern Israel and the UK, two were in estuaries in southeast Australia and eastern USA, one was in a lagoon in Mayotte, and one was in a port in Germany. COMMUNITY RESPONSE (11 STUDIES) Overall community composition (11 studies): Six of 11 replicated, controlled studies (including eight randomized, three paired sites and one before-and-after study) in Australia, the United Arab Emirates, Italy, Israel, the USA, the UK, Spain and Germany found that using shell-concrete or quarried rock in place of standard-concrete on subtidal artificial structures, or using ECOncreteTM in place of standard-concrete or fibreglass, along with creating texture, grooves, holes, pits and/or small ledges, altered the combined macroalgae and invertebrate community composition on structure surfaces. Three studies found that using quarried rock or blast-furnace-cement-concrete in place of standard-concrete did not alter the community composition, while one found mixed effects depending on the type of rock tested and the site. One found that using different cement mixes in concrete (including some with recycled cements) altered the community composition of native species, but not non-natives. Three of the studies also reported that ECOncreteTM surfaces with added habitats supported mobile invertebrate, non-mobile invertebrate and/or fish species that were absent from standard-concrete or fibreglass structure surfaces. Overall richness/diversity (7 studies): Three of seven replicated, controlled studies (including five randomized, two paired sites and one before-and-after study) in Italy, Israel, the USA, the UK and Spain found that using quarried rock, shell-concrete or recycled-cement-concrete in place of standard-concrete on subtidal artificial structures had mixed effects on the combined macroalgae and invertebrate species richness on structure surfaces, depending on the site, surface orientation or type of cement tested. One of the studies, along with one other, found that using shell-concrete or quarried rock did not increase the species diversity and/or richness, while one found that using recycled cement did not increase the non-native species richness. Three studies found that using ECOncreteTM, along with creating texture, grooves, holes, pits and/or small ledges, did increase the species diversity and/or richness on and around structures. Algal richness/diversity (1 study): One replicated, randomized, controlled study in the UK found that using recycled-cement-concrete in place of standard-concrete on subtidal artificial structures did not increase the diatom species richness on structure surfaces. POPULATION RESPONSE (11 STUDIES) Overall abundance (7 studies): Three of seven replicated studies (including six controlled, four randomized and one paired sites study) in the United Arab Emirates, Italy, Israel, the USA, the UK, Spain, and in France, the UK, Portugal and Spain found that using quarried rock or shell-concrete in place of standard-concrete on subtidal artificial structures did not increase the combined macroalgae and invertebrate abundance on structure surfaces. Two studies found mixed effects, depending on the type of quarried rock or concrete tested and/or the location. One found that using ECOncreteTM in place of fibreglass, along with creating textured surfaces, increased the live cover and biomass, while one found that different ECOncreteTM and standard-concrete mixes supported different cover and inorganic biomass but similar organic biomass. Algal abundance (6 studies): Four of six replicated, controlled studies (including four randomized and one paired sites study) in Australia, the United Arab Emirates, Italy, Israel and the UK found that using quarried rock or recycled-cement-concrete in place of standard-concrete on subtidal artificial structures did not increase the abundance of brown, turf or coralline macroalgae, canopy macroalgae recruits or diatoms on structure surfaces. Two studies found that using quarried rock or using ECOncreteTM, along with creating grooves, holes and pits, had mixed effects on macroalgal abundance, depending on the species group and/or site. One of the studies found that using quarried rock increased red and green macroalgal abundance. Invertebrate abundance (6 studies): Three of six replicated, controlled studies (including four randomized and one paired sites study) in Austalia, the United Arab Emirates, Italy, Israel and the UK found that using quarried rock in place of concrete on subtidal artificial structures, or using ECOncreteTM, along with creating grooves, holes and pits, had mixed effects on the abundance of non-mobile invertebrates, mobile invertebrates or coral recruits on structure surfaces, depending on the type of rock tested, the species group and/or the site. One of the studies, along with one other, found that using quarried rock did not increase the abundance of sponges, bryozoans, ascidians, mussels, barnacles, or Serpulid tubeworms, but in one it decreased Spirorbid tubeworm abundance. One study found that using shell-concrete increased bivalve abundance. One found that different ECOncreteTM and standard-concrete mixes supported different coral abundance. Fish abundance (1 study): One replicated, controlled study in Israel found that using ECOncreteTM in place of standard-concrete on subtidal artificial structures, along with creating grooves, holes and pits, had mixed effects on fish abundances, depending on the species group. BEHAVIOUR (1 STUDY) Use (1 study): One study in Mayotte reported that basalt rock surfaces created on a concrete subtidal artificial structure, along with small and large swimthroughs, were used by juvenile spiny lobsters and groupers, sea firs, and adult fishes from five families. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3470https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3470Thu, 16 Sep 2021 19:51:58 +0100
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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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