Collected Evidence: Collected Evidence: Breed for resistance traits A replicated, controlled study in Norway found increased survival levels in salmon exposed to infectious pancreatic necrosis when the family was bred for high resistance to the disease compared to a family bred for low resistance to the disease. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F735https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F735Mon, 03 Jun 2013 15:17:27 +0100Collected Evidence: Collected Evidence: Aerobic training A randomised, replicated, controlled study in Norway found higher survival rates in salmon exposed to infectious pancreatic necrosis if they had undergone aerobic training. Interval training was more effective than continuous training. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F740https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F740Mon, 03 Jun 2013 15:39:10 +0100Collected Evidence: Collected Evidence: Cease or prohibit aggregate extraction Seven studies examined the effects of ceasing or prohibiting aggregate extraction on subtidal benthic invertebrate populations. One study was in the English Channel (France), one in the Mediterranean Sea (Italy), one a global study, and four in the North Sea (UK, Belgium).   COMMUNITY RESPONSE (6 STUDIES) Overall community composition (4 studies): One global systematic review found that it took nine months to several decades for overall invertebrate community composition to recover after ceasing aggregate extraction. One before-and-after, site comparison study in the Mediterranean Sea and one of two site comparison studies in the North Sea found that after ceasing aggregate extraction overall invertebrate community composition became more similar to pre-extraction and/or natural site communities. Overall richness/diversity (5 studies): Two before-and-after, site comparison studies in the English Channel and the Mediterranean Sea and one of two site comparison studies in the North Sea found that after ceasing aggregate extraction, overall invertebrate species richness and/or diversity became more similar to that of pre-extraction and/or natural sites. The other site comparison found that species richness did not change over time and remained different to that of natural sites. One replicated, site comparison study in the North Sea found that 21 months after ceasing aggregate extractiom, invertebrate species richness was similar to that of natural sites. Worm community composition (1 study): One before-and-after study in the North Sea found that after ceasing aggregate extraction, nematode worm community composition remained different to the pre-extraction community. Worm richness/diversity (1 study): One before-and-after study in the North Sea found that after ceasing aggregate extraction, nematode worm species richness remained different to pre-extraction richness. POPULATION RESPONSE (6 STUDIES) Overall abundance (5 studies): Two before-and-after, site comparison studies in the English Channel and the Mediterranean Sea and one of two site comparison studies in the North Sea found that after ceasing aggregate extraction overall invertebrate abundance and/or biomass became more similar to that of pre-extraction and/or natural sites. The other site comparison found that abundance and biomass did not change over time and remained different to that of natural sites. One replicated, site comparison study in the North Sea found that 21 months after ceasing aggregate extraction, invertebrate abundance was similar to that of natural sites. Worm abundance (1 study): One before-and-after study in the North Sea found that after ceasing aggregate extraction, nematode worm abundance remained different to pre-extraction abundance. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2070https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2070Mon, 21 Oct 2019 14:07:13 +0100Collected Evidence: Collected Evidence: Cease or prohibit marine mining One study examined the effects of ceasing or prohibiting mining on subtidal benthic invertebrate populations. The study was in the Bering Sea (USA).   COMMUNITY RESPONSE (1 STUDY) Overall community composition (1 study): One site comparison study in the Bering Sea found that following cessation of gold mining, overall invertebrate community composition became similar to that of an unmined site. Overall richness/diversity (1 study): One site comparison study in the Bering Sea found that following cessation of gold mining, overall invertebrate richness and diversity became similar to that of an unmined site. POPULATION RESPONSE (1 STUDY) Overall abundance (1 study): One site comparison study in the Bering Sea found that following cessation of gold mining, overall invertebrate abundance and biomass became similar to that of an unmined site. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2075https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2075Mon, 21 Oct 2019 14:43:03 +0100Collected Evidence: Collected Evidence: Cease or prohibit all types of fishing Five studies examined the effects of ceasing or prohibiting all types of fishing on subtidal benthic invertebrate populations. All studies were in the North Sea (Belgium, Germany, Netherlands, UK).   COMMUNITY RESPONSE (2 STUDIES) Overall community composition (2 studies): Two site comparison studies (one before-and-after) in the North Sea found that areas closed to all fishing developed different overall invertebrate community compositions compared to fished areas. Overall species richness/diversity (2 studies): One of two site comparison studies (one before-and-after) in the North Sea found that areas closed to all fishing did not develop different overall invertebrate species richness and diversity compared to fished areas after three years, but the other found higher species richness in the closed areas after 20 years. POPULATION RESPONSE (3 STUDIES) Overall abundance (2 studies): Two site comparison studies (one before-and-after) in the North Sea found that areas closed to all fishing had similar overall invertebrate abundance and biomass compared to fished areas after three and five years. Crustacean abundance (1 study): One before-and-after, site comparison study in the North Sea found that closing a site to all fishing led to similar numbers of lobster compared to a fished site after 20 months. Crustacean condition (1 study): One before-and-after, site comparison study in the North Sea found that closing a site to all fishing led to larger sizes of lobster compared to a fished site after 20 months. OTHER (1 STUDY) Overall community energy flow (1 study): One before-after, site comparison study in the North Sea found that, during the 12–14 months after closing an area to all fishing, the invertebrate community structure (measured as energy flow) at sites within the closed area did not change, but that it increased in nearby fished sites. Species energy flow (1 study): One before-and-after, site comparison study in the North Sea found that closing an area to all fishing for 12–14 months had mixed effects on species-level energy flow. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2096https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2096Mon, 21 Oct 2019 15:32:10 +0100Collected Evidence: Collected Evidence: Cease or prohibit commercial fishing Three studies examined the effects of ceasing or prohibiting commercial fishing on subtidal benthic invertebrate populations. Two studies were in the Tasman Sea (New Zealand), the third on Gorges Bank in the North Atlantic Ocean (USA).   COMMUNITY RESPONSE (2 STUDIES) Overall community composition (1 study): One site comparison study in the Tasman Sea  found that an area closed to commercial trawling and dredging for 28 years had different overall invertebrate communities than an area subject to commercial fishing. Overall species richness/diversity (1 study): One site comparison study on Georges Bank found no difference in invertebrate species richness between an area closed to commercial fishing for 10 to 14 years and a fished area. POPULATION RESPONSE (3 STUDIES) Overall abundance (2 studies): Two site comparison studies in the Tasman Sea  and on Georges Bank found that areas prohibiting commercial fishing for 10 to 14 years and 28 years had greater overall invertebrate abundance compared to areas where commercial fishing occurred. One of the studies  also found higher biomass, while the other found similar biomass in closed and fished areas. Crustacean abundance (1 study): One replicated, site comparison study in the Tasman Sea found that in commercial fishing exclusion zones lobster abundance was not different to adjacent fished areas after up to two years. OTHER (1 STUDY) Overall community biological production (1 study): One site comparison study in the Tasman Sea  found that an area closed to commercial trawling and dredging for 28 years had greater biological production from invertebrates than an area where commercial fishing occurred. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2097https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2097Mon, 21 Oct 2019 15:41:48 +0100Collected Evidence: Collected Evidence: Cease or prohibit bottom trawling Four studies examined the effects of ceasing or prohibiting bottom trawling on subtidal benthic invertebrate populations. Two studies were in the Bering Sea (USA), one in the North Sea, and one in the Mediterranean Sea (Italy).   COMMUNITY RESPONSE (3 STUDIES) Overall community composition (2 studies): Two site comparison studies (one before-and-after, one replicated) in the North Sea and the Mediterranean Sea found that in areas prohibiting trawling for either 15 or 20 years, overall invertebrate community composition was different to that of trawled areas. Overall species richness/diversity (3 studies): Two of three site comparison studies (one paired, one before-and-after, one replicated) in the Bering Sea, the North Sea, and the Mediterranean Sea found that invertebrate diversity was higher in sites closed to trawling compared to trawled sites after either 37 or 15 years, but the other found no differences after 20 years. POPULATION RESPONSE (3 STUDIES) Overall abundance (2 studies): One of two site comparison studies (one paired, one replicated) in the Bering Sea and the Mediterranean Sea found that total invertebrate abundance was higher in sites closed to trawling compared to trawled sites after 37 years, but the other found no differences after 20 years. Both found no differences in total invertebrate biomass. Unwanted catch overall abundance (1 study): One replicated, before-and-after, site comparison study in the Bering Sea found that during the three years after closing areas to all bottom trawling, unwanted catch of crabs appeared to have decreased, while no changes appeared to have occurred in nearby trawled areas. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2099https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2099Tue, 22 Oct 2019 08:41:27 +0100Collected Evidence: Collected Evidence: Cease or prohibit dredging Four studies examined the effects of ceasing or prohibiting dredging on subtidal benthic invertebrate populations. One study was in the North Atlantic Ocean (Portugal), one in the South Atlantic Ocean (Argentina), one in the English Channel and one in the Irish Sea (UK).   COMMUNITY RESPONSE (3 STUDIES) Overall community composition (3 studies): One of three site comparison studies (one replicated, one before-and-after) in Atlantic Ocean and the Irish Sea found that after ceasing dredging, overall invertebrate community composition was different to that in dredged areas. The other two found that communities remained similar in dredged and non-dredged areas. Overall richness/diversity (3 studies): One of three site comparison studies (one replicated, one before-and-after) in Atlantic Ocean and the Irish Sea found that after ceasing dredging, large (macro-) invertebrate diversity was higher but small (meio-) invertebrate diversity was lower compared to dredged areas. The other two found that overall diversity remained similar in dredged and non-dredged areas. POPULATION RESPONSE (3 STUDIES) Overall abundance (3 studies): One of three site comparison studies (one replicated, one before-and-after) in Atlantic Ocean and the Irish Sea found that four years after ceasing dredging, large (macro-) and small (meio-) invertebrate abundance and/or biomass appeared higher to that in dredged areas. The other two found that abundance and/or biomass remained similar in dredged and non-dredged areas after either two or six years. Tunicate abundance (1 study): One replicated, site comparison study in the English Channel found that a year after ceasing dredging in three areas, abundance of ascidians/sea squirts (tunicates) was similar to that in dredged areas. Bryozoan abundance (1 study): One replicated, site comparison study in the English Channel found that a year after ceasing dredging in three areas, abundance of bryozoan was higher than in dredged areas. Crustacean abundance (1 study): One replicated, site comparison study in the English Channel found that a year after ceasing dredging in three areas, abundance of spider crabs was higher than in dredged areas, but abundance of edible crab was similar. Cnidarian abundance (1 study): One replicated, site comparison study in the English Channel found that a year after ceasing dredging in three areas, abundance of sea fans was higher than in dredged areas. Sponge abundance (1 study): One replicated, site comparison study in the English Channel found that a year after ceasing dredging in three areas, abundance of sponges was higher than in dredged areas. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2101https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2101Tue, 22 Oct 2019 08:53:41 +0100Collected Evidence: Collected Evidence: Cease or prohibit all towed (mobile) fishing gear Eight studies examined the effects of ceasing or prohibiting all towed fishing gear on subtidal benthic invertebrate populations. One study was in the Limfjord (Denmark), two in the English Channel (UK), three in Georges Bank in the North Atlantic Ocean (USA and Canada), one in the Ria Formosa lagoon (Portugal), and one in the Irish Sea (Isle of Man).   COMMUNITY RESPONSE (4 STUDIES) Overall community composition (3 studies): Two of three replicated, site comparison studies in the Limfjord and the English Channel, found that areas excluding towed fishing gear for either an unspecified amount of time or two to 23 years had different overall invertebrate community composition compared to areas where towed-fishing occurred and one found that ceasing towed-gear fishing for nine years had mixed effects. Overall species richness/diversity (3 studies): Two replicated, site comparison studies in the English Channel reported that areas excluding towed fishing gear for either an unspecified amount of time or two to 23 years had different or greater invertebrate species richness and diversity to areas where towed-fishing occurred. One site comparison study in Georges Bank found no difference in invertebrate species richness between an area closed to mobile fishing gear for 10 to 14 years and a fished area. POPULATION RESPONSE (3 STUDIES) Overall abundance (3 studies): Two site comparison studies (one replicated) in the English Channel and Georges Bank found that sites excluding towed gear for either two to 23 years or 10 to 14 years had greater overall invertebrate biomass compared to sites where towed-gear fishing occurred, but one also found that abundance was similar in both areas. One replicated, controlled, before-and-after study in the Ria Formosa lagoon found that ceasing towed gear for 10 months led to increases in the cover of mobile but not sessile Mollusc abundance (2 studies): Two site comparison studies (one replicated) in the Irish Sea and the English Channel found that areas closed to towed fishing gear for either two to 23 years or 14 years had more scallops compared to adjacent fished areas. Mollusc condition (1 study): One site comparison study the Irish Sea found that an area closed to towed fishing gear for 14 years had higher proportions of older and larger scallops compared to an adjacent fished area. Starfish abundance (1 study): One replicated, site comparison study in Georges Bank found more starfish in areas closed to towed fishing gear for five to nine years compared to adjacent fished areas. Starfish condition (1 study): One replicated, site comparison study in Georges Bank found that starfish arm length was similar in areas closed to towed fishing gear for five to nine years and adjacent fished areas. OTHER (1 STUDY) Overall community biological production (1 study): One before-and-after, site comparison study in Georges Bank found an increase in the biological production from invertebrate in sites closed to towed fishing gear for approximately five years compared to adjacent fished sites. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2102https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2102Tue, 22 Oct 2019 08:58:29 +0100Collected Evidence: Collected Evidence: Add chemicals or minerals to sediments to remove or neutralise pollutants Two studies examined the effects of adding chemicals or minerals to sediments to remove or neutralise pollutants on subtidal benthic invertebrate populations. Both studies evaluated the use of coal ash in Hiroshima Bay (Japan).   COMMUNITY RESPONSE (1 STUDY) Overall richness/diversity (1 study): One controlled, before-and-after study in Hiroshima Bay found that adding coal ash increased invertebrate species richness in winter but not summer compared to untreated sites. POPULATION RESPONSE (2 STUDIES) Overall abundance (2 studies): One controlled, before-and-after study in Hiroshima Bay found that adding coal ash increased invertebrate abundance in winter but not summer compared to untreated sites. One controlled study in Hiroshima Bay found that one of two types of coal ash increased combined invertebrate and fish abundance, but not biomass. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2176https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2176Tue, 22 Oct 2019 12:27:40 +0100Collected Evidence: Collected Evidence: Cease or prohibit aquaculture activity Two studies examined the effects of ceasing or prohibiting aquaculture activity on subtidal benthic invertebrate populations. Both studies were in the Mediterranean Sea (Italy and Spain).   COMMUNITY RESPONSE (2 STUDIES) Overall community composition (1 study): One before-and-after, site comparison study in the Mediterranean Sea found that after ceasing aquaculture activity invertebrate community composition remained different to that of an unfarmed site. Worm community composition (1 study): One before-and-after, site comparison study in the Mediterranean Sea found that after ceasing aquaculture activity worm community composition community composition remained different to that of an unfarmed site. POPULATION RESPONSE (2 STUDIES) Overall abundance (1 study): One before-and-after, site comparison study in the Mediterranean Sea found that after ceasing aquaculture activity overall invertebrate abundance was similar to an unfarmed site. Worm abundance (1 study): One before-and-after, site comparison study in the Mediterranean Sea found that after ceasing aquaculture activity abundance of health-indicating worms increased, and abundance of pollution-indicating worms decreased. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2185https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2185Tue, 22 Oct 2019 12:46:43 +0100Collected Evidence: Collected Evidence: Cease or prohibit all (mobile and static) fishing gears that catch bottom (demersal) species Three studies examined the effects of ceasing or prohibiting mobile and static fishing gears that catch bottom (demersal) species in an area on marine fish populations. One study was in each of the Greenland Sea (Iceland), the North Pacific Ocean (Canada) and the North Atlantic Ocean (USA/Canada). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (3 STUDIES) Abundance (3 studies): One of three replicated, controlled studies (one paired) in the Greenland Sea, North Pacific Ocean and the North Atlantic Ocean found that an area where fishing gears targeting bottom-dwelling species had been prohibited for 15 years had higher numbers of larger and older cod than openly fished areas. One study found that fish densities in areas closed to mobile and static bottom fish gears (trawls and longlines) for at least 11 years varied between fish species/groups, and also with depth and temperature. The other study found that prohibiting mobile and static bottom fish gears (trawls and hook and line) in protected areas for 2–7 years had no effect on fish densities compared to non-protected areas. Condition (2 studies): One of two replicated, controlled studies (one paired) in the Greenland Sea and the North Atlantic Ocean found that cod had better growth in areas closed for 5-15 years to mobile and static gears that targeted bottom-dwelling fish, compared to openly fished areas. The other study found that fish size varied between areas closed and open to bottom fish gears (trawls and longlines) and was also affected by depth and temperature. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2654https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2654Thu, 12 Nov 2020 14:42:52 +0000Collected 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 non-towed (static) fishing gear One study examined the effects of ceasing or prohibiting all non-towed (static) fishing gears on marine fish populations. The study was in the Coral Sea (Australia).   COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): One replicated, site comparison study in the Coral Sea found that in areas closed to non-towed fishing gears overall shark abundance was higher when sampled with longlines but not gillnets compared to areas where commercial gillnets were permitted. Condition (1 study): One replicated, site comparison study in the Coral Sea found that in areas closed to non-towed fishing gears shark length was greater for two of five species/groups, similar for two and dependent on sampling gear for one species, compared to areas where commercial gillnets were permitted. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2670https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2670Thu, 19 Nov 2020 16:10:49 +0000Collected Evidence: Collected Evidence: Cease or prohibit line fishing One study examined the effects of ceasing or prohibiting line fishing in an area on marine fish populations. The study was in the Indian Ocean (South Africa). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY)  Abundance (1 study): One site comparison study in the Indian Ocean found that prohibiting offshore line fishing and all other boat-based fishing in a zone of a marine protected area resulted in higher abundances of four of four fish species over-exploited by line fishing, compared to two zones where boat-based line and spear fishing was permitted. Condition (1 study): One site comparison study in the Indian Ocean found that in a zone of a marine protected area closed to offshore line fishing and all other boat-based fishing for two to seven years, four of four fish species over-exploited by line fishing were larger, compared to two zones where boat-based line and spear fishing was permitted. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2671https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2671Thu, 19 Nov 2020 16:41:12 +0000Collected Evidence: Collected Evidence: Cease or prohibit mobile fishing gears that catch bottom (demersal) species and are dragged across the seafloor Ten studies examined the effects of ceasing or prohibiting mobile fishing gears that catch bottom (demersal) species and are dragged across the seafloor on marine fish populations. Two studies were in each of the North Atlantic Ocean (Canada, Portugal), the Indian Ocean (Tasmania, Kenya) and the Mediterranean Sea. One study was in each of the North Sea (Denmark), the Arafura Sea (Australia), the Coral Sea (Australia) and the Gulf of Mexico (USA). COMMUNITY RESPONSE (3 STUDIES)  Richness/diversity (3 studies): Two of three site comparison studies (one replicated and randomized, and one before-and-after) in the North Sea, Indian Ocean and Gulf of Mexico found that the number of fish species, the fish assemblage and overall species richness and diversity (fish and invertebrates combined) varied between areas with different exposures to bottom trawling, and was also dependent on bottom depth and habitat type. The other study reported no effect of closing an area to all towed bottom fishing gears on the species richness of bottom-dwelling fish after 10 years and compared to areas open to trawling.  POPULATION RESPONSE (8 STUDIES) Abundance (5 studies): Two of three replicated studies (one controlled and before-and-after, and two site comparison) and one of two before-and-after studies (one site comparison) in the North Sea, Arafura Sea, North Atlantic Ocean and the Mediterranean Sea found that ceasing or prohibiting fishing with towed bottom gears resulted in higher total fish biomass after 15 years, higher biomass of adult red mullet after 14 years and increased abundances of long-snouted, but not short-snouted, seahorses after one year, compared to openly fished areas. The other two studies found that a ban on towed bottom fishing gears for five and 10 years had no effect on the abundance of bottom-dwelling fish species after closure compared to before, or the abundance and biomass of fish and invertebrate species (combined) compared to areas open to towed gears/trawling. Reproductive success (2 studies): One of two before-and-after studies (one site comparison) in the North Atlantic Ocean and Mediterranean Sea found that after the closure of an area to all bottom-towed fishing gears for 14 years, recruitment of young red mullet had increased. The other study found that an area closed to bottom trawling did not have higher recruitment of young haddock seven years after closure and compared to a trawled area. Survival (1 study): One before-and-after, site comparison study in the North Atlantic Ocean found that closing an area to bottom trawling did not increase the survival of young haddock seven years after closure, and compared to a trawled area. Condition (5 studies): One of four replicated studies (two site comparison and one randomized, site comparison) and one before-and-after study in the Arafura Sea, Mediterranean Sea, Gulf of Mexico and the Indian Ocean found that areas prohibiting bottom towed fishing gears had larger sizes of adult red mullet 14 years after closure than before. Two studies found that the effect on fish size of closing areas to towed bottom gears for 3–6 years or areas with no bottom fishing activity varied between individual fish groups and with habitat type, compared to fished areas. The other two found that areas closed to bottom trawling for five years and 15 years had no effect on the overall size of fish and invertebrate species combined or average fish weight, compared to trawled areas. BEHAVIOUR (0 STUDIES) OTHER (2 STUDIES) Reduce unwanted catch (1 study): One randomized, replicated, site comparison study in the Coral Sea found no reduction in the biomass of non-commercial unwanted catch (fish and invertebrate discard) or in the number of ‘common’ and ‘rare’ discard species in areas closed to trawling for seven years compared to trawled areas. Catch abundance (1 study): One replicated, before-and-after study in the Indian Ocean found that areas prohibiting beach and all other seine nets for 3–6 years found overall fish catch rates were higher, and catch rates of individual fish groups were variable, compared to unrestricted areas. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2673https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2673Fri, 20 Nov 2020 12:12:24 +0000Collected Evidence: Collected Evidence: Cease or prohibit customary fishing (indigenous fishing for cultural and community needs) One study examined the effects of ceasing or prohibiting customary fishing in an area, on marine fish populations. The study was in the Bismark Sea (Papua New Guinea). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): One site comparison study in the Bismark Sea found a higher abundance of only one of seven fish species in an area closed to customary fishing for eight years, compared to an area open to customary fishing. BEHAVIOUR (1 STUDY) Behaviour change (1 study): One site comparison study in the Bismark Sea found that in an area closed to customary fishing for eight years, six of seven fish species had a lower flight response distance compared to an area open to customary fishing, making them more vulnerable to capture with spear guns. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2675https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2675Fri, 27 Nov 2020 15:46:26 +0000Collected Evidence: Collected Evidence: Allow only small-scale, traditional (artisanal) fishing One study examined the effects of allowing only small-scale traditional (artisanal) fishing in an area on marine fish populations. The study was in the Adriatic Sea (Italy). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Commercial catch abundance (1 study): One site comparison study in the Adriatic Sea found that a marine protected area zone allowing only artisanal fishing activity for three years had higher overall commercial catch rates of five of seven species compared to unprotected areas openly fished. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2678https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2678Fri, 27 Nov 2020 16:09:39 +0000Collected Evidence: Collected Evidence: Allow periodic fishing only One study examined the effects of allowing fishing only periodically in an area on marine fish populations. The study was in the Coral Sea (Vanuatu). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): One replicated, paired, site comparison study in the Coral Sea found that protected areas fished only for short periods over an 18 month to six-year period, had greater biomass than openly fished areas and similar fish biomass as areas permanently closed to fishing for six years. BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Catch abundance (1 study): One replicated, paired, site comparison study in the Coral Sea found that protected areas only fished for short periods over an 18 month to six year period, had higher fish catch rates than openly fished areas. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2679https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2679Fri, 27 Nov 2020 16:20:22 +0000Collected Evidence: Collected Evidence: Cease or prohibit all fishing activity in a marine protected area with limited exceptions Four studies examined the effects of ceasing or prohibiting all fishing activity in a marine protected area with limited exceptions on marine fish populations. One study was in each of the Pacific Ocean (USA), the Caribbean Sea (US Virgin Islands), the Great Barrier Reef (Australia) and the Skagerrak (Norway). COMMUNITY RESPONSE (1 STUDY) Richness/diversity (1 study): One site comparison study in the Caribbean Sea found that in marine protected areas closed to all fishing with limited exceptions for up to seven years, there was lower total fish species richness compared to unprotected areas. POPULATION RESPONSE (3 STUDIES) Abundance (2 studies): One replicated, site comparison study in the Pacific Ocean found that abundance of copper rockfish, quillback rockfish, china rockfish and lingcod was similar between non-voluntary and voluntary ‘no-take’ reserve sites where all fishing with limited exceptions had been prohibited for one to eight years, and sites open to fishing. One site comparison study in the Caribbean Sea found that restricting all fishing activity except for bait fishing in marine protected areas for seven years resulted in similar total fish biomass and lower total fish density, compared to unprotected areas. Survival (1 study): One replicated, controlled, before-and-after study in the Skagerrak found that cod survival increased inside a marine protected area in the eight years after almost all fishing was prohibited, compared to outside areas fished with a wider range of gear types. BEHAVIOUR (1 STUDY) Use (1 study): One replicated study in the Great Barrier Reef found that immature pigeye sharks and adult spottail sharks were detected frequently and over long time periods inside marine protected areas five years after prohibiting almost all fishing except restricted line fishing and bait netting, thus reducing the overall likelihood of fishing mortality. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2681https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2681Fri, 27 Nov 2020 16:53:17 +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: Attach an electropositive deterrent to fishing gear Nine studies examined the effect of attaching an electropositive deterrent to fishing gear on marine fish populations. Three studies were in the Atlantic Ocean (USA, Canada, Bahamas). One study was in each of the Gulf of Alaska (USA), the South Pacific Ocean (Australia) and the Tasman Sea (Australia). One study was a global systematic review and two studies were in laboratory facilities (USA).  COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (4 STUDIES) Behaviour change (4 studies): Three of four replicated studies (one paired and controlled, one randomized and controlled, one randomized, and one controlled) in the Atlantic Ocean, Tasman Sea, and in laboratory conditions, found that the presence of potentially deterrent materials attached near the bait reduced the frequency of feeding attempts and bait consumption of spiny dogfish, great hammerhead and draughtboard sharks compared to the absence of deterrent materials. The other study found that a potentially deterrent material did not reduce bait consumption by bonnethead and young lemon sharks compared to non-deterrents. One of the studies also found that the bait consumption behaviour of commercially valuable Pacific halibut was unaffected by deterrent materials. OTHER (5 STUDIES) Reduction of unwanted catch (5 studies): Two of four replicated, controlled studies (one randomized) in the Gulf of Alaska, the Pacific Ocean and the Atlantic Ocean found that fishing gear (longlines and traps) fitted with electropositive deterrent materials caught fewer unwanted spiny dogfish, longnose skate, sharks and rays, and fewer undersized halibut, compared to standard fishing gear or gears with non-deterrent materials. The other two studies, and a global systematic review found that electropositive deterrents on fishing gear resulted in similar catches of unwanted spiny dogfish, sharks (total catch), blue shark and sharks and rays (total catch), compared to gear with no deterrents. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2696https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2696Thu, 03 Dec 2020 12:05:21 +0000Collected Evidence: Collected Evidence: Attach acoustically reflective objects to fishing gear Two studies evaluated the effects on marine mammals of attaching acoustically reflective objects to fishing gear. One study was in the Timor Sea and Arafura Sea (Australia) and one was in the Gulf of Alaska (USA). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (2 STUDIES) Reduction in entanglements/unwanted catch (1 study): One controlled study in the Timor Sea and Arafura Sea found that attaching metallic bead chains to fishing nets did not reduce the number of dolphin entanglements. Human-wildlife conflict (1 study): One controlled study in the Gulf of Alaska found that attaching acrylic beads next to fishing hooks did not reduce predation on fish catches by sperm whales. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2806https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2806Thu, 04 Feb 2021 17:20:11 +0000Collected Evidence: Collected Evidence: Cease or prohibit activities that cause disturbance in sensitive areas for marine and freshwater mammals Two studies evaluated the effects of prohibiting activities that cause disturbance in sensitive areas for marine mammals. One study was in the Kattegat Sea (Denmark) and one in the Indian Ocean (Australia). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): One before-and-after study in the Kattegat sea found that harbour porpoise activity increased at a stony reef after fishing was prohibited and the reef was restored with boulders. BEHAVIOUR (1 STUDY) Behaviour change (1 study): One site comparison study in the Indian Ocean found that a beach where human access was fully prohibited had fewer Australian sea lions showing aggression or retreating compared to a beach where access was partly prohibited. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2917https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2917Mon, 08 Feb 2021 16:33:04 +0000Collected Evidence: Collected Evidence: Add lights to fishing gear Five studies evaluated the effects of adding lights to fishing gear on reptile populations. Two studies were in the Baja California peninsula (Mexico) and one was in each of Sechura Bay (Peru), the Atlantic and North Pacific and the Adriatic Sea. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Survival (1 study): One randomized, controlled, paired study in the Adriatic Sea found that no loggerhead turtles were caught and died in in gillnets with UV lights whereas some did in nets without lights. BEHAVIOUR (0 STUDIES) OTHER (5 STUDIES) Unwanted catch (5 studies): Four controlled studies (including three replicated and two paired studies) in the Baja California peninsula, Sechura Bay and the Adriatic Sea found that gillnets with LED lights, light sticks or UV lights caught fewer green turtles and loggerhead turtles than nets without lights. One replicated study in the Atlantic and North Pacific found mixed effects of increasing the number of light sticks on longlines on the chance of catching loggerhead and leatherback turtles. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3554https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3554Wed, 08 Dec 2021 13:59:36 +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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