Collected Evidence: Collected Evidence: Mark trawler warp cables to reduce seabird collisionsA replicated, controlled study in Argentina found that seabird mortality from collisions with trawler warp cables was much lower when the cables were marked.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F305https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F305Tue, 24 Jul 2012 18:15:42 +0100Collected Evidence: Collected Evidence: Integrated aquaculture systems One replicated, controlled study in the USA reported greater growth of scallops grown next to fish farms. A study in Canada found that blue mussels absorbed waste from a salmon farm. A replicated, controlled study in Scotland reported enhanced algal growth when placed adjacent to fish farms. One study in Spain found no evidence that oyster and mussels were feeding on fish farm waste.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F932https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F932Fri, 25 Oct 2013 13:57:09 +0100Collected Evidence: Collected Evidence: Leave mining waste (tailings) in place following cessation of disposal operations One study examined the effects of leaving mining waste (tailings) in place following cessation of disposal operations on subtidal benthic invertebrate populations. The study was in Auke Bay (USA).   COMMUNITY RESPONSE (1 STUDY) Overall community composition (1 study): One replicated, paired, controlled study in Auke Bay found that plots where mine tailings were left in place had similar invertebrate community composition as plots where tailings had been removed, but both had different communities to plots of natural sediment. Overall richness/diversity (1 study): One replicated, paired, controlled study in Auke Bay found that plots where mine tailings were left in place had similar invertebrate species richness as plots where tailings had been removed, but both had lower richness compared to plots of natural sediment. POPULATION RESPONSE (1 STUDY) Overall abundance (1 study): One replicated, paired, controlled study in Auke Bay found that plots where mine tailings were left in place had similar invertebrate overall abundance and biomass as plots where tailings had been removed. While plots with and without tailings had similar abundances to plots of natural sediment, their biomasses were higher. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2077https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2077Mon, 21 Oct 2019 14:45:29 +0100Collected Evidence: Collected Evidence: Install physical barriers to prevent trawling One study examined the effects of installing physical barriers to prevent trawling on subtidal benthic invertebrate populations. The study was in the Bay of Biscay (Spain).   COMMUNITY RESPONSE (1 STUDY) Overall community composition (1 study): One before-and-after study in the Bay of Biscay found that one to four years after installing artificial reefs as physical barriers to prevent trawling invertebrate community composition changed. POPULATION RESPONSE (1 STUDY) Overall abundance (1 study): One before-and-after study in the Bay of Biscay found that one to four years after installing artificial reefs as physical barriers to prevent trawling overall invertebrate biomass increased. Echinoderm abundance (1 study): One before-and-after study in the Bay of Biscay found that one to four years after installing artificial reefs as physical barriers to prevent trawling the biomass of sea urchins and starfish increased. Molluscs abundance (1 study): One before-and-after study in the Bay of Biscay found that one to four years after installing artificial reefs as physical barriers to prevent trawling the biomass of gastropods (sea snails), of one species of cuttlefish, and of two species of octopus increased. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2112https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2112Tue, 22 Oct 2019 09:40:04 +0100Collected Evidence: Collected Evidence: Limit, cease or prohibit the dumping of sewage sludge Two studies examined the effects of ceasing or prohibiting the dumping of sewage sludge on subtidal benthic invertebrate populations. One study was in the New York Bight (USA), one in the North Sea (UK).   COMMUNITY RESPONSE (2 STUDIES) Overall community composition (2 studies): One before-and-after, site comparison study in the New York Bight found that after ceasing sewage sludge dumping, overall invertebrate community composition became more similar to less disturbed sites. One replicated, site comparison study in the North Sea found that overall invertebrate community composition changed but remained different to that of natural sites. POPULATION RESPONSE (2 STUDIES) Overall abundance (1 study): One replicated, site comparison study in the North Sea found that after ceasing sewage sludge dumping, overall invertebrate abundance became similar to that of natural sites. Worm abundance (1 study): One before-and-after, site comparison study in the New York Bight found that after ceasing sewage sludge dumping, abundance of pollution-indicator polychaete worms decreased and became similar to that of natural sites. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2179https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2179Tue, 22 Oct 2019 12:31:08 +0100Collected Evidence: Collected Evidence: Leave a fallow period during fish/shellfish farming Three studies examined the effects of leaving a fallow period during fish farming on subtidal benthic invertebrate populations. Two studies were in the Tasman Sea (Australia), and one in the North Pacific Ocean (USA).   COMMUNITY RESPONSE (3 STUDIES) Overall community composition (2 study): Two replicated, before-and-after, site comparison study in the Tasman Sea found that after a fallow period invertebrate community composition became similar to that occurring before the fish were added but remained different to communities at sites without fish farms. Worm community composition (1 study): One replicated, before-and-after, site comparison study in the North Pacific Ocean found that after a fallow period polychaete worm community composition changed but remained different to communities at sites without fish farms. Worm richness/diversity (1 study): One replicated, before-and-after, site comparison study in the North Pacific Ocean found that after a fallow period polychaete worm diversity did not change and remained lower compared to sites without fish farms. POPULATION RESPONSE (2 STUDIES) Worm abundance (2 studies): Two replicated, before-and-after, site comparison studies in the Tasman Sea and the North Pacific Ocean found that following a fallow period, abundances of pollution-indicator polychaete worms decreased, but remained higher compared to sites without fish farms. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2191https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2191Tue, 22 Oct 2019 13:02:17 +0100Collected Evidence: Collected Evidence: Landscape or artificially enhance the seabed (natural habitats) Three studies examined the effects of landscaping or artificially enhancing the seabed on subtidal benthic invertebrates. One study was in the North Sea (UK), one in the Westerschelde estuary (Netherlands), and one in the Persian Gulf (Kuwait).   COMMUNITY RESPONSE (3 STUDIES) Overall community composition (2 studies): One controlled, before-and after study in the North Sea found that following addition of gravels, invertebrate community composition became more similar to natural seabed communities. One before-and-after, site comparison study in the Westerschelde estuary found no change in invertebrate community composition following addition of sedimentary dredge material. Overall richness/diversity (3 studies): One controlled, before-and after study in the North Sea and one site comparison study in the Persian Gulf found that invertebrate species richness increased following addition of gravels or coral and limestone rubbles, and one also found that richness became similar to natural seabed. One before-and-after, site comparison study in the Westerschelde estuary found no change in species richness following addition of sedimentary dredged material. POPULATION RESPONSE (3 STUDIES) Overall abundance (3 studies): One controlled, before-and after study in the North Sea and one site comparison study in the Persian Gulf found that invertebrate abundance and biomass increased following addition of gravels or coral and limestone rubbles, and one also found that abundance became similar to natural seabed. One before-and-after, site comparison study in the Westerschelde estuary found no change in invertebrate abundance and biomass following addition of sedimentary dredge material. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2253https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2253Wed, 23 Oct 2019 09:56:38 +0100Collected Evidence: Collected Evidence: Locate artificial reefs near aquaculture systems to benefit from nutrient run-offs Two studies examined the effects of locating artificial reefs near aquaculture systems to benefit from nutrient run-offs on subtidal benthic invertebrate populations. One study was in the Gulf of Aqaba (Israel and Jordan), and one in the Mediterranean Sea (Spain).   COMMUNITY RESPONSE (1 STUDY) Overall community composition (1 study): One controlled study in the Mediterranean Sea found that an artificial reef located under aquaculture cages had similar invertebrate community composition to artificial reefs located at sites without aquaculture cages. POPULATION RESPONSE (1 STUDY) Overall abundance (1 study): One controlled study in the Gulf of Aqaba found that an artificial reef located at an aquaculture site had similar invertebrate biomass growing on it compared to an artificial reef located at a site without aquaculture cages. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2260https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2260Wed, 23 Oct 2019 10:51:01 +0100Collected Evidence: Collected Evidence: Install exclusion and/or escape devices for mammals on fishing nets Seven studies evaluated the effects on marine mammals of installing exclusion and/or escape devices on fishing nets. Four studies were in the Indian Ocean (Australia, Tasmania) and/or Tasman Sea (Tasmania) and three studies were in the South Atlantic Ocean (South Georgia). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Survival (2 studies): One study in the Indian Ocean found that less than one third of common bottlenose dolphins exited escape hatches on trawl nets alive. One replicated study in the Tasman Sea and Indian Ocean found that fewer fur seals died in exclusion devices with large escape openings than in those with small openings. BEHAVIOUR (0 STUDIES) OTHER (5 STUDIES) Reduction in entanglements/unwanted catch (5 studies): Three studies (including two controlled studies) in the South Atlantic Ocean and Indian Ocean found that installing exclusion and/or escape devices on trawl nets reduced the number of trapped or entangled Antarctic fur seals and common bottlenose dolphins. One before-and-after study in the Indian Ocean found that installing exclusion and escape devices on trawl nets reduced common bottlenose dolphin entanglements for three of four fishing vessels. One study in the South Atlantic Ocean found that modifying an exclusion and escape device by enlarging and relocating the escape panel resulted in fewer Antarctic fur seal entanglements. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2823https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2823Fri, 05 Feb 2021 15:39:04 +0000Collected Evidence: Collected Evidence: Introduce and enforce regulations for marine and freshwater mammal watching tours Four studies evaluated the effects of introducing regulations for marine and freshwater mammal watching tours on marine mammals. One study was in each of the North Atlantic Ocean (the Azores), the Cananéia estuary (Brazil), the South Pacific Ocean (Australia) and the Bass Strait (Australia). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (4 STUDIES) Behaviour change (4 studies): Two controlled studies in the North Atlantic Ocean and South Pacific Ocean found that when whale-watching vessels followed approach regulations, fewer sperm whales and humpback whale pods changed their behaviours (e.g. swimming speed, aerial displays) or avoided the vessels compared to when regulations were not followed, but direction of movement and diving patterns or diving behaviours did not differ. One replicated, controlled study in the Cananéia estuary found that when tour boats followed approach regulations, fewer Guiana dolphins displayed negative behaviours (e.g. moving away, diving, groups separating). One study in the Bass Strait found that when boats approached a seal colony to 75 m, more seals remained on shore than when boats approached to 25 m. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2838https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2838Fri, 05 Feb 2021 16:16:26 +0000Collected Evidence: Collected Evidence: Involve fishers and stakeholders in co-management Three studies examined the effect of involving fishers and stakeholders in co-management on marine fish populations. One study was in each of the Indian Ocean, the South China Sea (Vietnam) and the Pacific Ocean (Tonga).  COMMUNITY RESPONSE (1 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): One before-and-after study the Indian Ocean found that involving fishers and stakeholders in co-management increased overall fish abundance, but abundance varied between species groups, nine years after implementation compared to before. BEHAVIOUR (0 STUDIES) OTHER (2 STUDIES) Reduction of fishing effort (1 study): One before-and-after study in the Pacific Ocean found that in the five years after implementation of a new co-management system there was no decrease in overall fishing effort in the managed area. Commercial catch abundance (1 study): One before-and-after study in the Pacific Ocean found no increase in total fish catch rates and a decrease in catch rates of half of the six species groups individually inside an area with a new co-management system after five years. Improved compliance/reduction of illegal fishing activity (1 study): One before-and-after study in the South China Sea reported that after co-management was established in an area there was a decrease in illegal fishing using destructive fishing gears. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2910https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2910Mon, 08 Feb 2021 16:20:11 +0000Collected Evidence: Collected Evidence: Legally protect habitat for marine and freshwater mammals Four studies evaluated the effects of legally protecting habitat for marine and freshwater mammals. One study was in each of the North Atlantic Ocean (Portugal), the South Pacific Ocean (New Zealand), the North Sea (UK) and the Port River estuary (Australia). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (4 STUDIES) Abundance (2 studies): One before-and-after study in the North Atlantic Ocean found that a population of Mediterranean monk seals increased during eight years after the islands they inhabited were legally protected. One before-and-after study in the North Sea found that a population of bottlenose dolphins was estimated to be a similar size before and after part of its range was protected. Survival (2 studies): One before-and-after study in the South Pacific Ocean found that the survival rate of Hector’s dolphins was higher after a coastal area was legally protected than before. One before-and-after study in the Port River estuary found that after the area became legally protected a similar number of Indo-Pacific bottlenose dolphin strandings were recorded compared to before protection, but the number of strandings caused by humans decreased. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2915https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2915Mon, 08 Feb 2021 16:29:11 +0000Collected Evidence: Collected Evidence: Introduce seeds of non-woody plants: brackish/saline wetlands Eight studies evaluated the effects, on vegetation, of introducing seeds of emergent, non-woody plants to brackish/saline wetlands. There were three studies in the USA, two in the Netherlands and two in China. The other study was a global systematic review. VEGETATION COMMUNITY   VEGETATION ABUNDANCE Individual species abundance (4 studies): Four replicated studies quantified the effect of this action on the abundance of individual plant species. One study in an estuary in China also gave a before-and-after comparison, and reported higher density and biomass of seablite Suaeda salsa five months after sowing its seeds than on the bare sediment present before sowing. VEGETATION STRUCTURE Height (1 study): One replicated study on a mudflat in the Netherlands reported that the average height of surviving common cordgrass Spartina anglica plants increased, between one and six months after sowing cordgrass seeds. OTHER            Germination/emergence (5 studies): Five replicated studies in the Netherlands, the USA and China quantified germination rates of seeds sown into intertidal areas. Some seeds germinated in all five studies, at a rate of <1% to 25%. Two studies reported that no seeds germinated for some species and/or in some environments. Survival (3 studies): One replicated study in a salt marsh in the Netherlands quantified survival rates of individual germinated seedlings: 0–83% over their first growing season, depending on species and site conditions. Another replicated study in a salt marsh in the Netherlands reported that after two growing seasons, common cordgrass Spartina anglica was absent from 90% of plots in which had been sown. One global systematic review reported variable survival of herbs sown (or planted) in salt marshes: 0% to ≥95% after 20 days to 13 years, depending on the study. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3265https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3265Sat, 10 Apr 2021 15:35:13 +0100Collected Evidence: Collected Evidence: Introduce tree/shrub seeds or propagules: brackish/saline wetlands Nineteen studies evaluated the effects, on vegetation, of introducing seeds or propagules of trees/shrubs to brackish/saline wetlands. All 19 studies involved planting mangrove propagules: seven in Asia, five in North America, three in Central America, two in Oceania, one in South America and one globally. Three studies in the USA shared some study sites. VEGETATION COMMUNITY Overall extent (2 studies): Two studies in the USA and Sri Lanka simply quantified the area of mangrove vegetation present 6–14 years after planting propagules (along with other interventions). Relative abundance (1 study): One replicated, paired, site comparison study in the USA reported that mangrove forests created by planting propagules (after reprofiling) supported a different relative abundance of tree species to natural forests, after 7–15 years. Tree/shrub richness/diversity (2 studies): Two replicated, site comparison studies in the USA reported that mangrove forests created by planting propagules (along with other interventions) contained a similar number of tree species to mature natural forests, after 7–30 years. VEGETATION ABUNDANCE Tree/shrub abundance (3 studies): Three replicated, site comparison studies of coastal sites in the USA and the Philippines reported that where mangrove forests developed after planting propagules (along with other interventions), trees were typically more dense than in mature natural forests. VEGETATION STRUCTURE Overall structure (1 study): One replicated, site comparison study in the USA reported that mangrove forests created by planting propagules (along with other interventions) had a different overall physical structure to mature natural forests, after 17–30 years. Height (4 studies): Four studies (three replicated) in Thailand, the USA, Mexico and the United Arab Emirates simply quantified the height of surviving mangrove trees for up to 16 years after sowing seeds or planting propagules; in all of these studies, the average height increased over time. Diameter/perimeter/area (3 studies): Two site comparison studies (one also replicated and paired) in the USA reported that mangrove forests created by planting propagules (after reprofiling) contained thinner trees, on average, than mature natural forests, after 7–18 years. One study in a coastal area planted with mangrove propagules in Thailand reported that the average diameter of surviving seedlings increased over time. Basal area (3 studies): Three site comparison studies (two also replicated, one also paired) in the USA compared mangrove forests created by planting propagules (along with other interventions) and mature natural forests. Two of the studies reported that planted forests had a smaller basal area than mature natural forests, after 7–18 years. The other study reported that planted forests had similar basal area to mature natural forests, after 17–30 years. OTHER            Germination/emergence (2 studies): One replicated study in the United Arab Emirates reported 65–92% germination of sown grey mangrove Avicennia marina seeds, across five coastal sites. One replicated study in a brackish/saline estuary in China reported 38–100% germination of planted mangrove propagules, depending on the species and habitat. Survival (16 studies): Fifteen studies quantified survival of individual tree/shrub propagules planted in brackish/saline wetlands (or plants originating from them). All 15 studies were of mangroves: in Central/South America, Asia, North America, Oceania or gloablly. All reported survival in at least some cases, from 20 days to 30 years after planting. Five studies reported 100% survival in some cases. However, nine studies reported 0% survival or absence of planted species in some cases. In five studies, survival of seeds or propagules was not distinguished from survival of planted seedlings. Proposed factors affecting survival rates included elevation/water levels, substrate, invertebrate herbivory, use of tree shelters, mechanical stress, oyster colonization, use of guidance, post-planting care and repeated planting. Growth (5 studies): Five studies monitored true growth of individual trees/shrubs (rather than changes in average height of survivors). All five studies (three replicated) in Australia, the USA, Colombia and the Philippines reported that mangrove seedlings, originating from planted seeds or propagules, grew over time. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3267https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3267Sat, 10 Apr 2021 15:36:07 +0100Collected Evidence: Collected Evidence: Limit vessel speeds Three studies evaluated the effects of limiting vessel speeds on reptiles. One study was in each of Australia, Costa Rica and the USA. COMMUNITY RESPONSE (0 STUDIES)   POPULATION RESPONSE (2 STUDIES) Survival (2 studies): One replicated, site comparison study in Costa Rica found that in waterways with enforced speed limits, fewer spectacled caiman were found dead with boat-related injuries compared to waterways with no speed limits. One replicated study in the USA found that vessels travelling at lower speeds caused fewer catastrophic injuries to artificial loggerhead turtle shells, though vessels with jet motors caused no catastrophic injuries at any speed tested. Condition (1 study): One replicated, site comparison study in Costa Rica found that in waterways with enforced speed limits, fewer spectacled caiman were found with boat-related injuries compared to waterways with no speed limits. BEHAVIOUR (1 STUDY) Behaviour change (1 study): One replicated study in Australia found that green turtles were more likely to flee from vessels travelling at lower speeds. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3531https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3531Tue, 07 Dec 2021 15:40:57 +0000Collected Evidence: Collected Evidence: Install exclusion devices on fishing gear: Sea turtles Three studies evaluated the effects of installing exclusion devices on fishing gear on sea turtle populations. One study was in the Gulf of Mexico (USA), one was in the Mid-Atlantic (USA) and one was off the coast of Western Australia. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Survival (1 study): One replicated, before-and-after study in the Gulf of Mexico found that when exclusion grids with escape holes were used in a shrimp trawl fishery there were fewer lethal strandings of loggerhead turtles compared to when grids were not used. BEHAVIOUR (1 STUDY) Use (1 study): One controlled study in the Mid-Atlantic found that when exclusion devices were used on scallop dredges there were fewer interactions with sea turtles than when no devices were used. OTHER (1 STUDY) Unwanted catch (1 study): One replicated study off the coast of Western Australia found that exclusion grids with escape hatches prevented sea turtles entering trawl nets. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3584https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3584Wed, 08 Dec 2021 15:30:20 +0000Collected Evidence: Collected Evidence: Install exclusion devices on fishing gear: Tortoises, terrapins, side-necked & softshell turtles Thirteen studies evaluated the effects of installing exclusion devices on fishing gear on tortoise, terrapin, side-necked & softshell turtle populations. Ten studies were in the USA, two were in Canada and one was in Australia. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Survival (1 study): One replicated, randomized, paired, controlled study in the USA found that fewer turtles died in hoop nets with an exclusion device than in unmodified traps. BEHAVIOUR (1 STUDY) Use (1 study): One randomized, controlled trial in the USA found mixed effects of crab pot exclusion devices on use of pots by diamondback terrapins depending on the device design. OTHER (13 STUDIES) Unwanted catch (13 studies): Eight of 13 controlled studies (including seven replicated, paired studies) in the USA, Australia and Canada found that crab pots, fyke nets, hoop nets and eel traps with exclusion devices caught fewer turtles, diamond back terrapins and short-necked turtles than unmodified gear. Two studies also found that modified gear caught smaller short-necked turtles and diamondback terrapins than unmodified gear. Three studies found mixed effects of exclusion devices on unwanted catch of turtles and diamondback terrapins depending on the device design. The other two studies found that that crab pots with wire exclusion devices or magnetized exclusion devices caught a similar number of diamondback terrapins compared to unmodified pots. One study also found that crab pots with wire exclusion devices caught larger diamondback terrapins than pots with plastic exclusion devices. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3590https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3590Wed, 08 Dec 2021 16:11:04 +0000Collected Evidence: Collected Evidence: Install exclusion devices on fishing gear: Snakes & lizards One study evaluated the effects of installing exclusion devices on fishing gear on snake and lizard populations. This study was in Australia. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Unwanted catch (1 study): One replicated study off the coast of Western Australia found that exclusion grids did not prevent sea snakes from entering trawl nets. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3599https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3599Wed, 08 Dec 2021 16:47:50 +0000Collected Evidence: Collected Evidence: Install escape devices on fishing gear: Sea turtles One study evaluated the effects of installing escape devices on fishing gear on sea turtle populations. This study was in the Gulf of Carpentaria (Australia). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Unwanted catch (1 Study): One randomized, paired, controlled study in the Gulf of Carpentaria found that trawl nets with escape devices caught a similar number of sea turtles compared to unmodified nets. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3601https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3601Wed, 08 Dec 2021 17:09:33 +0000Collected Evidence: Collected Evidence: Install escape devices on fishing gear: Snakes & lizards Three studies evaluated the effects of installing escape devices on fishing gear on snake and lizard populations. All three studies were in the Gulf of Carpentaria (Australia). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (3 STUDIES) Unwanted catch (3 Studies): One of two paired, controlled studies (including one randomized and one replicated study) in the Gulf of Carpentaria found that trawl nets with escape devices caught a similar number of sea snakes compared to unmodified nets. The other study found that trawl nets with an escape device caught fewer sea snakes compared to unmodified nets. One replicated, paired, controlled study in the Gulf of Carpentaria found that the placement of escape devices trawl nets affected the number of sea snakes caught compared to unmodified nets. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3603https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3603Thu, 09 Dec 2021 10:08:51 +0000Collected Evidence: Collected Evidence: Install exclusion and escape devices on fishing gear Six studies evaluated the effects of installing exclusion and escape devices on fishing gear on reptile populations. Two studies each were off the coast of Australia, in the Gulf of Carpentaria (Australia) and in the Adriatic Sea. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (2 STUDIES) Use (2 studies): Two replicated studies (including one controlled study) in the Adriatic Sea found that one or two loggerhead turtles were able to escape from a trawl net with an exclusion and escape device. OTHER (5 STUDIES) Unwanted catch (5 studies): Four studies (including two replicated, paired, controlled studies) off the coast of Australia and in the Gulf of Carpentaria (Australia) found that that trawl nets with an exclusion and escape device caught fewer loggerhead turtles or sea turtles and sea snakes compared to unmodified nets. One replicated study in the Adriatic Sea found that no loggerhead turtles were caught by a trawl net with an exclusion and escape device. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3605https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3605Thu, 09 Dec 2021 10:22:38 +0000Collected Evidence: Collected Evidence: Limit the number of fishing days One study examined the effects of limiting the number of fishing days on marine fish populations. The study was in the Mediterranean Sea (Italy). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): One before-and-after study in the Mediterranean Sea reported that in the 10 years following a decrease in overall number of days fished by a bottom trawl fleet, there was a higher biomass of thornback and brown rays. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3804https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3804Thu, 26 May 2022 14:24:22 +0100Collected Evidence: Collected Evidence: Limit fishing activity by vessel size and/or engine power One study examined the effects of limiting fishing activity by vessel size and/or engine power on marine fish populations. The study was in the North Sea (Northern Europe).   COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): One before-and-after study in the North Sea found that after vessels with a higher engine power were excluded from an area for half of each year there was a higher abundance of commercially targeted fish, but no difference in the overall abundance of non-commercially targeted fish over five years. In addition, for all fish, abundance was higher for two of eight size-groups. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3809https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3809Thu, 26 May 2022 14:53:03 +0100Collected Evidence: Collected Evidence: Introduce an overall catch limit (quota cap or total allowable catch) by fishery or fleet Nine studies examined the effects of introducing overall catch limits by fishery or fleet on marine fish populations. Three studies were worldwide, two studies were in the South Atlantic Ocean (Namibia/South Africa), two studies were in the North Sea (Northern Europe), and one study was in each of the North Sea and Atlantic Ocean (Scotland) and the North Atlantic Ocean (Canada).   COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (6 STUDIES) Abundance (5 studies): Four before-and-after studies (two replicated) in the South Atlantic Ocean, the North Atlantic Ocean and the North Sea reported that following the introduction of overall catch limits for fish there was a higher abundance or biomass of hakes, Atlantic herring and Atlantic halibut, compared to before. One replicated, controlled study of fish stocks worldwide found that overfished stocks of tunas and billfishes had faster increases of biomass when managed using overall catch limits, compared to stocks with other types of control or no management. Reproductive success (1 study): A global review reported that after overall catch limits and minimum landing size were introduced there was strong recruitment of broadbill swordfish for one key stock, while recruitment for four other stocks could not be assessed due to limited data. Survival (2 studies): One before-and-after study and one replicated, controlled study in the North Atlantic Ocean and worldwide found that for fish species with overall catch limits there was a decrease or lower fishing mortality, compared either to before implementation or to stocks without catch limits and those with other controls. BEHAVIOUR (0 STUDIES) OTHER (3 STUDIES) Reduction of unwanted catch (1 study): One replicated, before-and-after study in the North Sea and North Atlantic Ocean found that overall catch limits did not reduce unwanted megrim catch despite a reduction in discards, however this was due to retention of more small but legal-sized megrim, previously discarded. Reduction of fishing effort (1 study): One replicated, before-and-after study in the North Sea found that when annual total allowable catch limits were changed (increased or decreased), half of the otter trawl fleet had corresponding changes in fishing effort (increased or decreased), but there were no changes for the beam trawl fleet. Stock status (1 study): One global systematic review found that in terms of reaching biomass-based management targets fisheries with fleet-wide catch quotas were no different to fisheries managed either by catch shares or effort controls. However, along with catch share fisheries, fewer catch quota stocks were over-exploited than those with effort controls. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3811https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3811Thu, 26 May 2022 15:07:14 +0100Collected Evidence: Collected Evidence: Introduce catch shares Two studies examined the effects of introducing catch shares on marine fish populations. Both were reviews of fisheries worldwide.   COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Abundance (2 studies): One of two worldwide systematic reviews found that fisheries or stocks managed under catch shares were more likely to meet management target levels for biomass sustainability than those that did not meet targets. The other study found there was no difference in performance of biomass-based management targets between fisheries under catch shares, fleet-wide catch caps or fishing effort controls. BEHAVIOUR (0 STUDIES) OTHER (2 studies) Stock status (2 studies): Two worldwide systematic reviews found that catch share fisheries had lower rates of over-exploitation compared to non-catch share fisheries, and a higher proportion of fisheries managed under catch shares either met or exceeded management target levels for rates of exploitation than those that did not meet targets. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3812https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3812Fri, 27 May 2022 08:20:03 +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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