Collected Evidence: Collected Evidence: Use bait throwers to reduce seabird bycatchA study from Australia found significantly lower seabird bycatch on longlines set with a bait thrower.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F291https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F291Tue, 24 Jul 2012 16:50:50 +0100Collected Evidence: Collected Evidence: Use an alternative protein source: krill Two replicated studies in Norway found similar final weight gain between salmon that were fed diets containing fish meal only or a krill meal substitute. When the krill were de-shelled, growth rates were closer to salmon fed fish meal, compared to leaving the krill whole. Feed conversion ratios were found to be similar in both the fish meal and krill meal diets. The number of aerobic bacteria in the hindgut of salmon fed fish meal and krill meal were higher and composition of the bacterial flora was different.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F916https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F916Fri, 25 Oct 2013 13:04:28 +0100Collected Evidence: Collected Evidence: Use an alternative protein source: bacteria Evidence for the effects of replacing fish meal with bacterial protein is mixed. Two replicated, controlled studies in Norway found similar growth rates in salmon fed either a 100% fish meal (control) diet or experimental diets containing up to 25% bacterial protein to replace fish meal. In the diet containing 50% bacterial protein, growth rates were lower compared to the control. Another replicated, controlled study in Norway reported higher growth rates in salmon that were fed diets containing 18% and 36% bacterial protein compared to the control or a diet containing 4.5% bacterial protein.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F918https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F918Fri, 25 Oct 2013 13:10:39 +0100Collected Evidence: Collected Evidence: Use an alternative protein source: yeast One replicated, controlled experiment in Norway found no differences in weight between Atlantic salmon that were fed diets containing the yeast Yarrowia lipolytica compared to a control diet containing fishmeal.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F920https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F920Fri, 25 Oct 2013 13:13:26 +0100Collected Evidence: Collected Evidence: Use an alternative protein source: animal One controlled, replicated study in Canada found no difference in oxygen consumption or swimming speed of Atlantic salmon that were fed diets containing anchovy oil or alternative lipid sources. One controlled, randomised, replicated study from Scotland showed that fish fed a fishmeal diet weighed more than fish fed diets with alternative proteins.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F922https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F922Fri, 25 Oct 2013 13:16:53 +0100Collected Evidence: Collected Evidence: Use an alternative protein source: plant-based Six studies (four replicated, controlled) in Norway, Scotland and the USA found that inclusion of plant-based proteins within feed led to decreased growth rates in salmon. Three replicated and/or controlled studies from Norway, Canada and Scotland found similar growth rates in salmon fed either plant-based or fish meal diets. Four replicated, controlled studies (three randomised) from Norway and Scotland found reduced final body weights in salmon fed plant-based protein diets compared to fish meal-based diets. Two controlled studies (one replicated) from Norway found similar final body weights in salmon fed either plant-based or fish meal diets. Two replicated, controlled studies (one randomised) from Norway found lowered levels of feeding efficiency, whereas a replicated study in Norway found increased levels of feeding efficiency in salmon fed plant-based protein diets compared to fish meal diets. Two replicated studies (one controlled) in Canada and Scotland study found similar levels of feeding efficiency across both diet types. Digestibility of feed components by salmon was found to be lower in two replicated, controlled studies when the diets contained plant proteins compared to fish meal. Similar levels of digestibility across both diet types were identified by two randomised, replicated, controlled studies in Scotland and Norway. Two of the studies found that survival rates and appetite were not affected by plant- or fish meal-based protein diets. However morphology of the distal intestine was altered in two randomised, replicated, controlled studies where salmon were fed diets containing plant-based proteins. Condition of the salmon was increased in plant-based protein diets in one randomised, replicated, controlled study but reduced in two other replicated studies.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F924https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F924Fri, 25 Oct 2013 13:26:05 +0100Collected Evidence: Collected Evidence: Use an alternative oil source: plant-based Three replicated studies (two controlled) in Norway found growth rates were similar in salmon that were fed diets containing fish oil and vegetable oil. One replicated study in Norway found growth rates were higher in fish fed diets containing vegetable oil.  One replicated, controlled study found salmon growth rates were both lower and higher in vegetable oil diets compared to fish oil diets, dependant on family genetics. Two replicated studies (one controlled) in Norway found similar average final body weights between groups of salmon fed both fish oil and vegetable oil diets. Three studies (two replicated, one controlled) in Norway and Scotland found that the fatty acid profile of salmon flesh reflected oil source within diets. A study in Norway found that oil source in diets did not affect salmon broodstock fecundity levels, egg weights, fertility rates, as well as the weights and development of resultant fry. One replicated Norwegian study found that salmon fed vegetable oil diets had high liver lipid and low plasma lipoprotein compared to the fish oil diet. One replicated, controlled study found high levels of n-3 highly unsaturated fatty acids compared to diets containing rapeseed oil. A replicated, controlled study in Scotland found salmon fed vegetable oil-based diets had lower concentrations of dioxin and polychlorinated biphenyls within flesh, compared with diets containing fish oil. A replicated study in Norway found that fresh, frozen and smoked salmon flesh from fish fed vegetable oil- and fish oil-based diets had similar levels of gaping, texture and liquid holding capacity. Pigment concentration was lower in vegetable oil diets. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F926https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F926Fri, 25 Oct 2013 13:39:14 +0100Collected Evidence: Collected Evidence: Use exclusion nets A replicated, controlled trial in Australia found higher levels of sediment carbon at stocked cages with exclusion nets compared to cages without exclusion nets. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F945https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F945Mon, 28 Oct 2013 12:45:50 +0000Collected Evidence: Collected Evidence: Use an otter trawl instead of a dredge One study examined the effects of using an otter trawl instead of a dredge on subtidal benthic invertebrates. The study was in the Irish Sea (Isle of Man).   COMMUNITY RESPONSE (1 STUDY) Unwanted catch overall composition (1 study): One replicated, controlled, study in the Irish Sea found that an otter trawl caught a different species composition of unwanted invertebrate and fish species (combined) compared to two scallop dredges. POPULATION RESPONSE (1 STUDY) Overall abundance (1 study): One replicated, controlled, study in the Irish Sea found no difference in total invertebrate abundance and biomass living in or on the sediment of the trawl tracks following fishing with either an otter trawl or two scallop dredges. Unwanted catch overall abundance (1 study): One replicated, controlled, study in the Irish Sea found that an otter trawl caught fewer unwanted invertebrates and fish (combined) compared to two scallop dredges. OTHER (1 STUDY) Commercial catch abundance (1 study): One replicated, controlled, study in the Irish Sea found that an otter trawl caught similar number of commercially targeted queen scallops compared to two scallop dredges. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2123https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2123Tue, 22 Oct 2019 10:16:36 +0100Collected Evidence: Collected Evidence: Use an otter trawl instead of a beam trawl One study examined the effects of using an otter trawl instead of a beam trawl on subtidal benthic invertebrates. The study was in the North Sea (Germany and Netherlands).   COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Overall abundance (1 study): One replicated, paired, controlled study in the North Sea found that otter trawls caused similar mortality of invertebrates in the trawl tracks compared to beam trawls in sandy areas but lower mortality in silty areas. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2125https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2125Tue, 22 Oct 2019 10:19:09 +0100Collected Evidence: Collected Evidence: Use different bait species in traps One study examined the effects of using different bait species in traps on subtidal benthic invertebrates. The study took place in the South Pacific Ocean (New Zealand).   COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Unwanted catch abundance (1 study): One replicated, controlled study in the South Pacific Ocean found that the type of bait used in fishing pots did not change the amount of unwanted invertebrates caught. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2145https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2145Tue, 22 Oct 2019 11:16:22 +0100Collected Evidence: Collected Evidence: Use artificial light on fishing gear Two studies examined the effects of using artificial light on fishing gear on marine fish populations. One study was in the Pacific Ocean (USA) and one in the Barents Sea (Norway).  COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (2 STUDIES) Reduction of unwanted catch (1 study): One replicated, paired, controlled study in the Pacific Ocean found that shrimp trawl nets with artificial lights caught fewer unwanted fish when they were fitted to the fishing line, but not to a size-sorting grid, compared to a conventional trawl. Improved size-selectivity of fishing gear (1 study): One replicated, controlled study in the Barents Sea found that size-selectivity of long rough dab, Atlantic cod, haddock and redfish was not improved by the presence of LED lights on a size-sorting grid. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2695https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2695Wed, 02 Dec 2020 17:04:07 +0000Collected Evidence: Collected Evidence: Use an electric (pulse) trawl Three studies examined the effects of using an electric (pulse) trawl on marine fish populations. The studies were in the North Sea (Belgium, Netherlands and multiple European countries).  COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR RESPONSE (0 STUDIES) OTHER (3 STUDIES) Reduction of unwanted catch (3 studies): Two replicated, paired, controlled studies and one review in the North Sea found that using an electric/pulse trawl reduced the catches of non-target or undersized (discarded) commercial fish in some or all cases, compared to using a standard trawl. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2713https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2713Tue, 29 Dec 2020 16:45:07 +0000Collected Evidence: Collected Evidence: Use an alternative commercial fishing method Nine studies examined the effects of using an alternative commercial fishing method on marine fish populations. One study was in each of the Arafura Sea (Australia), the Greenland and Norwegian Seas (Norway), the Norwegian Sea (Norway), the Atlantic Ocean (Portugal), the Mediterranean Sea (Italy), the Gulf of Maine (USA), the Coral Sea (Australia), the Tyrrhenian Sea (Italy) and the Kattegat and Skagerrak (Sweden).  COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (9 STUDIES) Reduction of unwanted catch (9 studies): Seven of nine replicated studies (two controlled, one randomized, controlled, one paired, controlled) in the Arafura Sea, Greenland/Norwegian Sea, Norwegian Sea, Atlantic Ocean, Mediterranean Sea, Gulf of Maine, Coral Sea, Tyrrhenian Sea and Kattegat and Skagerrak found that using an alternative method of fishing caught fewer discarded fish species and reduced the catches of unwanted (discarded or non-commercial species) fish overall, and of immature halibut, haddock, Atlantic cod, bluefin tuna and over half of the individual fish species. One study found that an alternative fishing method caught larger (and more likely to be mature) unwanted hammerhead sharks. The other study found that sizes of striped sea bream, annular sea bream and red mullet were similar in catches between gear types. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2730https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2730Wed, 27 Jan 2021 17:06:17 +0000Collected Evidence: Collected Evidence: Use an alternative method to commercially harvest plankton One study examined the effect of using an alternative method to commercially harvest plankton on marine fish populations. The study was in the Norwegian Sea (Norway).  COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Reduction of unwanted catch (1 study): One controlled study in the Norwegian Sea found that the amount of unwanted fish larvae and eggs in fine-mesh catches of zooplankton were reduced after deployment of a bubble-plume harvester, compared to without deployment. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2731https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2731Thu, 28 Jan 2021 11:41:59 +0000Collected Evidence: Collected Evidence: Use acoustic devices at aquaculture systems Six studies evaluated the effects on marine and freshwater mammals of using acoustic devices at aquaculture systems. Four studies were in the North Atlantic Ocean (USA, UK), one was in the Reloncaví fjord (Chile) and one in the Mediterranean Sea (Italy). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (6 STUDIES) Human-wildlife conflict (6 studies): Four of six studies (including five before-and-after and/or site comparison studies and one controlled study) in the North Atlantic Ocean, the Reloncaví fjord and the Mediterranean Sea found that using acoustic devices at salmon farms reduced predation on caged salmon by grey seals, harbour seals and South American sea lions, or reduced the number of harbour seals approaching a fish cage. The two other studies found that using acoustic devices did not reduce harbour seal predation at salmon farms, or reduce the presence, approach distances, groups sizes or time spent around fin-fish farms by common bottlenose dolphins. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2775https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2775Thu, 04 Feb 2021 15:29:04 +0000Collected Evidence: Collected Evidence: Use acoustically reflective fishing gear materials Five studies evaluated the effects on marine mammals of using acoustically reflective fishing gear materials. Two studies were in the Bay of Fundy (Canada) and one study was in each of the Fortune Channel (Canada), the North Sea (Denmark) and the South Atlantic Ocean (Argentina). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (2 STUDIES) Behaviour change (2 studies): One controlled study in the Fortune Channel found that harbour porpoises approached nets made from acoustically reflective material (barium sulfate) and conventional nets to similar distances and for similar durations, but porpoises used fewer echolocation clicks at barium sulfate nets. One controlled study in the Bay of Fundy found that harbour porpoise echolocation activity was similar at barium sulfate and conventional nets. OTHER (3 STUDIES) Reduction in entanglements/unwanted catch (3 studies): Two of three controlled studies (including two replicated studies) in the North Sea, the Bay of Fundy and the South Atlantic Ocean found that fishing nets made from acoustically reflective materials (iron-oxide or barium sulfate) had fewer entanglements of harbour porpoises than conventional fishing nets. The other study found that nets made from barium sulfate did not reduce the number of dolphin entanglements. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2807https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2807Thu, 04 Feb 2021 17:31:28 +0000Collected Evidence: Collected Evidence: Use acoustic devices on fishing gear Thirty-three studies evaluated the effects on marine mammals of using acoustic devices on fishing gear. Eight studies were in the North Atlantic Ocean (Canada, USA, UK), four studies were in each of the North Pacific Ocean (USA) and the North Sea (Germany, Denmark, UK), three studies were in the Mediterranean Sea (Spain, Italy), two studies were in each of the Fortune Channel (Canada), the South Atlantic Ocean (Argentina, Brazil) and the Baltic Sea (Denmark, Germany, Sweden), and one study was in each of Moreton Bay (Australia), the Black Sea (Turkey), the Celtic Sea (UK), the South Pacific Ocean (Peru), the Rainbow Channel (Australia), the UK (water body not stated), the Great Belt (Denmark), Omura Bay (Japan), and the Indian Ocean (Australia). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (16 STUDIES) Behaviour change (16 studies): Twelve of 16 controlled studies (including three replicated studies) in the North Atlantic Ocean, the Fortune Channel, the South Atlantic Ocean, Moreton Bay, the Mediterranean Sea, the Celtic Sea, the Rainbow Channel, a coastal site in the UK, the Great Belt, the North Sea, Omura Bay and the Indian Ocean found that using acoustic devices on fishing nets, float lines or simulated fishing nets resulted in harbour porpoises, common bottlenose dolphins, tuxuci dolphins, finless porpoises and seals approaching nets or lines less closely, having fewer encounters or interactions with nets, or activity and sightings were reduced in the surrounding area. The other four studies found that using acoustic devices on trawl nets, float lines or simulated fishing nets did not have a significant effect on the behaviour of common bottlenose dolphins, harbour porpoises, Indo-Pacific humpback dolphins or dugongs. OTHER (19 STUDIES) Reduction in entanglements/unwanted catch (14 studies): Nine studies (including seven controlled studies and two before-and after studies) in the North Atlantic Ocean, the North Sea, the South Atlantic Ocean, the North Pacific Ocean, the Black Sea, and the South Pacific Ocean found that using acoustic devices on cod traps or fishing nets resulted in fewer collisions of humpback whales or entanglements of harbour porpoises, Franciscana dolphins, beaked whales and small cetaceans. Three studies (including two controlled studies and one before-and-after study) in the North Pacific Ocean found that using acoustic devices on fishing nets resulted in fewer entanglements of some species but not others. One controlled study in the North Atlantic Ocean found that fishing nets with a ‘complete’ set of acoustic devices had fewer entanglements of harbour porpoises, but those with an ‘incomplete’ set did not. One replicated, controlled study in the North Sea and Baltic Sea found that using acoustic devices on fishing nets reduced harbour porpoise entanglements in one fishing area but not the other. Human-wildlife conflict (6 studies): Five of six studies (including six controlled studies, one of which was replicated) in the Baltic Sea, the Mediterranean Sea, the North Pacific Ocean, a coastal site in the UK and the North Sea found that using acoustic devices reduced damage to fish catches and/or fishing nets caused by common bottlenose dolphins and seals. The other study found that acoustic devices did not reduce damage to swordfish catches by California sea lions. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2808https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2808Thu, 04 Feb 2021 17:56:14 +0000Collected Evidence: Collected Evidence: Use acoustic devices on fishing vessels Five studies evaluated the effects on marine mammals of using acoustic devices on vessels. One study was in each of the Shannon Estuary (Ireland), the Rainbow Channel (Australia), Keppel Bay (Australia), the North Atlantic Ocean (Azores) and the Indian Ocean (Crozet Islands). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (4 STUDIES) Behaviour change (4 studies): One controlled study in the Shannon Estuary found that common bottlenose dolphins avoided a boat more frequently when acoustic devices of two types were deployed alongside it. One controlled study in the Indian Ocean found that killer whales were recorded further from a fishing vessel when an acoustic device was used during hauls, but distances decreased after the first exposure to the device. Two before-and-after studies in the Rainbow Channel and Keppel Bay found that an acoustic device deployed alongside a vessel reduced surfacing and echolocation rates and time spent foraging or socializing of Indo-Pacific humpback dolphins and Australian snubfin dolphins but there was no effect on 8–10 other types of behaviour (e.g. vocalizing, diving, travelling etc.). OTHER (1 STUDY) Human-wildlife conflict (1 study): One randomized, controlled study in the North Atlantic Ocean found that using acoustic devices of two types did not reduce predation of squid catches by Risso’s dolphins. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2815https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2815Fri, 05 Feb 2021 14:45:12 +0000Collected Evidence: Collected Evidence: Use acoustic devices on moorings Eight studies evaluated the effects on marine and freshwater mammals of using acoustic devices on moorings. Two studies were in the South Pacific Ocean and one study was in each of the Puntledge River (Canada), the Bay of Fundy (Canada), the Shannon Estuary (Ireland), the Rivers Conon and Esk (UK), the Kyle of Sutherland estuary (UK) and the North Atlantic Ocean (UK). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (7 STUDIES) Behaviour change (7 studies): Two of four controlled studies in the South Pacific Ocean, the Kyle of Sutherland estuary and the North Atlantic Ocean found that deploying acoustic devices on moorings reduced numbers of grey and harbour seals, and the activity of harbour porpoises, short-beaked common dolphins and common bottlenose dolphins. The two other studies found that using an acoustic device on a mooring did not have a significant effect on the number, direction of movement, speed, or dive durations of migrating humpback whales. One controlled study in the Bay of Fundy found that using an acoustic device on a mooring reduced harbour porpoise echolocation activity, but the probability of porpoises approaching within 125 m of the device increased over 10–11 days. One controlled study in the Shannon Estuary found that one of two types of acoustic device reduced the activity of common bottlenose dolphins. One replicated, controlled study in the Rivers Conon and Esk found that using acoustic devices reduced the number of grey and harbour seals upstream of the device but did not reduce seal numbers overall. OTHER (1 STUDY) Human-wildlife conflict (1 study): One randomized controlled study in the Puntledge River found that deploying an acoustic device on a mooring reduced the number of harbour seals feeding on migrating juvenile salmon. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2816https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2816Fri, 05 Feb 2021 15:00:49 +0000Collected Evidence: Collected Evidence: Use catch and hook protection devices on fishing gear Five studies evaluated the effects on marine mammals of using catch and hook protection devices on fishing gear. Two studies were in the South Pacific Ocean (Chile, Australia and Fiji), two were in the Indian Ocean (Seychelles, Madagascar) and one was in the Southwest Atlantic Ocean. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (5 STUDIES) Reduction in entanglements/unwanted catch (1 study): One study in the South Pacific Ocean found that using cage or chain devices on fishing hooks resulted in fewer unwanted catches of toothed whales. Human-wildlife conflict (5 studies): Two of four studies (including three controlled and one before-and-after study) in the South Pacific Ocean, the Southwest Atlantic Ocean and the Indian Ocean found that net sleeves or cage and chain devices on fishing hooks reduced damage to fish catches by sperm whales, killer whales and toothed whales. The two other studies found that attaching ‘umbrella’ or ‘spider’ devices on fishing hooks did not reduce predation and/or damage to fish catches by sperm whales or toothed whales. One controlled study in the Indian Ocean found that attaching catch protection devices made from streamers to fishing lines reduced Indo-Pacific bottlenose and spinner dolphin predation on fish bait, but only during the first two trials. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2821https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2821Fri, 05 Feb 2021 15:18:24 +0000Collected Evidence: Collected Evidence: Use baited lines instead of nets for shark control Two studies evaluated the effects on marine mammals of using baited lines instead of nets for shark control. One study was in the Indian Ocean (South Africa) and one in the South Pacific Ocean (Australia). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Survival (1 study): One site comparison study in the South Pacific Ocean found that using baited lines instead of nets increased the survival of entangled common and bottlenose dolphins. BEHAVIOUR (0 STUDIES) OTHER (2 STUDIES) Reduction in entanglements/unwanted catch (2 studies): Two site comparison studies in the Indian Ocean and South Pacific Ocean found that baited lines used for shark control had fewer entanglements of dolphins, whales and dugongs than nets. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2856https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2856Mon, 08 Feb 2021 11:13:28 +0000Collected Evidence: Collected Evidence: Use acoustic devices to deter marine and freshwater mammals from an area to reduce noise exposure Four studies evaluated the effects of using acoustic devices to deter marine and freshwater mammals from an area to reduce noise exposure. Two studies were in the North Sea (Germany), one study was in the Great Belt (Denmark) and one was in Faxaflói Bay (Iceland). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (4 STUDIES) Behaviour change (4 studies): Three studies (including two controlled and one before-and-after study) in the North Sea and the Great Belt found that using acoustic devices to deter mammals from an area at a wind farm construction site or pelagic sites reduced the activity and sightings of harbour porpoises at distances of 1–18 km from the devices. One before-and-after study in Faxaflói Bay found that when an acoustic device was deployed from a boat, minke whales swam away from the device, increased their swimming speed, and swam more directly. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2896https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2896Mon, 08 Feb 2021 12:04:42 +0000Collected Evidence: Collected Evidence: Use circle hooks instead of J-hooks Eleven studies evaluated the effects of using circle hooks instead of J-hooks on reptile populations. Five studies were in the Atlantic, three were in the Pacific and one study was in each of the Mediterranean, the Atlantic and North Pacific and the western North Atlantic, Azores, Gulf of Mexico and Ecuador. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (3 STUDIES) Survival (3 studies): Two studies (including one replicated, controlled, paired study) off the coast of Hawaii and in the north-east Atlantic Ocean found that survival of loggerhead and leatherback turtles and leatherback and hard-shell sea turtles caught by circle hooks or J-hooks was similar. One review of studies in five pelagic longline fisheries found that fewer sea turtles died when circle hooks were used compared to J-hooks in four of five fisheries. Condition (3 studies): Two replicated, controlled studies in the Mediterranean Sea and south-western Atlantic Ocean found that fewer immature loggerhead turtles and loggerhead turtles swallowed circle hooks compared to J-hooks. One before-and-after study off the coast of Hawaii found that a lower percentage of loggerhead and leatherback turtles were deeply hooked by circle hooks compared to J-hooks. BEHAVIOUR (0 STUDIES) OTHER (11 STUDIES) Unwanted catch (11 studies): Seven of 10 studies (including six replicated, controlled studies) in the Pacific, Atlantic, Atlantic and North Pacific and Mediterranean and one review of studies in five pelagic longline fisheries found that circle hooks or circle hooks and tuna hooks caught fewer sea turtles than J-hooks, or that non-offset G-style circle hooks caught fewer leatherback and hard-shell sea turtles that offset J-Hooks. One of these studies also found that circle hooks caught slightly larger loggerhead turtles than J-hooks, and one also found that offset Gt-style circle hooks caught a similar number of leatherback and hard-shell sea turtles compared to offset J-hooks. One study found that circle hooks caught a similar number of leatherback, green and olive ridley turtles compared to J-hooks. One study found that fish-baited circle hooks caught fewer loggerhead and leatherback turtles than squid-baited J-hooks. The review found mixed effects of using circle hooks compared to J-hooks on unwanted catch of sea turtles depending on the fishery. The other study found mixed effects of using circle hooks or J-hooks in combination with squid or fish bait on the number of loggerhead and leatherback turtles that were caught. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3559https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3559Wed, 08 Dec 2021 14:21:43 +0000Collected Evidence: Collected Evidence: Use dyed bait Two studies evaluated the effects of using dyed bait on reptile populations. One study was in Costa Rica and one was in the North Pacific. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (1 STUDY) Use (1 study): One randomized, paired, controlled study in Costa Rica found that loggerhead and Kemp’s ridley turtles showed mixed preferences for dyed compared to non-dyed bait in captive trials. OTHER (2 STUDIES) Unwanted catch (2 studies): Two paired studies (including one randomized, controlled study) in Costa Rica and the North Pacific found that hooks with dyed bait caught a similar number of olive ridley and green turtles and loggerhead turtles compared to hooks with non-dyed bait. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3611https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3611Thu, 09 Dec 2021 10:46:51 +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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Our blog contains the latest news and updates from the Conservation Evidence team, the Conservation Evidence Journal, and our global partners in evidence-based conservation.

Who uses Conservation Evidence?

Meet some of the evidence champions

Endangered Landscape ProgrammeRed List Champion - Arc Kent Wildlife Trust The Rufford Foundation Save the Frogs - Ghana Mauritian Wildlife Supporting Conservation Leaders
Sustainability Dashboard National Biodiversity Network Frog Life The international journey of Conservation - Oryx Cool Farm Alliance UNEP AWFA Bat Conservation InternationalPeople trust for endangered species Vincet Wildlife Trust
For a full list of, and information about, our champions:
All Evidence Champions
About our champions, why and how to become one:
Become an Evidence Champion

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