Conservation Evidence: Evidence Data

Collected Evidence: Collected Evidence: Scare birds from fish farms One before-and-after study from Israel found that the population of pygmy cormorants in the area increased after birds were scared away from fish farms, possibly due to lower persecution. One of two studies that examined fish stocks found that fewer fish were taken from a farm when heron distress calls were played. The other study, a literature review, found no evidence for the effects of scaring birds on fish stocks. Two replicated studies from Belgium and Australia found that using foot patrols to disturb birds from fish farms did not reduce the number of birds present or fish consumption. Ten of eleven studies from across the world, three controlled, found evidence that playing distress calls or using other acoustic deterrents (some with flashes of light) reduced the number of birds at fish farms, or changed bird behaviours. One of these involved underwater broadcasting. One study found effects were only temporary and five found that birds became habituated to noises. Four studies, one replicated and controlled, two before-and-after, found that acoustic deterrents were not effective in scaring birds. Five of seven studies, one controlled, found evidence that visual deterrents (including inflatable ‘Scarey Man’ scarecrows) reduced the number of birds at fish farms. Three found evidence for habituation to deterrents and three studies found no evidence that visual deterrents were effective. Two studies examined other deterrents, finding that trained raptors were effective but that the effects of helicopters and ultra-light aircraft were either inconclusive or very temporary. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F244https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F244Wed, 18 Jul 2012 11:00:04 +0100Collected Evidence: Collected Evidence: Set longlines at night to reduce seabird bycatch Six out of eight studies from fisheries around the world found lower rates of seabird bycatch on longlines set at night, compared with during the day, or with previously collected data. However, effects seemed to depend on the species caught. Two studies found higher rates of bycatch on night-set longlines, due to high numbers of white-chinned petrels Procellaria aequinoctialis or northern fulmars Fulmarus glacialis being caught at night. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F283https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F283Tue, 24 Jul 2012 13:04:04 +0100Collected Evidence: Collected Evidence: Turn deck lights off during night-time setting of longlines to reduce bycatchA single replicated and controlled study in the South Atlantic found significantly lower bycatch rates when deck lights were turned off during line setting at night. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F284https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F284Tue, 24 Jul 2012 14:11:52 +0100Collected Evidence: Collected Evidence: Use streamer lines to reduce seabird bycatch on longlines A total of eight studies and two literature reviews from coastal and pelagic fisheries across the world found strong evidence for reduced seabird bycatch on longlines when streamer lines were used. A replicated, controlled trial from the sub-Antarctic Indian Ocean found no reduction in bycatch rates when using streamer lines, whilst five studies were inconclusive, uncontrolled or had weak evidence for reductions. The effect of streamer lines appears to vary between seabird species: northern fulmars Fulmarus glacialis were consistently caught at lower rates when streamers were used but shearwaters Puffinus spp. and white-chinned petrels Procellaria aequinoctialis were caught at similar rates with and without streamers in one study each. The three studies that investigated the use of multiple streamer lines all found that fewer birds were caught when two streamer lines were used, compared to one, with even fewer caught when three were used. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F285https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F285Tue, 24 Jul 2012 14:37:19 +0100Collected Evidence: Collected Evidence: Set lines underwater to reduce seabird bycatch Four replicated and controlled studies and a literature review in Norway, South Africa and the North Pacific found reductions in northern fulmar Fulmarus glacialis, albatross and petrel bycatch rates when using an underwater setting funnel. Although one found a disproportionate number of albatross were caught during day line setting. A replicated and controlled study found that underwater setting increased attack rates of shearwaters Puffinus spp. on longlines and did not reduce bycatch. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F288https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F288Tue, 24 Jul 2012 16:38:44 +0100Collected Evidence: Collected Evidence: Use a line shooter to reduce seabird bycatch A randomised, replicated and controlled trial from a pelagic fishery in the North Pacific found significantly higher seabird bycatch when a line shooter was used to set longlines. A second randomised, replicated and controlled trial (from Norway), found no effect of a line shooter on bycatch rates. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F290https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F290Tue, 24 Jul 2012 16:47:45 +0100Collected 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: Dye baits to reduce seabird bycatchA randomised replicated and controlled study in Hawaii found that dying bait blue significantly reduced the number of attacks from albatross on baits being set. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F293https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F293Tue, 24 Jul 2012 16:57:28 +0100Collected Evidence: Collected Evidence: Weight baits or lines to reduce longline bycatch of seabirds Three replicated and controlled studies found evidence for reduced bycatch in some species when using weighted lines. One study found low bycatch rates, but was uncontrolled. In Hawaii and New Zealand, rates of bait loss and bycatch of albatrosses Phoebastria spp., white-chinned petrels Procellaria aequinoctialis and sooty shearwaters Puffinus griseus were much lower with weighted baits or integrated weight lines than with control lines. In the North Pacific, two trials found that bycatch rates of some species was reduced when using weights, but that shearwaters Puffinus spp. attacked weighted lines more often. A study off New Zealand found that attaching weights to lines had only localised effects on sink-rate. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F296https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F296Tue, 24 Jul 2012 17:07:29 +0100Collected Evidence: Collected Evidence: Use shark liver oil to reduce seabird bycatch Two replicated and controlled trials found reductions in the number of seabirds following boats, or diving for baits, when shark liver oil was dripped behind the boats. Other oils had no effect. A third replicated and controlled trial in found no differences in the number of seabirds following a bait-laying boat with shark liver oil. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F297https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F297Tue, 24 Jul 2012 17:16:47 +0100Collected Evidence: Collected Evidence: Thaw bait before setting lines to reduce seabird bycatchA single study from Australia found that lines set using thawed baits caught significantly fewer seabirds than controls. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F298https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F298Tue, 24 Jul 2012 17:24:13 +0100Collected Evidence: Collected Evidence: Reduce seabird bycatch by releasing offal overboard when setting longlinesTwo replicated and controlled studies in the South Atlantic and sub-Antarctic Indian Ocean found significant reductions in the number of albatross and petrels attacking baits and being caught when offal was released overboard during line setting. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F299https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F299Tue, 24 Jul 2012 17:39:55 +0100Collected Evidence: Collected Evidence: Use acoustic alerts on gillnets to reduce seabird bycatchA repeated, randomised and controlled trial in the USA found that sonic alerts reduced the number of common guillemots Uria aalge but not rhinoceros auklets Cerorhinca monocerata caught in gillnets. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F301https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F301Tue, 24 Jul 2012 18:02:45 +0100Collected Evidence: Collected Evidence: Use high-visibility mesh on gillnets to reduce seabird bycatch A repeated, randomised and controlled trial in the USA found that having gillnets made partially from high-visibility mesh was effective in reducing seabird bycatch. Having a greater percentage (25% vs. 10%) of the net made from high-visibility mesh was more effective, but also reduced catch of the target species. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F303https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F303Tue, 24 Jul 2012 18:10:09 +0100Collected 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: Habituate birds to human visitorsA replicated, controlled study from Australia found that bridled terns Sterna anaethetus in heavily disturbed had similar or higher reproductive success compared with less-disturbed sites, possibly suggesting that habituation had occurred. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F315https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F315Wed, 25 Jul 2012 18:18:05 +0100Collected Evidence: Collected Evidence: Clean birds following oil spills Three studies from South Africa and Australia found high survival of rehabilitated penguins and plovers or similar survival to un-oiled birds. However a large study from the USA and Canada found that rehabilitated common guillemots Uria aalge had significantly lower survival than untreated birds. Three studies from South Africa and Australia found that rehabilitated birds bred, with one finding that rehabilitated birds had similar breeding success to un-oiled birds. However, this study found that birds rehabilitated after a second spill were less likely to breed, whilst two other studies found that rehabilitated birds had lower success than un-oiled birds. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F448https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F448Thu, 23 Aug 2012 16:12:49 +0100Collected Evidence: Collected Evidence: Use visual and acoustic ‘scarers’ to deter birds from landing on pools polluted by mining or sewage Two studies found lower bird mortality or fewer birds rescued from toxic ponds when deterrent systems were used. Four of five studies found that fewer birds landed on pools with deterrents than controls, although one of these found that the effect was weaker for grebes compared to wildfowl and absent for waders. One study that used regular broadcasts of different sounds found that it had no impact on bird behaviour. Two studies investigated different systems and found that radar-operated systems were more effective than systems that worked at random intervals. One of these studies also found that loud noises were more effective than moving peregrine falcons Falco peregrinus models. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F452https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F452Wed, 29 Aug 2012 13:32:11 +0100Collected Evidence: Collected Evidence: Use lights low in spectral red to reduce mortality from artificial lightsTwo studies from the North Sea and the Netherlands found that fewer birds were attracted to low-red lights (including green and blue lights), compared with the number expected, or the number attracted to white or red lights. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F471https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F471Wed, 29 Aug 2012 16:40:31 +0100Collected Evidence: Collected Evidence: Use of probiotics and immunostimulants One replicated study in Scotland found increased survival in salmon fed a probiotic before exposure to four different disease-causing bacteria over a 28 day period compared with controls. A replicated, controlled study in Norway found the number of salmon infected with lice was reduced by 28% when fed a diet composed of fish meal and 28% plant-based protein. Adding beta-glucans to the diet decreased lice infection levels by a further 28% compared with controls. The same study found the addition of mannan oligosaccharides improved gut function by preventing the development of soybean-induced enteritis compared with controls. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F732https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F732Mon, 03 Jun 2013 11:14:24 +0100Collected Evidence: Collected Evidence: Use vaccinations Two controlled studies from Iceland and Norway found higher survival rates in vaccinated salmon compared to unvaccinated control groups. This was post exposure to the disease-causing bacteria, Aeromonas salmonicida spp.achromogenes and Yersinia ruckeri, respectively. Two controlled studies in Australia and Canadia reported higher survival in salmon infected with marine flexibacteriosis and bacterial kidney disease, post vaccination. Two controlled studies in Norway reported similar results for salmon vaccinated against infectious salmon anaemia. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F733https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F733Mon, 03 Jun 2013 14:33:01 +0100Collected 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: Use natural control agents: cleaner wrasse Two studies in Ireland found mixed effects of cleaner wrasse on sea lice numbers infesting salmon. One controlled study found corkwing and goldskinny cleaner wrasse were as effective at controlling lice infestation as chemical treatments. One replicated, controlled study found rockcook cleaner wrasse were ineffective at preventing lice outbreaks. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F738https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F738Mon, 03 Jun 2013 15:28:00 +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: Reduce fish meal in diet Two replicated studies in Norway found similar final weights in salmon that were fed diets containing low, medium or high levels of fish meal. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F915https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F915Fri, 25 Oct 2013 12:26:12 +0100