Collected Evidence: Collected Evidence: Raise awareness amongst the general public through campaigns and public informationA review of programmes in the USA and Canada argues that education was not sufficient to change behaviour, although it was necessary as a catalytic factor for economic incentives and law enforcement.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F162https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F162Sat, 19 May 2012 19:59:49 +0100Collected Evidence: Collected Evidence: Protect bird nests using electric fencing One before-and-after study from the UK found an increase in tern numbers after the erection of an electric fence, whilst a study from the USA found an increase in the number of nests. Five studies from the USA found higher survival or productivity at wader or seabird colonies with electric fencing, compared to areas without fencing, although one study found that hatching rates were no different, whilst nesting success was only higher in one of two years. One study from the USA found lower predation by mammalian predators inside electric fence exclosures, whilst predation by birds was higher. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F188https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F188Wed, 13 Jun 2012 16:59:40 +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: Use nest covers to reduce the impact of research on predation of ground-nesting seabirdsA before-and-after study in Canada found that protecting Caspian tern Sterna caspia nests after researchers disturbed parents from them significantly increased hatching success. This was due to a reduction in predation by ring-billed gulls Larus delawarensis.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F316https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F316Wed, 25 Jul 2012 18:26:31 +0100Collected Evidence: Collected Evidence: Restore or create shrubland Only one of the four studies captured investigated the effects of shrubland restoration in isolation. This small before-and-after study from the UK found that one or two pairs of northern lapwing bred on an area of restored moorland, whereas none had previously bred in the area. A study from the USA and one from the Azores found that populations of target species (gamebirds and seabirds) increased following shrubland restoration, amongst other interventions. A replicated study from the UK which did not distinguish between several interventions performed found a negative relationship between the combined intervention and the ratio of young-to-old grey partridges.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F364https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F364Mon, 06 Aug 2012 13:03:08 +0100Collected Evidence: Collected Evidence: Control avian predators on islands Out of 10 studies, six before-and-after studies from North America, Australia and Europe found that controlling avian predators led to increased population sizes, reduced mortality or increased reproductive success in seabirds on islands. The North American studies had several interventions, so increases could not be linked directly to predator control, and one found that increases were only at one of two sites studied. Two controlled studies in Europe found little evidence that crow control led to increased reproductive success in gamebirds or raptors on islands. A North American study found that, despite higher reproductive success, very few birds returned to the study site after predator removal. A study from North America found that an Atlantic puffin Fratercula arctica translocation programme, combined with the culling of predatory gulls, appeared to be successful. A study from the UK found that the number of common terns Sterna hirundo and black-headed gulls Larus ridibundus declined on gravel islands despite the attempted control of large gulls.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F372https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F372Tue, 07 Aug 2012 14:43:03 +0100Collected Evidence: Collected Evidence: Control mammalian predators on islandsThe assessment of the effectiveness of this intervention was based on a total of 33 studies across all species groups. See Background section below for links to the evidence for the control of mammalian predators on islands on specific species groups. A paired sites study from Finland and a literature review from the UK found increased bird species richness and abundance or population recoveries and recolonisations, following the control or eradication of mammalian predators. Predators removed included American mink Mustela vison, rats Rattus spp. pigs Sus scrofa, cats Felis catus, dogs Canis familiaris and grey fox Dusicyon griseus.    Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F373https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F373Tue, 07 Aug 2012 15:31:12 +0100Collected Evidence: Collected Evidence: Control mammalian predators on islands for seabirds We found 16 before-and-after studies, one paired sites study and one literature review from around the world, all describing positive seabird responses to the removal or control of mammalian predators (mainly rats Rattus spp. and feral cats Felis catus) from islands. Of these 18 studies, seven found either large population increases or recolonisations following predator eradication or control. Two of these found only partial population increases or recolonisations: a study from Alaska. Twelve studies found increases in reproductive success and survival or decreases in predation and mortality following predator control. In one case there was also a small population increase. Rats and mice Mus musculus were controlled in twelve studies, mostly examining burrow-nesting seabirds; cats in eight, mostly on ground or cliff-nesting seabirds; and other species in two.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F375https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F375Tue, 07 Aug 2012 15:57:05 +0100Collected Evidence: Collected Evidence: Control predators not on islands for seabirds A before-and-after study from New Zealand found an increase in a tern population following intensive trapping of invasive mammals. A before-and-after study from Canada found increases in tern fledging success following gull control.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F385https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F385Wed, 08 Aug 2012 16:42:50 +0100Collected Evidence: Collected Evidence: Turn off lights to reduce mortality from artificial lightsA before-and-after study from the UK found that fewer seabirds (Manx shearwaters Puffinus puffinus, European storm petrels Hydrobates pelagicus and Leach’s storm petrels Oceanodroma leucorhoa) were attracted to artificial lighting and downed when lighting was reduced at night, compared to when normal lighting was in place.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F467https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F467Wed, 29 Aug 2012 16:24:50 +0100Collected Evidence: Collected Evidence: Provide artificial nesting sites for ground and tree-nesting seabirds Three studies from the UK and the Azores found increases in gull and tern populations following the provision of rafts/islands or providing nest boxes alongside other interventions. A controlled, replicated study from the USA found that terns had higher nesting success on nesting rafts in one of two years monitored and a before-and-after study from Japan found that nesting success increased after the provision of nesting substrate. Five studies from Canada and Europe found that terns used re-profiled or artificial islands or nesting rafts, but pelicans did not. A small study from Hawaii found that red-footed boobies Sula sula preferentially nested in an artificial ‘tree-style’ nesting structure, compared to other designs.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F480https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F480Thu, 30 Aug 2012 14:40:27 +0100Collected Evidence: Collected Evidence: Artificially incubate and hand-rear seabirds in captivity Five studies from across the world found evidence for the success of hand-rearing seabirds. One small study in Spain found that one of five hand-reared Audouin’s gulls Larus audouinii successfully bred in the wild. Four studies found that various petrel species (Procellariiformes) successfully fledged after hand-rearing. One controlled study found that fledging rates of hand-reared birds was similar to parent-reared birds, although a study on a single bird found that the chick fledged at a lower weight and later than parent-reared chicks.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F604https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F604Sat, 13 Oct 2012 16:50:42 +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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