Collected Evidence: Collected Evidence: Set longlines at the side of the boat to reduce seabird bycatch We found no evidence for the effects on seabird bycatch rates of setting longlines from the side of the boat. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F289https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F289Tue, 24 Jul 2012 16:44:03 +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: Tow buoys behind longlining boats to reduce seabird bycatch We found no evidence for the effects on seabird bycatch rates of towing buoys behind longlining boats. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F292https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F292Tue, 24 Jul 2012 16:54:34 +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: Use high-visibility longlines to reduce seabird bycatch We captured no intervention-based evidence on the impact on seabird bycatch of high-visibility longlines. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.    Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F294https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F294Tue, 24 Jul 2012 16:58:27 +0100Collected Evidence: Collected Evidence: Use a sonic scarer when setting longlines to reduce seabird bycatchA single study from the South Atlantic found that seabird bycatch rates did not appear to be lower on longlines set with a sonic scarer, and that changes in seabird behaviour due to the scarer were only temporary.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F295https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F295Tue, 24 Jul 2012 16:59:51 +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 bird exclusion devices (BEDs) such as ‘Brickle curtains’ to reduce seabird mortality when hauling longlinesA study of longliners in the South Atlantic found that fewer seabirds were caught on longlines hauled under BEDs with two booms, compared to those with a single boom.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F302https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F302Tue, 24 Jul 2012 18:03:33 +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: Reduce gillnet deployment time to reduce seabird bycatch We found no evidence for the effects on seabird bycatch rates of reducing gill net deployment time. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.    Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F304https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F304Tue, 24 Jul 2012 18:11:14 +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: Reduce ‘ghost fishing’ by lost/discarded gear We found no evidence for the effects on seabird bycatch rates or populations of reducing ghost fishing. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.    Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F306https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F306Tue, 24 Jul 2012 18:18:01 +0100Collected Evidence: Collected Evidence: Reduce bycatch by employing seasonal or area closures We found no evidence for the effects on seabird populations or bycatch rates of seasonal or area closures. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.    Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F307https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F307Tue, 24 Jul 2012 18:19:08 +0100Collected Evidence: Collected Evidence: Use signs and access restrictions to reduce disturbance at nest sites Six studies (two replicated and controlled, two before-and-after and two small studies) from across the world found increased numbers of breeders, higher reproductive success or lower levels of disturbance in waders and terns following the start of access restrictions or the erection of signs near nesting areas. One Canadian study involved the use of multiple interventions. A before-and-after study from the USA found that a colony of black-crowned night herons Nycticorax nycticorax was successfully relocated to an area with no public access. One small study from Europe and one replicated and controlled study from Antarctica found no effect of access restrictions on the reproductive success of eagles or penguins, respectively.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F309https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F309Wed, 25 Jul 2012 16:56:43 +0100Collected Evidence: Collected Evidence: Set minimum distances for approaching birds (buffer zones) We captured no evidence for the effects on bird populations of setting minimum distances for approaching birds. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.    Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F310https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F310Wed, 25 Jul 2012 17:15:32 +0100Collected Evidence: Collected Evidence: Provide paths to limit the extent of disturbanceA before-and-after study from the UK found that two species of wader nested closer to a path, or at higher densities near the path, following resurfacing, which resulted in far fewer people leaving the path.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F311https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F311Wed, 25 Jul 2012 17:34:15 +0100Collected Evidence: Collected Evidence: Reduce visitor group size We found no intervention-based studies examining the effects of reducing visitor numbers on bird populations. However, a single, replicated study in forests in Spain in 2004 (Remacha et al. 2011) found that fewer birds, but not fewer species, were observed as visitor number increased. This effect was largely due to decreases in collared dove Streptopelia decaocto presence and serin Serinus serinus abundance. Remacha, C., Perez-Tris, J. & Antonio Delgado, J. (2011) Reducing visitors’ group size increases the number of birds during educational activities: Implications for management of nature-based recreation,Journal of Environmental Management, 92, 1564–1568. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.      Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F312https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F312Wed, 25 Jul 2012 17:36:40 +0100Collected Evidence: Collected Evidence: Use voluntary agreements with local people to reduce disturbanceA before-and-after trial in the USA found significantly lower disturbance rates following the establishment of a voluntary waterfowl avoidance area (VWAA), despite an overall increase in boat traffic.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F313https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F313Wed, 25 Jul 2012 18:06:42 +0100Collected Evidence: Collected Evidence: Start educational programmes for personal watercraft ownersA before-and-after trial in the USA found that rates of disturbance by personal watercraft decreased and reproductive success of common terns Sterna hirundo increased following a series of educational programmes aimed at recreational boat users.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F314https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F314Wed, 25 Jul 2012 18:11:40 +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 +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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