Collected Evidence: Collected Evidence: Use repellents on baits for predator control A replicated, randomised and controlled experiment in the USA found that methyl anthanilate and aminoacetophenone did not reduce consumption of baits by American kestrels Falco sparverius. A replicated, randomised and controlled experiment in New Zealand found that treating baits with pulegone or Avex™ reduced pecking rates in North Island robins Petroica australis longipes. Collected, 15 May 2012 13:51:05 +0100Collected Evidence: Collected Evidence: Use traditional breeds of livestockA replicated controlled study in four European countries found no differences in bird abundances between areas grazed with traditional or commercial breeds of livestock.  Collected, 17 Jul 2012 15:53:48 +0100Collected Evidence: Collected Evidence: Use raptor models to deter birds and so reduce incidental mortalityA single paired sites study in Spain found no evidence that raptor models were effective in deterring birds from crossing power lines and may even have attracted some species to the area.  Collected, 19 Jul 2012 14:53:56 +0100Collected Evidence: Collected Evidence: Use wildlife refuges to reduce hunting disturbance Three studies from the USA and Europe found that bird densities were higher in refuges where hunting was prohibited, compared to areas with hunting. In addition, two studies found that more birds used hunting-free areas during the open season and on hunting days. No studies investigated the population-level impacts of these refuges.  Collected, 24 Jul 2012 12:34:46 +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, 24 Jul 2012 14:37:19 +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, 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, 24 Jul 2012 17:16:47 +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, 25 Jul 2012 16:56:43 +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, 25 Jul 2012 18:06:42 +0100Collected Evidence: Collected Evidence: Use prescribed burning on shrublands One controlled study from the USA, of eight captured, found that overall bird densities were similar between burned and unburned areas, whilst a replicated and controlled study found that species numbers and bird densities did not vary between areas burned in summer and those burned in winter. Three studies found that some species were more abundant on areas that were burned, compared to those managed differently, or not at all. Four studies found that the densities of individual species were similar or lower on burned areas compared to control areas or those under different management. A before-and-after study found that sage sparrows chose different nest sites before burning compared to after. A controlled study found no differences in greater sage grouse movement between burned and unburned areas.  Collected, 26 Jul 2012 15:10:30 +0100Collected Evidence: Collected Evidence: Use selective harvesting/logging instead of clearcutting Six studies of seven from the USA and Canada found that some species were more abundant in selective-logged forests, whilst others were less abundant, compared to both control stands and other managements. One study found that there were no consistent differences between selectively harvested and clearcut stands. A replicated study from the USA found a lower species richness of cavity-nesting birds in snags in selectively-logged stands, compared to clearcuts. A replicated study from the USA found that brood parasitism of two species by brown-headed cowbirds was higher in harvested stands compared to controls, but it was lower for two others.  Collected, 28 Jul 2012 13:49:15 +0100Collected Evidence: Collected Evidence: Use variable retention management during forestry operationsA replicated, controlled study from the USA found that nine bird species occurred at higher densities in stands under variable retention management, compared to control stands. Five were found at lower densities.  Collected, 28 Jul 2012 14:02:54 +0100Collected Evidence: Collected Evidence: Use shelterwood cutting instead of clearcuttingA replicated study from the USA found that community composition of birds in shelterwood stands differed from other forestry practices, with some species more abundant and others less so.  Collected, 28 Jul 2012 14:08:41 +0100Collected Evidence: Collected Evidence: Use ring-barking (girdling), cutting or silvicides to produce snags Of five studies found, one replicated and controlled study from the USA found that forest plots provided with snags had higher bird diversity and abundance than plots without snags added. Three studies from the USA and UK found that woodpeckers and other species used artificially-created snags for nesting and foraging. One study from the USA found that use increased with how long a snag had been dead. A UK study found that no crested tits used snags created for them, possibly because they were not rotted enough, or because they were too close to the ground.  Collected, 28 Jul 2012 20:29:12 +0100Collected Evidence: Collected Evidence: Use snakeskin to deter mammalian nest predatorsA randomised, replicated and controlled trial in the USA found that artificial nests were less likely to be predated if they had snake skin wrapped around them than control nests.  Collected, 16 Aug 2012 15:07:38 +0100Collected Evidence: Collected Evidence: Use ultrasonic devices to deter cats We found no evidence for the effects of ultrasonic cat deterrents on bird populations. '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, 16 Aug 2012 15:12:26 +0100Collected Evidence: Collected Evidence: Use supplementary feeding to reduce predation A controlled cross-over experiment from the UK found that there was no difference in grouse adult survival or productivity when supplementary food was provided to hen harrier Circus cyaneus compared to in control areas. This study and another from the USA that used artificial nests found that nest predation rates were reduced in areas when supplementary food was provided to predators. A second study from the USA found no such effect.  Collected, 16 Aug 2012 15:42:26 +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, 29 Aug 2012 13:32:11 +0100Collected Evidence: Collected Evidence: Use repellents to deter birds from landing on pools polluted by miningA randomised, replicated and controlled ex situ trial from the USA found that fewer common starlings Sturnus vulgaris consumed contaminated water when it was treated with repellents, compared to untreated water.  Collected, 29 Aug 2012 13:51:48 +0100Collected Evidence: Collected Evidence: Use volunteers to collect downed birds and rehabilitate them We found no evidence that report on the effectiveness of using volunteers to collect and rehabilitate downed 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, 29 Aug 2012 16:42:08 +0100Collected Evidence: Collected Evidence: Water nesting mounds to increase incubation success in malleefowlA small controlled in Australia found that two malleefowl Leipoa ocellata nests were abandoned after they dried out, despite being watered, although unwatered nests were abandoned much earlier.  Collected, 29 Aug 2012 16:48:28 +0100Collected Evidence: Collected Evidence: Use techniques to increase the survival of species after capture A small controlled study from the USA found that providing dark, quiet environments with readily-available food and water increased the survival of small birds after capture and increased the probability that they would accept captivity. A study from Hawaii found that keeping birds warm in a ‘mock’ translocation in Hawaii increased survival, although all birds suffered some loss of condition.  Collected, 06 Oct 2012 21:18:18 +0100Collected Evidence: Collected Evidence: Use vocalisations to attract birds to safe areas Six studies from North America, the Galapagos and the Azores found that seabirds were more likely to nest in areas where vocalisations were played, or were successfully attracted to nest in new areas, following the playing of vocalisations. Four of these studies used several interventions at once. One study found that some calls were more effective than others. Two studies from the USA and the Galapagos found that birds did not colonise all new areas where vocalisations were played. It is possible that the result from the Galapagos was due to only having a single year’s data. One controlled study from Hawaii found that albatross were more likely to land in areas where vocalisations were played than in areas without vocalisation playback. A small controlled study from New Zealand found that terns were not more likely to land in areas where vocalisations were played.  Collected, 06 Oct 2012 21:54:59 +0100Collected Evidence: Collected Evidence: Wash contaminated semen and use it for artificial inseminationA single replicated controlled study in Spain found that semen contaminated with urine could be successfully washed to increase its pH and produced three raptor nestlings.  Collected, 13 Oct 2012 16:47:48 +0100Collected Evidence: Collected Evidence: Use puppets to increase the survival or growth of hand-reared chicksThree replicated studies from the USA and Saudi Arabia found that corvids and bustards raised using puppets did not have higher survival, dispersal or growth than conventionally hand-reared chicks.  Collected, 14 Oct 2012 12:43:41 +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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