Collected Evidence: Collected Evidence: Remove ectoparasites from feathers to increase survival or reproductive success A replicated and controlled study in the UK found that red grouse Lagopus lagopus scoticus treated with spot applications had lower tick and disease burdens and higher survival than controls, whilst birds with impregnated tags had lower tick burdens only. A replicated ex situ study in Hawaii found that CO­2 was the most effective way to remove lice from feathers, although this treatment did not kill the lice.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F437https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F437Wed, 22 Aug 2012 15:30:29 +0100Collected Evidence: Collected Evidence: Remove ectoparasites from nests to increase survival or reproductive success Six of the seven studies that investigated infestation rates found lower rates in nests treated for ectoparasites, one (that used microwaves to treat nests) did not find fewer parasites. Two studies from the USA found higher survival or lower abandonment in nests treated for ectoparasites, whilst seven studies from across the world found no differences in survival, fledging rates or productivity between nests treated for ectoparasites and controls. Two studies from the USA and the UK found that chicks from nests treated for ectoparasites were in better condition than those from control nests. Four studies found no such effect.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F438https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F438Wed, 22 Aug 2012 18:20:13 +0100Collected Evidence: Collected Evidence: Reduce nest ectoparasites by providing beneficial nesting materialA randomised, replicated and controlled experiment in Canada found lower numbers of some, but not all, parasites in nests provided with beneficial nesting material, but that there was no effect on fledging rates or chick condition.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F439https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F439Thu, 23 Aug 2012 14:26:34 +0100Collected Evidence: Collected Evidence: Guard nests to reduce risk of ectoparasites We found no evidence on the effects of guarding nests to reduce the risk of ectoparasites '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%2F440https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F440Thu, 23 Aug 2012 14:27:25 +0100Collected Evidence: Collected Evidence: Remove/control adult brood parasites All 11 studies from across the world that investigated parasitism rates found that they were lower following cowbird Molothrus spp. control. One study from Ecuador found an increase in host species population after cowbird control, but two American studies found no such effect. Five studies from the Americas found higher productivities or success rates of host nests when cowbirds were removed, five found that at least some measures of productivity did not change with cowbird control.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F441https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F441Thu, 23 Aug 2012 14:28:02 +0100Collected Evidence: Collected Evidence: Remove brood parasite eggs from target species’ nests A controlled before-and-after study on Puerto Rico found lower rates of parasitism of yellow-shouldered blackbird Agelaius xanthomus nests when shiny cowbird Molothrus bonariensis eggs were removed from nests. A replicated, controlled study from 1997-1999 in grassy fields in New York State, USA found that song sparrow Melospiza melodia nests that had cowbird eggs removed from them had lower success than nests which were parasitised and that did not have eggs removed.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F443https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F443Thu, 23 Aug 2012 15:56:54 +0100Collected Evidence: Collected Evidence: Use false brood parasite eggs to discourage brood parasitismA replicated, controlled experiment in the USA found lower parasitism rates for red-winged blackbird Agelaius phoeniceus nests with false or real brown-headed cowbird Molothrus ater eggs added to them.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F444https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F444Thu, 23 Aug 2012 16:03:29 +0100Collected Evidence: Collected Evidence: Provide supplementary food to increase parental presence and so reduce brood parasitism We found no evidence on providing supplementary food to increase parental presence and so reduce boord parasitims 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 Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F445https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F445Thu, 23 Aug 2012 16:04:16 +0100Collected Evidence: Collected Evidence: Alter artificial nest sites to discourage brood parasitismA replicated trial from Puerto Rico found that brood parasitism levels were extremely high across all nest box designs tested.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F446https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F446Thu, 23 Aug 2012 16:06:05 +0100Collected Evidence: Collected Evidence: Use copper strips to exclude snails from nestsA single small, before-and-after study in Mauritius found no snail-caused chick mortality in 2004–7 after the installation of copper strips at seven echo parakeet Psittacula eques nest holes, compared to four fatalities in 2003–4.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F447https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F447Thu, 23 Aug 2012 16:08:25 +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: Relocate birds following oil spillsA replicated study in South Africa found that a higher percentage of African penguins Spheniscus demersus that were relocated following an oil spill bred at their old colonies, compared to birds which were rehabilitated after being oiled, despite fewer relocated birds being seen at their home colony.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F449https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F449Wed, 29 Aug 2012 13:27:22 +0100Collected Evidence: Collected Evidence: Deter or prevent birds from landing on toxic pools We found no evidence for the effects of deterring or preventing birds from landing on toxic pools '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%2F450https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F450Wed, 29 Aug 2012 13:28:14 +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 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 Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F453https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F453Wed, 29 Aug 2012 13:51:48 +0100Collected Evidence: Collected Evidence: Reduce pesticide or herbicide use generally A single small study from the UK investigated population level effects of reduced chemical inputs, and found that the populations of some species increased when pesticide use was restricted alongside other interventions. Three studies, two replicated, one controlled, from the UK found that some or all species were found at higher densities on sites with reduced pesticide inputs, in one case with other interventions as well. Five studies from the UK, four replicated, four controlled, found that some or all species were not found at higher densities on fields or sites with reduced chemical inputs, or were not associated with reduced inputs. A controlled before-and-after study from the UK found that grey partridge Perdix perdix chicks had higher survival on sites with reduced pesticide applications. A replicated study from the UK found that reduced chemical inputs had a negative relationship with partridge brood size and no relationship with survival or the ratio of young to old birds.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F454https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F454Wed, 29 Aug 2012 14:08:01 +0100Collected Evidence: Collected Evidence: Restrict certain pesticides or other agricultural chemicals for birdsA small scale study found that Pyrazophos reduced chick food abundance more than other foliar fungicides. A before-and-after study from Spain found that the population of griffon vultures Gyps fulvus increased in the study area following multiple interventions including the banning of strychnine.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F455https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F455Wed, 29 Aug 2012 14:24:27 +0100Collected Evidence: Collected Evidence: Provide food for vultures to reduce mortality from diclofenacA before-and-after trial in Pakistan found that oriental white-backed vulture Gyps bengalensis mortality rates were significantly lower when supplementary food was provided, compared to when it was not.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F456https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F456Wed, 29 Aug 2012 14:30:48 +0100Collected Evidence: Collected Evidence: Make selective use of spring herbicides We found no evidence for the effects of selective use of spring herbicides 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 Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F457https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F457Wed, 29 Aug 2012 14:33:12 +0100Collected Evidence: Collected Evidence: Use organic rather than mineral fertilisers We found no evidence for the effects of using organic, not mineral, fertilisers 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 Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F458https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F458Wed, 29 Aug 2012 14:34:08 +0100Collected Evidence: Collected Evidence: Reduce chemical inputs in permanent grassland managementA randomised, replicated, controlled study from the UK found that no more foraging birds were attracted to pasture plots with no fertiliser, compared to control plots.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F459https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F459Wed, 29 Aug 2012 14:37:13 +0100Collected Evidence: Collected Evidence: Leave headlands in fields unsprayed (conservation headlands) Three studies from Europe, two replicated, found that conservation headlands were frequently used by some of all of the bird species studied, or were strongly associated with species. A review from the UK found that grey partridge Perdix perdix populations were far larger on farms with conservation headlands and other interventions in place than other farms. Two replicated studies from Europe found that species were not associated with, or were no more abundant on, conservation headlands, compared with control fields. All four studies, three replicated, that investigated survival found higher grey partridge Perdix perdix chick or adult survival on sites with conservation headlands than control sites. One found that this difference was not significant. Five studies from Europe, four replicated, found larger grey partridge broods on farms with conservation headlands, one study found that differences were not significant. One replicated study from the UK found that fewer broods were found in fields with conservation headlands. Another replicated study from the UK found no relationship between conservation headlands and partridge brood size or young to adult ratio.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F461https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F461Wed, 29 Aug 2012 15:39:20 +0100Collected Evidence: Collected Evidence: Provide unfertilised cereal headlands in arable fields We found no evidence describing the effects of unfertilised cereal headlands 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 Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F462https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F462Wed, 29 Aug 2012 16:07:02 +0100Collected Evidence: Collected Evidence: Provide buffer strips along rivers and streams We did not find any evidence describing the impact of riparian strips on reducing water pollution and how this affected bird populations. However, riparian strips also provide valuable habitats in their own right. Studies describing the use of riparian strips by birds are described in ‘Habitat restoration and creation’. '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%2F463https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F463Wed, 29 Aug 2012 16:08:57 +0100Collected Evidence: Collected Evidence: Provide buffer strips around in-field ponds We found no evidence describing the effect of buffer strips around in-field ponds on pollution levels and 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 Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F464https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F464Wed, 29 Aug 2012 16:09:56 +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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