Collected Evidence: Collected Evidence: Legally protect habitats Four studies (two replicated) from Europe found population increases following habitat protection, more positive population trends in protected habitats, compared with outside, or with increases amounts of protected habitats. A literature review reported that a large number of cranes (Gruidae) of seven species used nature reserves in China, whilst a replicated, randomised and controlled study from Argentina found that some guilds of birds were found at higher species richnesses in protected forests, some at higher densities, and that some showed no differences. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F158https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F158Tue, 15 May 2012 13:48:22 +0100Collected Evidence: Collected Evidence: Increase the proportion of natural/semi-natural vegetation in the farmed landscape Of four studies captured, one, a replicated and controlled paired sites study from Australia, found that farms with plantings of native vegetation held more species than those without. The effect was smaller than that explained by variation in the amount of natural habitat remaining on farms. A replicated study from Switzerland found more species in areas under the Ecological Compensation Area scheme than areas not under it. A before-and-after study from Switzerland found that the populations of three bird species increased after an increase in the amount of land under the Ecological Compensation Scheme. This study found that three species were more found more than expected on Ecological Compensation Scheme land. Another replicated study from Switzerland found that some habitats held more birds if they were close to ECA habitat but that the amount of Ecological Compensation Scheme in an area had no impact on population densities. A small study from the UK found no effect of habitat creation on grey partridge populations. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F171https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F171Sun, 20 May 2012 13:21:01 +0100Collected Evidence: Collected Evidence: Manage hedges to benefit birds The one study of six that investigated species richness found no difference in species richness between a UK site with wildlife-friendly hedge management and three control sites. Seven studies from the UK and Switzerland, five replicated, found that some species studied increased in relation to managed hedges or were more likely to be found in managed hedges, compared to other habitats. Two investigated several interventions at once. One replicated study found that species that showed positive responses to hedge management in some regions showed weak or negative responses in other parts of the UK. Four studies from the UK found that some species declined or showed no response to wildlife-friendly management of hedges. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F177https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F177Wed, 30 May 2012 13:46:53 +0100Collected Evidence: Collected Evidence: Manage ditches to benefit wildlife Three out of four replicated studies from the UK found that some farmland birds responded positively to the presence of ditches managed for wildlife. All three also found that some species did not respond positively or responded negatively to management. A replicated, controlled and paired sites study from the UK found that bunded ditches were visited by more birds than non-bunded ditches. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F180https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F180Wed, 30 May 2012 14:17:50 +0100Collected Evidence: Collected Evidence: Leave refuges in fields during harvest A replicated study in France found that fewer gamebirds came into contact with mowing machinery when refuges were left in fields than when they were not left. A review from the UK found that Eurasian skylarks Alauda arvensis did not nest at higher densities in uncut refuges than in the rest of the fields.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F193https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F193Wed, 27 Jun 2012 17:35:08 +0100Collected Evidence: Collected Evidence: Increase crop diversity to benefit birdsA before-and-after study in the UK found that more barnacle geese Branta leucopsis used a site after the amount of land used to grow cereals was reduced and other interventions were used.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F201https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F201Thu, 28 Jun 2012 11:43:13 +0100Collected Evidence: Collected Evidence: Leave overwinter stubbles The three studies from the UK (one replicated) that report population-level changes found positive effects of over-winter stubble provision, but all investigated multiple interventions at once. Eight studies from the UK, including a systematic review, found that at least some species or groups of farmland birds were positively associated with over-winter stubbles, or were found on stubbles. Three studies investigated multiple interventions without separating the effects of each. Two studies reported that seed-eating birds in particular were more abundant on stubbles. One of the eight studies found that no more positive responses to stubbles were found than would be expected by chance. A replicated, randomised and controlled study from the UK found that 22 of 23 species did not preferentially use stubbles compared to cover crops. A replicated study from the UK found that the area of stubble in a site was negatively related to grey partridge Perdix perdix brood size. Five studies from the UK, four replicated, found that stubble management affected use by birds. Some species or groups were more common on cut stubbles, some on uncut and some showed preferences for barley over wheat. One study found that only Eurasian skylarks Alauda arvensis were more common on stubbles under agri-environment schemes, and only on highly prescriptive schemes. One study found that all seed-eating species were more abundant on stubbles under agri-environment schemes in one of two regions studied.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F203https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F203Mon, 09 Jul 2012 15:13:01 +0100Collected Evidence: Collected Evidence: Leave unharvested cereal headlands within arable fields We found no evidence for the effects of leaving unharvested cereal headlands within arable fields 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%2F206https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F206Sun, 15 Jul 2012 17:11:46 +0100Collected Evidence: Collected Evidence: Leave uncropped, cultivated margins or plots, including lapwing and stone curlew plots Two studies and two reviews examined population-level effects of uncropped margins or plots. A before-and-after study from the UK and two reviews found an increase in Eurasian thick-knee Burhinus oedicnemus numbers following a scheme that promoted plots (amongst other interventions); a replicated study from the UK found no effect of plots on grey partridge density changes. Four studies (three replicated) and a review from the UK found that at least one species was associated with lapwing plots or used them for foraging or nesting. One replicated study from the UK found that 11 species were not associated with plots; another found that fewer birds used the plots than cropland in two out of three UK regions. Two of the three studies that examined productivity (one replicated) found that nesting success of birds was higher in fallow fields or lapwing plots than in crops. A replicated study from the UK found that grey partridge Perdix perdix productivity was not related to the amount of lapwing plots on a site and that the proportion of young partridges in the population was lower on sites with lots of cultivated fallow plots.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F213https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F213Tue, 17 Jul 2012 11:09:12 +0100Collected Evidence: Collected Evidence: Maintain species-rich, semi-natural grassland A before-and-after study from the UK found five species of conservation concern increased after the implementation of management designed to maintain unimproved grasslands. A replicated study from Switzerland found that wetland birds appeared to preferentially choose managed hay meadows; birds of open farmland avoided it.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F218https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F218Tue, 17 Jul 2012 12:27:00 +0100Collected Evidence: Collected Evidence: Leave uncut rye grass in silage fields for birds Two reviews from the UK found that leaving rye grass uncut, or with only a single cut, benefited seed-eating birds and two replicated, controlled studies from the UK found that seed-eating birds were more abundant on uncut plots. Two replicated and controlled studies and a review, all from the UK, found that seed-eating birds were more abundant on uncut and ungrazed plots than on uncut and grazed plots. A replicated, controlled study from the UK found that the responses of non-seed-eating birds were less certain than seed-eaters, with some species avoiding uncut rye grass.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F224https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F224Tue, 17 Jul 2012 15:04:39 +0100Collected Evidence: Collected Evidence: Maintain lowland heathland We found no intervention-based evidence on the effects of maintaining lowland heath 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%2F226https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F226Tue, 17 Jul 2012 15:31:29 +0100Collected Evidence: Collected Evidence: Maintain rush pastures We found no intervention-based evidence on the effects of maintaining rush pastures 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%2F227https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F227Tue, 17 Jul 2012 15:32:25 +0100Collected Evidence: Collected Evidence: Maintain traditional water meadows A replicated study from the UK found that northern lapwing and common redshank populations increased on nature reserves managed to maintain water meadows. Two replicated studies from the Netherlands found that there were more waders or birds overall on specially managed meadows or 12.5 ha plots including several management interventions than on conventional fields, but one study found that these differences were present before the management scheme was introduced and the other found no differences between individual fields under different management. A replicated study from the UK found that common snipe decreased on nature reserves managed to maintain water meadows and a replicated before-and-after study from the Netherlands found that wader population trends on specially managed meadows were no different to those on conventionally-managed meadows. A replicated study from the UK found that lapwing populations on three of four water meadow sites managed for conservation did not have high enough productivity to maintain population levels. All three sites were judged deficient in at least one management category.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F229https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F229Tue, 17 Jul 2012 15:37:55 +0100Collected Evidence: Collected Evidence: Maintain upland heath/moorA literature review from the UK found that agri-environment guidelines on moorland grazing were leading to increased bird populations in one region. There were localised problems with overgrazing, burning and scrub encroachment.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F230https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F230Tue, 17 Jul 2012 15:50:00 +0100Collected Evidence: Collected Evidence: Maintain wood pasture and parkland We found no intervention-based evidence on the effects of maintaining wood pasture and parkland 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%2F235https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F235Tue, 17 Jul 2012 15:57:02 +0100Collected Evidence: Collected Evidence: Maintain traditional orchardsTwo site comparison studies from the UK and Switzerland found that traditional orchards did not benefit many birds. In Switzerland, one species was associated with orchards; in the UK, the focal species was negatively related to the presence of orchards.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F240https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F240Wed, 18 Jul 2012 10:42:12 +0100Collected Evidence: Collected Evidence: Increase water turbidity to reduce fish predation by birdsA randomised trial in France found that little egret Egretta garzetta foraging efficiency was lower in turbid water than clear.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F252https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F252Wed, 18 Jul 2012 12:45:59 +0100Collected Evidence: Collected Evidence: Insulate power pylons to prevent electrocutionA single before-and-after study in the USA found the insulating power pylons significantly reduced the number of Harris’s hawks Parabuteo unicinctus electrocuted.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F268https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F268Thu, 19 Jul 2012 16:10:27 +0100Collected Evidence: Collected Evidence: Increase ‘on-the-ground’ protection to reduce unsustainable levels of exploitation Two before-and-after studies from Central America and Europe found increases in recruitment and population levels following either stricter anti-poaching measures or stricter protection and the stationing a warden on an island. However, the Central American study found that recruitment increases were only maintained for as long as the intensive effort was continued.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F272https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F272Thu, 19 Jul 2012 17:38:04 +0100Collected Evidence: Collected Evidence: Introduce voluntary ‘maximum shoot distances’A replicated, randomised before-and-after study from Denmark found that significantly fewer pink-footed geese Anser brachyrhynchus were wounded but not killed, following the implementation of a voluntary maximum shooting distance.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F279https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F279Tue, 24 Jul 2012 12:44:12 +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: 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: 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: 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 +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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