Collected Evidence: Collected Evidence: Introduce agri-environment schemes to benefit wild beesFour replicated trials in Europe have shown enhanced diversity and/or abundance of foraging wild bees on land managed under various European agri-environment schemes, relative to conventionally-managed fields or field margins. These schemes were the Swiss Ecological Compensation Areas (one replicated trial), the German organic arable farming option (one replicated trial), the Dutch botanical and meadow bird agreements (one replicated trial, very low numbers of bee species) and the Scottish Rural Stewardship Scheme (one replicated trial, also included nest-searching queen bumblebees). Four replicated trials in Europe found that the number of bees and/or bee species is not enhanced on land managed under agri-environment schemes, including meadow bird agreements in wet grassland in the Netherlands, measures to protect steppe-living birds and compensation measures around a National Park in Spain, and 6 m wide grass field margin strips in England (one replicated trial for each). On a wider landscape scale, two replicated trials in the UK have found bumblebee populations were not enhanced on farmland managed under agri-environment schemes. One trial compared the reproductive success of colonies of the buff-tailed bumblebee Bombus terrestris, the other compared queen bumblebee numbers in spring in conventionally managed field margins, on farms with and without agri-environment schemes.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F24https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F24Thu, 20 May 2010 16:11:07 +0100Collected Evidence: Collected Evidence: Create patches of bare ground for ground-nesting beesOne replicated controlled trial in Germany and four small trials (three replicated, one not) have shown that artificially exposed areas of bare soil can be successfully colonised by ground-nesting solitary bees and wasps in the first or second year. We have captured no evidence for the effect of creating areas of bare ground on bee populations or communities on a larger scale.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F13https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F13Thu, 20 May 2010 19:29:53 +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: Undersow spring cereals, with clover for example Three studies from the UK, two replicated, found that there were higher densities of some study species on undersown fields or margins, compared with other fields, or that use of fields increased after they were undersown. One of these (reported in two places) found that not all species nested at higher densities. One replicated study from the UK found that various measures of grey partridge population health declined as the amount of undersown cereal on sites increased. A replicated study from the UK found no relationship between the amount of undersown cereals on a site and the productivity of grey partridge on that site.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F208https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F208Sun, 15 Jul 2012 17:28:25 +0100Collected Evidence: Collected Evidence: Revert arable land to permanent grassland All five studies looking at the effects of reverting arable land to grassland found no clear benefit to birds. The studies monitored birds or grey partridges in the UK and wading birds in Denmark (4). They included three replicated controlled trials. One of the studies, a controlled before-and-after study from the UK, showed that grey partridge numbers fell significantly following the reversion of arable fields to grassland.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F210https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F210Sun, 15 Jul 2012 18:00:36 +0100Collected Evidence: Collected Evidence: Delay haying/mowing Two reviews from the UK found that the population of corncrakes Crex crex increased following the implementation of two initiatives to encourage farmers to delay mowing (and provide cover and use corncrake-friendly techniques). A replicated and controlled paired sites study from the Netherlands found no evidence that waders and other birds were more abundant in fields with delayed mowing, compared to paired controls. A replicated and controlled before-and-after study from the Netherlands found that fields with delayed mowing held more birds than controls, but did so before the start of the scheme. Population trends did not differ between treatments. A replicated, controlled study from the USA found that destruction of nests by machinery was lower and late-season nesting higher in late-cut fields, compared with early-cut fields.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F223https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F223Tue, 17 Jul 2012 14:29:48 +0100Collected Evidence: Collected Evidence: Disturb birds at roosts One controlled study from the USA investigated the effects of harassment on fish predation, and found there were fewer double-crested cormorants Phalacrocorax auritus on, and fewer fish were taken from, fish ponds near roosts which were harassed, compared with undisturbed roosts. A review found that there was a reduction in the number of cormorants foraging near roosts after night-time disturbance. Four studies, two replicated, from the USA and Israel, found that cormorants moved away from roosts where they were disturbed at night. One study found that this effect was only temporary.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F245https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F245Wed, 18 Jul 2012 11:42:12 +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 prescribed burning on savannas A replicated and controlled study from Kenya, of five studies captured, found that burned areas of savanna tended to have more birds and more species than control or grazed areas. However, the authors note that differences were not present during drought years and burned sites showed significant annual variation, unlike grazed sites. A replicated and controlled study from Australia found that the effects of burning on bird abundances depended on burn season, and habitat type. Two replicated studies in the USA found that some open country species were more common in burned areas than unburned, whilst other species were less so. A small study from the USA found that two eastern bluebird Sialia sialis successfully raised chicks after the habitat around their nest boxes was subject to a prescribed burn.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F320https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F320Thu, 26 Jul 2012 14:58:00 +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 Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F343https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F343Sat, 28 Jul 2012 20:29:12 +0100Collected Evidence: Collected Evidence: Restore or create traditional water meadows Four out of five before-and-after studies, all from the UK, found that the number of waders and wildfowl on sites increased following the restoration of water meadows. One before-and-after study from Sweden found no increase in northern lapwing population following an increase in the area of managed meadows in the study area. This study also found that restored meadows were used less than expected by breeding lapwings. A before-and-after study from Sweden found that hatching success of northern lapwings were higher on meadows than on spring-sown crops. There were no differences between meadows and autumn-sown crops or grasslands.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F363https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F363Mon, 06 Aug 2012 12:51:09 +0100Collected Evidence: Collected Evidence: Control mammalian predators on islands for songbirds Two before-and-after trials in the Seychelles and Cook Islands describe population increases in magpie robins and monarch flycatchers following cat and rat control. A before-and-after study from New Zealand found that the population of South Island robins Petroica australis australis was almost identical before and after rat control. Two studies found higher reproductive success in monarch flycatchers and shrikes in areas with rodent control, compared to areas without control. However, this was climate dependent in shrikes. A before-and-after study from Hawaii found lower predation on artificial nests after intensive rodent control.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F382https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F382Wed, 08 Aug 2012 14:43:04 +0100Collected Evidence: Collected Evidence: Control predators not on islands for gamebirds Four controlled studies in Europe found increased populations or productivity of grouse and partridges on sites with predator removal. One study tested multiple interventions simultaneously. A fifth replicated UK study found no increase in grouse densities or reproductive success on sites with gamekeepers, compared to those without.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F387https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F387Wed, 08 Aug 2012 17:25:00 +0100Collected Evidence: Collected Evidence: Physically protect nests with individual exclosures/barriers or provide shelters for chicks of songbirds Three studies from across the world found increased fledging success for nests in trees protected by individual barriers. A replicated controlled study from the USA also found higher success for ground-nests protected by individual barriers. Two studies from the UK and Japan found lower predation rates on nests protected by individual barriers.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F400https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F400Thu, 16 Aug 2012 13:13:40 +0100Collected Evidence: Collected Evidence: Remove topsoil or turf before seeding/planting Six studies examined the effects of removing topsoil or turf before seeding/planting on grassland vegetation. Three studies were in the UK, two studies were in the USA and one was in France. VEGETATION COMMUNITY (3 STUDIES) Community composition (1 study): One replicated, randomized, controlled study in France found that removing topsoil before sowing seeds increased plant community similarity to that of intact steppe. Overall richness/diversity (1 study): One replicated, randomized, controlled study in France found that removing topsoil before sowing seeds increased plant species richness. Sown/planted species richness/diversity (1 study): One replicated, controlled study in the UK found that removing topsoil before sowing seeds increased the species richness of sown plants. Grass richness/diversity (1 study): One replicated, randomized, paired, controlled study in the UK found that removing turf before sowing seeds increased grass species richness in most cases compared to disturbing the soil before sowing. Forb richness/diversity (1 study): One replicated, randomized, paired, controlled study in the UK found that removing turf before sowing seeds increased forb species richness in most cases compared to disturbing the soil before sowing. VEGETATION ABUNDANCE (2 STUDIES) Overall abundance (1 study): One replicated, randomized, controlled study in France found that removing topsoil before sowing seeds did not alter overall vegetation cover. Sown/planted species abundance (1 study): One replicated, randomized, controlled study in the UK found that removing topsoil before planting seedlings led to higher cover of planted species. Individual species abundance (1 study): One replicated, randomized, controlled study in the UK found that removing topsoil before planting seedlings led to lower cover of common knapweed. VEGETATION STRUCTURE (0 STUDIES) OTHER (2 STUDIES) Survival (2 studies): Two replicated, controlled studies (one paired and one randomized) in the USA found that removing topsoil before planting California oatgrass or sowing and planting purple needlegrass increased the survival of seedlings and plants. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3415https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3415Fri, 25 Jun 2021 16:09:07 +0100Collected Evidence: Collected Evidence: Add mulch before or after seeding/planting Six studies examined the effects of adding mulch before or after seeding/planting on grassland vegetation. Two studies were in Canada, two were in the USA, and one study was in each of the UK and Germany. VEGETATION COMMUNITY (1 STUDY) Characteristic plant richness/diversity (1 study): One replicated, controlled study in Germany found that adding mulch before sowing seeds did not alter the species richness of target plants. VEGETATION ABUNDANCE (4 STUDIES) Overall abundance (1 study): One replicated, controlled study in Canada found that adding mulch before sowing seeds did not increase plant cover. Characteristic plant abundance (1 study): One replicated, controlled study in Germany found that adding mulch before sowing seeds increased the cover of target plant species. Sown/planted species abundance (2 studies): One of two replicated, randomized, controlled studies in the USA and UK found that adding mulch before sowing seeds did not alter the density of six sown plant species in most cases. The other study found that adding mulch before planting seedlings reduced the cover of planted species. Individual species abundance (1 study): One replicated, randomized, controlled study in the UK found that adding mulch before planting seedlings did not alter the cover of common knapweed. VEGETATION STRUCTURE (0 STUDIES) OTHER (2 STUDIES) Germination/Emergence (1 study): One replicated, controlled study in Canada found that adding mulch before sowing seeds increased the number of seedlings in most cases. Growth (1 study): One replicated, randomized, controlled study in the USA found that adding mulch after planting native prairie plants did not alter the growth of any of seven plant species. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3425https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3425Mon, 28 Jun 2021 10:05:54 +0100Collected Evidence: Collected Evidence: Manage land under power lines for butterflies and moths Six studies evaluated the effects on butterflies and moths of managing land under power lines for butterflies and moths. Two studies were in each of the USA and Finland, and one was in each of the UK and Canada. COMMUNITY RESPONSE (3 STUDIES) Richness/diversity (3 studies): Two replicated, site comparison studies (including one paired study) in Finland found that land under power lines managed by mechanical cutting had a higher species richness of butterflies than unmanaged land, and butterfly species richness was highest 2–4 years after scrub and trees were cleared. One replicated, site comparison study in Canada found that the species richness of butterflies was similar under power lines and on road verges mown once or twice a year, or left unmown. POPULATION RESPONSE (6 STUDIES) Abundance (6 studies): One of two replicated, site comparison studies (including one paired study) in Finland and Canada found that land under power lines managed by mechanical cutting had a higher abundance of butterflies than unmanaged land. The other study found that land under power lines and on road verges managed by mowing had a lower abundance of pearl crescent and northern pearl crescent butterflies, and a similar abundance of other butterflies, to those left unmown. Two of three site comparison studies (including two replicated studies) in the USA, the UK and Finland found that the time since management under power lines did not affect the abundance of Karner blue butterflies or small pearl-bordered fritillaries, but chequered skipper abundance was higher in areas cleared ≤2 years ago than in areas cut ≥4 years earlier. The other study found that power lines cleared of trees and scrub 2–4 years earlier had a higher abundance of butterflies than power lines cleared 1 year or 6–8 years earlier. Two site comparison studies in the USA found that land under power lines managed by cutting or herbicide application, and by mowing or cutting, had a similar abundance of Karner blue butterflies and six other butterfly species, but the abundance of frosted elfin was higher under power lines managed by mowing than those managed by cutting. BEHAVIOUR (1 STUDY) Use (1 study): One replicated, site comparison study in the UK reported that pearl-bordered fritillaries used areas under power lines where scrub had been cleared one or two years earlier, but not under power lines cleared three or more years ago. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3855https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3855Tue, 05 Jul 2022 12:26:37 +0100Collected Evidence: Collected Evidence: Leave headlands in fields unsprayed (conservation headlands) Six studies evaluated the effects on butterflies and moths of leaving headlands in fields unsprayed. Four studies were in the UK, and two were in the Netherlands. COMMUNITY RESPONSE (2 STUDIES) Richness/diversity (2 studies): Two replicated, paired, controlled studies in the UK and the Netherlands found that unsprayed headlands in arable fields had a greater species richness of butterflies than headlands sprayed with herbicide and insecticide. POPULATION RESPONSE (5 STUDIES) Abundance (5 studies): Four of five replicated, controlled studies (including one randomized study) in the UK and the Netherlands found that unsprayed headlands in arable and pasture fields had a greater abundance of butterflies and caterpillars than headlands sprayed with herbicide and insecticide. The other study found that unsprayed headlands in arable fields had a similar abundance of caterpillars to headlands sprayed with herbicide. BEHAVIOUR (1 STUDY) Use (1 study): One replicated, paired, controlled study in the UK found that large white, small white and green-veined white butterflies spent more time in unsprayed arable headlands than adjacent hedgerows, but more time in the hedgerows when adjacent headlands were sprayed with herbicide. The same study found that gatekeepers spent more time in hedgerows than headlands regardless of whether the headlands were unsprayed or sprayed. Behaviour change (1 study): One replicated, paired, controlled study in the UK found that large white, small white and green-veined white butterflies spent more time feeding and interacting, or had slower flight speeds, in unsprayed arable headlands than in headlands sprayed with herbicide. However, the same study found that male gatekeepers spend less time feeding and interacting, and had faster flight speeds, in unsprayed headlands than in sprayed headlands. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3898https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3898Tue, 09 Aug 2022 14:23:30 +0100Collected Evidence: Collected Evidence: Restore or create habitat connectivity Six studies evaluated the effects on butterflies and moths of restoring or creating habitat connectivity. Three studies were in the USA, two were in the UK and one was in Sweden. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (4 STUDIES) Abundance (4 studies): Four studies (including one controlled, before-and-after study and one before-and-after study) in the USA and the UK found that restoring connectivity between lupine, bracken, pastures or prairie patches increased the abundance of Karner blue, high brown fritillary, small pearl-bordered fritillary, marsh fritillary and regal fritillary. BEHAVIOUR (2 STUDIES) Use (2 studies): One site comparison study in Sweden reported that grassland strips providing nectar or shelter were each more likely to be used by one of four butterfly species than strips with no resources. One replicated, controlled study in the USA found that common buckeye and variegated fritillary butterflies were more likely to move between connected than unconnected habitat patches. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3934https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3934Sat, 13 Aug 2022 14:42:44 +0100Collected Evidence: Collected Evidence: Thin trees within forests Six studies evaluated the effects on butterflies and moths of thinning trees within forests and woodland. Three studies were in the USA and one was in each of Côte d’Ivoire, Finland and the Czech Republic. COMMUNITY RESPONSE (5 STUDIES) Community composition (1 study): One site comparison study in Côte d’Ivoire found that rarer species of fruit-feeding butterfly were less frequently caught in a forest managed by thinning than in an unmanaged, naturally regenerating forest. Richness/diversity (6 studies): Four studies (including two replicated, paired, controlled, before-and-after studies) in the USA and Finland found that one, two or four years after management, coniferous woodland which had been thinned, along with either prescribed burning, mulching or nearby felling, had a greater species richness of butterflies, or butterflies, diurnal moths and bumblebees combined, than either unmanaged woodland or before management. One site comparison study in Côte d’Ivoire found that a forest managed by thinning had a similar species richness and diversity of fruit-feeding butterflies to an unmanaged, naturally regenerating forest. One replicated, paired sites, controlled study in the Czech Republic found that partially-cleared forest plots had higher butterfly but lower moth species richness than plots of closed-canopy forest. POPULATION RESPONSE (5 STUDIES) Abundance (5 studies): Four studies (including two replicated, paired, controlled, before-and-after studies) in the USA and Finland found that one, two or four years after management, coniferous woodland which had been thinned, along with either prescribed burning, mulching or nearby felling, had a higher abundance of all butterflies, or specialist butterflies, than either unmanaged woodland or before management. One site comparison study in Côte d’Ivoire found that a forest managed by thinning had a similar abundance of fruit-feeding butterflies to an unmanaged, naturally regenerating forest. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3940https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3940Sat, 13 Aug 2022 14:57:16 +0100Collected Evidence: Collected Evidence: Restore or create grassland/savannas Six studies evaluated the effects on butterflies and moths of restoring or creating grassland or savanna. Three studies were in the USA, two were in the UK, and one was in Italy. COMMUNITY RESPONSE (1 STUDY) Richness/diversity (1 study): One replicated, paired, site comparison study in Italy found that created semi-natural grasslands had a greater diversity of butterflies than adjacent conifer forests, but a lower diversity than species-rich pastures. POPULATION RESPONSE (4 STUDIES) Abundance (4 studies): Two site comparison studies (including one replicated, paired study) in Italy and the USA found that created semi-natural grasslands and restored grasslands and oak barrens had a higher abundance of butterflies and regal fritillaries than adjacent conifer forests, species-rich pastures or unmanaged or remnant prairies. One site comparison study in the USA found that prairies restored 5–10 years ago by seeding with native species, mowing, and weeding or applying herbicide, had a greater abundance of Fender’s blue eggs than a prairie restored 1–2 years ago, and a similar abundance to remnant prairies. One study in the USA reported that restored prairie supported a translocated population of regal fritillaries for at least three years after restoration. BEHAVIOUR (3 STUDIES) Use (2 studies): One of two replicated, before-and-after studies in the UK reported that following grassland restoration the area occupied by small pearl-bordered fritilliaries increased. The other study reported that following grassland restoration the number of marsh fritillary populations at each site remained the same or increased. Behaviour change (1 study): One site comparison study in the USA found that Fender’s blue butterflies spent a similar proportion of time laying eggs in prairies restored 5–10 years ago by seeding with nectar species, mowing, and weeding or applying herbicide, and in remnant prairies. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3943https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3943Sat, 13 Aug 2022 14:58:03 +0100Collected Evidence: Collected Evidence: Restore or create peatland Six studies evaluated the effects on butterflies and moths of restoring or creating peatland. Two studies were in each of Finland and the UK, and one was in each of the Netherlands and Ireland. COMMUNITY RESPONSE (3 STUDIES) Community composition (1 study): One replicated, paired, site comparison study in Finland found that mires restored by filling ditches and cutting trees had a moth community which was intermediate between drained and pristine mires. Richness/diversity (2 studies): One replicated, paired, controlled, before-and-after study in Finland found that after mires were restored by raising the water table and removing large trees, they had a higher species richness of mire specialist butterflies than before restoration or than unrestored, drained mires, and a similar species richness to pristine mires. One replicated, paired, site comparison study in Ireland reported that protected bogs re-wetted by blocking drains had a similar species richness of moths to unrestored and unprotected bogs. POPULATION RESPONSE (5 STUDIES) Abundance (4 studies): Two before-and-after studies (including one replicated, paired, controlled study) in the UK and Finland found that bogs re-wetted by blocking drains and mires restored by raising the water table and removing large trees had a higher abundance of rosy marsh moth caterpillars and mire specialist butterflies than before restoration or than unrestored mires, and a similar abundance to pristine mires. Two replicated, paired, site comparison studies in Finland and Ireland found that mires restored by filling ditches and cutting trees and bogs restored by blocking drains (along with legal protection) had mixed effects on moth abundance compared to unrestored sites depending on species. Survival (1 study): One replicated study in the UK found that where water levels had risen due to peatland restoration, large heath butterfly caterpillars had lower winter survival than in areas where water levels had not risen. BEHAVIOUR (1 STUDY) Use (1 study): One replicated, site comparison study in the Netherlands found that wet heathland where water levels had been recently raised were less frequently occupied by Alcon large blue than sites where the water level had not been raised. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3948https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3948Sat, 13 Aug 2022 14:59:56 +0100Collected Evidence: Collected Evidence: Restore or create species-rich, semi-natural grassland Six studies evaluated the effects on butterflies and moths of restoring or creating species-rich, semi-natural grassland. Two studies were in Finland, and one was in each of Switzerland, Sweden, the UK and Germany. COMMUNITY RESPONSE (3 STUDIES) Community composition (1 study): One replicated, site comparison study in the UK found that semi-natural grasslands restored by scrub clearance and the reintroduction of grazing or mowing had different butterfly communities to existing species-rich grasslands, and they did not become more similar over time. Richness/diversity (3 studies): One of two replicated, site comparison studies in Finland and Sweden found that semi-natural grasslands restored by scrub clearance and grazing had a similar species richness of butterflies and burnet moths to both unrestored and continuously managed grassland. The other study found that semi-natural grasslands restored by cattle grazing had a lower species richness of butterflies and day-flying moths than unrestored and continuously managed grasslands. One replicated, site comparison study in the UK found that the species richness of butterflies on semi-natural grasslands restored by scrub clearance and the reintroduction of grazing or mowing remained similar over time since restoration. POPULATION RESPONSE (5 STUDIES) Abundance (5 studies): Two of five replicated, site comparison studies (including one paired study) in Switzerland, Finland, Sweden and Germany found that semi-natural grasslands restored by cattle grazing had a lower total abundance of butterflies and day-flying moths, and of 13 out of 32 individual species, than unmanaged, abandoned grasslands, but that three species had higher abundance, and three had lower abundance, on restored grasslands than on continuously grazed grasslands. Two studies found that grasslands restored by scrub clearing and grazing or mowing had a similar abundance of butterflies and burnet moths and heath fritillaries to unmanaged grasslands and continuously managed grasslands, although the abundance of heath fritillary adults and caterpillars was lower on restored grasslands than on continuously managed grasslands. The fifth study found that the density of blue-spot hairstreak eggs, and egg batches, was higher in grasslands restored by scrub cutting than in unrestored or continuously managed grasslands. BEHAVIOUR (1 STUDY) Use (1 study): One replicated, site comparison study in Germany found that in grasslands restored by scrub cutting, a greater proportion of small buckthorn bushes contained blue-spot hairstreak eggs than in unrestored or continuously managed grasslands. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3955https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3955Sun, 14 Aug 2022 10:35:55 +0100Collected Evidence: Collected Evidence: Reduce cutting frequency on grassland Six studies evaluated the effects on butterflies and moths of reducing cutting frequency on grassland. One study was in each of Slovakia, the Czech Republic, Hungary, the UK, Germany and Italy. COMMUNITY RESPONSE (3 STUDIES) Richness/diversity (3 studies): Two of three replicated studies (including one randomized, paired, controlled study and two site comparison studies) in the UK, Germany and Italy found that meadows cut once/year had a higher species richness of butterflies (along with other pollinators) and moths than meadows cut two or more times/year. The other study found that meadows cut one, two or three times/year all had a similar species richness of butterflies. POPULATION RESPONSE (5 STUDIES) Abundance (5 studies): Three of five replicated studies (including two randomized, paired, controlled studies and three site comparison studies) in Slovakia, the Czech Republic, Hungary, the UK and Italy and found that meadows cut once/year had a similar abundance of all butterflies, and of meadow brown adults and caterpillars and scarce large blue adults, to meadows cut two or three times/year. The other two studies found that meadows cut occasionally or once/year had a higher abundance of Scotch argus and pollinators (including butterflies) than intensively mown grasslands and meadows cut twice/year. BEHAVIOUR (0 STUDIES)  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3961https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3961Sun, 14 Aug 2022 10:37:38 +0100Collected Evidence: Collected Evidence: Use rotational grazing Six studies evaluated the effects on butterflies and moths of using rotational grazing. Three studies were in France, two were in the USA and one was in the UK. COMMUNITY RESPONSE (5 STUDIES) Community composition (1 study): One replicated, site comparison study in the USA found that rotational, cattle-grazed grasslands had a similar butterfly community to continuously grazed or patch-burned grasslands. Richness/diversity (5 studies): Two of four replicated studies (including one randomized, controlled study, two controlled studies and one site comparison study) in France and the USA found that rotational cattle- and sheep-grazed grasslands had a greater species richness of butterflies and burnet moths than continuously grazed or patch-burned grassland. Another of these studies found that rotationally sheep-grazed grassland had a similar species richness of butterflies and burnet moths to continuously grazed grassland. The other study found that rotational cattle-grazed pastures had a greater species richness of butterflies than constantly grazed pastures but only at a high, not low, stocking density. One replicated, site comparison study in the USA found that rotationally managed grasslands, including some rotationally grazed grasslands, which were last managed longer ago had a higher species richness of butterflies than more recently managed grasslands. POPULATION RESPONSE (6 STUDIES) Abundance (6 studies): Two of four replicated, controlled studies (including two randomized studies and one paired study) in France and the UK found that rotational cattle- and sheep-grazed grassland had a higher abundance of butterflies and burnet moths and caterpillars (along with other invertebrates) than continuously grazed grasslands. However, one of these studies only found this in the first of three years of management. Another of these studies found that rotationally sheep-grazed grassland had a similar abundance of butterflies and burnet moths to continuously grazed grassland. The other study found that rotational cattle-grazed pastures had a higher abundance of butterflies than constantly grazed pastures but only at a high, not low stocking density. One replicated, site comparison study in the USA found that the abundance of two species was higher, two species were lower and the other five species did not differ in rotationally cattle-grazed grasslands compared to continuously grazed or patch-burned grasslands. One replicated, site comparison study in the USA found that rotationally managed grasslands, including some rotationally grazed grasslands, which were last managed longer ago had a higher abundance of butterflies than more recently managed grasslands. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3965https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3965Sun, 14 Aug 2022 10:38:22 +0100
What Works 2021 cover

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.

More about What Works in Conservation

Download free PDF or purchase
The Conservation Evidence Journal

The Conservation Evidence Journal

An online, free to publish in, open-access journal publishing results from research and projects that test the effectiveness of conservation actions.

Read the latest volume: Volume 21

Go to the CE Journal

Discover more on our blog

Our blog contains the latest news and updates from the Conservation Evidence team, the Conservation Evidence Journal, and our global partners in evidence-based conservation.


Who uses Conservation Evidence?

Meet some of the evidence champions

Endangered Landscape ProgrammeRed List Champion - Arc Kent Wildlife Trust The Rufford Foundation Save the Frogs - Ghana Mauritian Wildlife Supporting Conservation Leaders
Sustainability Dashboard National Biodiversity Network Frog Life The international journey of Conservation - Oryx Cool Farm Alliance UNEP AWFA Bat Conservation InternationalPeople trust for endangered species Vincet Wildlife Trust