Conservation Evidence: Evidence Data

Collected Evidence: Collected Evidence: Create uncultivated margins around intensive arable or pasture fields Thirty-nine studies (including 13 replicated controlled trials of which three also randomized and four reviews) from eight European countries compared wildlife on uncultivated margins with other margin options. Twenty-four found benefits to some wildlife groups (including 11 replicated controlled trials of which one also randomised, and four reviews). Nineteen studies (including one randomized, replicated, controlled trial) from Germany, Ireland, Lithuania, Norway, the Netherlands and the UK found uncultivated margins support more invertebrates (including bees) and/or higher plant diversity or species richness than conventionally managed field margins or other field margin options. One replicated, controlled study showed that uncultivated margins supported more small mammal species than meadows and farmed grasslands. Four studies (two replicated UK studies, two reviews) reported positive associations between birds and field margins including food provision. A review from the UK found grass margins (including naturally regenerated margins) benefited plants and some invertebrates. Fifteen studies (including one randomized, replicated, controlled trial) from Germany, the Netherlands, Norway and the UK found that invertebrate and/or plant species richness or abundance were lower in naturally regenerated than conventionally managed fields or sown margins. Six studies (including one randomized, replicated, controlled trial) from Belgium, Germany and the UK found uncultivated margins did not have more plant or invertebrate species or individuals than cropped or sown margins. A review found grass margins (including naturally regenerated margins) did not benefit ground beetles. Five studies (including three replicated controlled trials) from Ireland and the UK reported declines in plant species richness and invertebrate numbers in naturally regenerated margins over time. One replicated trial found that older naturally regenerated margins (6-years old) had more invertebrate predators (mainly spiders) than newly established (1-year old) naturally regenerated margins. Five studies (including one replicated, randomized trial) from the Netherlands and the UK found that cutting margins had a negative impact on invertebrates or no impact on plant species. One replicated controlled study found cut margins were used more frequently by yellowhammers when surrounding vegetation was >60 cm tall. Seven studies (including four replicated controlled trials and a review) from Ireland, the Netherlands, Norway and the UK reported increased abundance or biomass of weed species in naturally regenerated margins. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F63https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F63Tue, 04 Oct 2011 14:51:45 +0100Collected Evidence: Collected Evidence: Reduce management intensity on permanent grasslands (several interventions at once) A total of 32 individual studies from the Czech Republic, Germany, Ireland, the Netherlands, Switzerland and the UK looked at the effects on farmland wildlife of reducing management intensity on permanent grasslands. Twenty-two studies found benefits to some or all wildlife groups studied. Eleven studies (including four replicated site comparisons and three reviews) found reduced management intensity on permanent grassland benefited plants. Sixteen studies (including eight site comparisons of which four paired and three reviews) found benefits to some or all invertebrates. Five studies (including two replicated site comparisons, of which one paired, and a review) found positive effects on some or all birds. Twenty-one studies from six European countries found no clear effects of reducing management intensity on some or all plants, invertebrates or birds. Seven studies (including two replicated paired site comparisons and a review) found no clear effect on plants. Ten studies (including four site comparisons and one paired site comparison) found mixed or no effects on some or all invertebrates. Two studies (one review, one site comparison) found invertebrate communities on less intensively managed grasslands were distinct from those on intensively managed grasslands. Four studies (including three site comparisons, of which one paired and two replicated) found no clear effects on bird numbers or species richness. Five studies from four European countries found negative effects of reducing management intensity on plants, invertebrates or birds. Two studies (one review, one replicated trial) found some plant species were lost under extensive management. Two studies (one paired site comparison) found more invertebrates in grasslands with intensive management. One paired site comparison found fewer wading birds on grasslands with reduced management intensity than on conventionally managed grassland. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F69https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F69Mon, 24 Oct 2011 19:11:58 +0100Collected Evidence: Collected Evidence: Manage hedgerows to benefit wildlife (includes no spray, gap-filling and laying) Ten studies from Switzerland and the UK (three replicated and controlled studies of which one was randomized) found that managing hedges for wildlife resulted in increased berry yields, species diversity or richness of plants and invertebrates and diversity or abundance of farmland birds. Five studies from the UK (including one replicated, controlled and randomized study) found that hedge management did not affect plant species richness, numbers of bumblebee queens or farmland birds. Two replicated studies have shown mixed or adverse effects, with hedge management having mixed effects on invertebrates or leading to reduced hawthorn berry yield. A replicated site comparison in the UK found hedges cut every two years had more suitable nesting habitat for grey partridge than other management regimes. A replicated study from the UK found that hawthorn berry yield was reduced when management involved removing fruit-bearing wood. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F116https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F116Tue, 01 Nov 2011 20:32:06 +0000Collected Evidence: Collected Evidence: Restore or create traditional water meadows Of three studies from Sweden and the UK (two before-and-after trials) looking at bird numbers or densities following water meadow restoration, one study found increases, one study found increases and decreases and one found northern lapwing populations did not increase despite an increase in the area of managed water meadows. Seventeen studies from France, Germany, the Netherlands, Poland, Switzerland and the UK (seven replicated controlled studies of which two were also randomized and two reviews) found one or more management techniques that were successful in restoring wet meadow plant communities. The techniques were topsoil removal, introduction of target plant species, raising water levels, grazing, mowing or a combination of removing topsoil and introducing target plant species, plus livestock exclusion. Three studies (one replicated controlled study and two reviews) from the Netherlands, Sweden, Germany and the UK found restoration of wet meadow plant communities had reduced or limited success. Thirteen studies (five replicated and controlled of which two randomized) from France, Germany, the Netherlands, Switzerland and the UK monitored the effects of methods to restore or create wet meadow plant communities over a relatively short time period after restoration, and found some positive effects within five years. Three replicated studies (one controlled, one a site comparison) from the Netherlands and Germany found restoration was not complete five, nine or 20 years later. A replicated controlled site comparison from Sweden found plant species richness increased with time since restoration. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F119https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F119Tue, 01 Nov 2011 20:58:31 +0000Collected Evidence: Collected Evidence: Reduce tillage A total of 42 individual studies (including seven replicated, controlled and randomized studies and six reviews) from Belgium, Denmark, France, Germany, Hungary, Ireland, Lithuania, the Netherlands, Slovakia, Switzerland and the UK investigated the effects of reducing tillage on farmland wildlife. Thirty-four studies (of which 21 were replicated and controlled and seven also randomized, and five reviews) from nine European countries found some positive effects on earthworms, some invertebrates (other than earthworms), weeds or farmland birds, of reducing tillage compared to conventional management. Positive effects included increased biomass, species richness or abundance of earthworms, greater abundance of some invertebrates other than earthworms, increased numbers of some weeds and/or weed species, higher Eurasian skylark nest density, earlier laying date and shorter foraging distances on reduced tillage fields, and greater abundance of some birds - including Eurasian skylark, seed-eating songbirds and gamebirds in late winter on non-inversion or conservation tillage. A review found tillage had negative effects on invertebrate numbers and no-till systems had more invertebrate bird food resources. Twenty-six studies (of which 13 replicated and controlled and three also randomized, and five reviews) from nine European countries found reducing tillage had either negative, no effect or no consistent effects on abundance, biomass, or species richness of some invertebrates (other than earthworms), earthworm abundance, biomass, or species richness, number of different plant species found as seeds, number of some weed species, mammal abundance, some bird species, and one study found bird preferences for conservation tillage fields decreased over time. Two studies found that crop type affected the number of weeds under different tillage regimes. One small replicated trial in the UK compared bird numbers under two different forms of reduced tillage, and found more birds from species that make up the ‘Farmland Bird Index’ on broadcast than non-inversion tillage fields. Two studies looked at the long-term effects of reduced tillage on earthworms (after ten years). One study found higher earthworm biomass under reduced tillage, the other study found earthworm abundance was the same between conventional and reduced tillage plots. Three of the studies mentioned above did not distinguish between the effects of reducing tillage and reduced pesticide and/or fertilizer inputs. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F126https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F126Mon, 14 Nov 2011 18:00:22 +0000Collected Evidence: Collected Evidence: Restore/create species-rich, semi-natural grassland Twenty-eight studies monitored the effects on wildlife of restoring species-rich grassland. Of these, 20 from Finland, Germany, Lithuania, Sweden, Switzerland and the UK (15 replicated of which eight controlled and three also randomized) found restoring species-rich grassland resulted in higher ground beetle abundance, increased plant species richness, farmland bird abundance, pollinating insect density and diversity and earthworm abundance than other types of grassland, or that restored grasslands had similar abundance and species richness of insects to old traditionally managed sites. Seven studies from Denmark, Finland, Sweden, Switzerland and the UK (five replicated and controlled, two also randomized) found that efforts to restore species-rich grassland had no clear effect on the species richness or abundance of plants, beetles, or the abundance of butterflies and moths. Three replicated studies from Sweden and the UK (one also controlled and two site comparisons) found that restored grassland had a lower diversity and frequency of certain plant species, and attracted fewer foraging queen bumblebees than continuously grazed or unmanaged grasslands. We captured 40 studies (including 19 replicated and controlled studies of which six were also randomized, and six reviews) from nine European countries that found ten different techniques used alone or in combinations were effective for restoring species-rich grassland. Effective techniques included: grazing, introducing plant species, hay spreading and mowing. We found 22 studies from seven European countries that included information on the length of time taken to restore grassland communities (including 16 replicated trials of which nine also controlled and three reviews). Six studies saw positive signs of restoration in less than five years, 11 studies within 10 years and two studies found restoration took more than 10 years. Six studies found limited or slow changes in plant communities following restoration. Two studies from Germany and the UK (one replicated controlled trial) found differences in vegetation between restored and existing species-rich grasslands nine or 60 years after restoration. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F133https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F133Tue, 15 Nov 2011 18:41:52 +0000Collected Evidence: Collected Evidence: Reduce fertilizer, pesticide or herbicide use generally Of 38 individual studies from Austria, the Czech Republic, Denmark, Finland, France, Germany, Ireland, the Netherlands, Sweden and the UK investigating the effects of reducing fertilizers, pesticides or herbicides, 34 studies (23 replicated, of which six also controlled and randomized, one review and one systematic review) found benefits to some invertebrates, plants, or farmland birds. Twenty-five studies (16 replicated, of which seven also randomized and controlled and one review) found negative, mixed, minimal or no effects on some invertebrates, farmland birds or plants. Ten studies (six replicated, controlled studies of which two randomized) from three countries found positive effects of reducing or stopping pesticide applications on invertebrates, plants, or birds. Eight studies (two replicated controlled and randomized, one paired before-and-after trial) from four countries found inconsistent or no effects on some invertebrates or birds. Ten studies (nine replicated, five also controlled and a European systematic review) from four countries found positive effects of reducing or stopping herbicide use on plants, invertebrates, and birds. Five replicated studies (two also controlled and randomized) from three countries found no or mixed effects on birds, invertebrates and plants. Five studies (three replicated controlled of which two randomized) from four countries found positive effects of reducing or stopping fertilizer applications on invertebrates, Eurasian skylark, or plants. Four studies (three replicated, controlled and randomized) from two countries found reducing or stopping fertilizer inputs had no, or no consistent effects on some invertebrates and farmland birds. Two studies from the UK (one replicated) found plots where fertilizer inputs were not reduced tended to have higher earthworm biomass or abundance. Fifteen studies (three replicated controlled of which one also randomized, five site comparisons and one review) from seven countries looked at the effects of reducing or stopping applications of two or more inputs: pesticides, herbicides, or fertilizers. Thirteen studies found positive effects of reducing two or more inputs on some or all invertebrates, plants, soil organisms, and birds studied. Seven studies found negative or no effects of reducing combinations of inputs on some invertebrates, plants or birds. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F139https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F139Fri, 18 Nov 2011 20:06:45 +0000Collected Evidence: Collected Evidence: Provide or retain set-aside areas in farmland We found 34 studies comparing use of set-aside areas with control farmed fields. Two were reviews, none were randomized, replicated, controlled trials. Of these, 20 (from Austria, Finland, Germany and the UK) showed benefits to or higher use by all wildlife groups considered. Twelve (from Finland, Germany, Ireland, Sweden and the UK) found some species or groups used set-aside more than crops, others did not. Two studies (all from the UK) found no effect, one found an adverse effect of set-aside. Three of the studies, all looking at skylarks, went beyond counting animal or plant numbers and measured reproductive success. Two from the UK found higher nest survival or productivity on set-aside than control fields. One from the UK found lower nest survival on set-aside. Fifteen studies (from Belgium, Germany, Sweden and the UK) monitored wildlife on set-aside fields, or in landscapes with set-aside, without directly comparing with control fields or landscapes. Three looked at set-aside age and found more plants or insects on set-aside more than a year old. Two compared use of different non-crop habitats and found neither insects nor small mammals preferred set-aside. Two showed increased bird numbers on a landscape scale after set-aside was introduced, amongst other interventions. Eight looked at effects of set-aside management such as use of fertilizer and sowing or cutting regimes. A systematic review from the UK found significantly higher densities of farmland birds on fields removed from production and under set-aside designation than on conventionally farmed fields in both winter and summer. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F156https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F156Thu, 29 Mar 2012 19:03:54 +0100Collected Evidence: Collected Evidence: Plant grass buffer strips/margins around arable or pasture fields Nineteen studies from Finland, the Netherlands, Sweden and the UK (including seven replicated controlled studies of which two were randomized, and three reviews), found that planting grass buffer strips (some margins floristically-enhanced) increased arthropod abundance, species richness and diversity. A review found grass margins benefited bumblebees and some other invertebrates but did not distinguish between the effects of several different margin types. Nine studies from the UK (including seven replicated studies of which two were controlled, and two reviews) found that planting grass buffer strips (some margins floristically-enhanced) benefits birds, resulting in increased numbers, densities, species richness and foraging time. Seven studies from the Netherlands and the UK (all replicated of which four were controlled and two randomized), found that planting grass buffer strips (some margins floristically-enhanced) increased the cover and species richness of plants. A review found grass margins benefited plants but did not distinguish between the effects of several different margin types. Five studies from Finland and the UK (including two replicated, controlled trials and a review), found that planting grass buffer strips benefits small mammals: including increased activity and numbers. Six studies from the Netherlands and the UK (including three replicated, controlled trials) found that planting grass buffer strips had no clear effect on insect numbers, bird numbers or invertebrate pest populations. A replicated site comparison found sown grassy margins were not the best option for conservation of rare arable plants. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F246https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F246Wed, 18 Jul 2012 11:47:21 +0100Collected Evidence: Collected Evidence: Plant nectar flower mixture/wildflower strips A total of 80 individual studies have in some way investigated the effects of flowering strips on biodiversity. Sixty-four individual studies show some benefits to one or more wildlife groups. Sixty-five individual studies reported the effects of flower strips on invertebrates. Of these, fifty reported positive effects. Forty-one studies from eight European countries (including five reviews and twenty-three replicated controlled studies, of which one randomized and two site comparisons) found evidence that flower strips had a positive influence on invertebrate numbers with increased abundance, species richness/diversity, or both. Ten studies (nine replicated of which two controlled) found invertebrates visited or foraged on flower strips but did not specify increases/decreases in numbers. Two studies found effects on ground beetles other than changes in numbers. One replicated controlled study showed that ground beetles were more active or had enhanced feeding/reproductive conditions in flower strips. A review found flower strips supported ground beetle species that were rarely found in crops. Fifteen studies reported mixed or negative effects of flower strips on invertebrates. Six studies found no significant effects. Twenty-one studies looked at the effects of flower strips on plants. Sixteen studies from seven European countries (including ten replicated controlled studies of which one randomized) found evidence that flower strips had higher plant cover, number of flowers, diversity, and species richness. One review found flower strips benefited plants but did not specify how. Four studies found negative or no effects of flower strips on the number or diversity of plant species. Five studies described the effects of different margin establishment or management techniques on plants. Seven studies investigated birds and wildflower strips. Four replicated, controlled studies from Switzerland and the UK (two of which were randomized) and one review of European studies found evidence that plots sown with a wildflower or legume seed mix had a positive influence on birds. Flower strips attracted more birds or bird species and the number of birds using flower strips increased over time. Eurasian skylarks preferentially foraged in, and nested in or near, sown weed patches and were less likely to abandon their territories when they included sown weed patches. However one replicated trial in Switzerland found barn owls avoided sown wildflower areas. Two winter recording periods of the same replicated, controlled study in the UK found there were not more bird species or individuals on wildflower plots compared to control margins. All five studies investigating the effects of wildflower strips on small mammals (four replicated studies from Switzerland and one review of studies from north-western Europe) found evidence that small mammals benefit from strips sown with wildflowers or flowers rich in pollen and nectar, with increases in abundance, density and species richness. One replicated study from Switzerland reported that most common vole home ranges and core regions of their territories were found within a wildflower strip. Nineteen studies (of which eight replicated, controlled) reported positive effects on biodiversity of sowing specific plant species including phacelia, and/or other plant species such as borage and red clover. Three replicated studies (two also controlled) found negative impacts or no effects on biodiversity of sowing phacelia. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F442https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F442Thu, 23 Aug 2012 15:37:16 +0100Collected Evidence: Collected Evidence: Leave cultivated, uncropped margins or plots (includes 'lapwing plots') Nineteen individual studies looked at the effect of uncropped, cultivated margins or plots on wildlife. Seventeen studies from the UK and northwest Europe (six reviews and seven replicated studies of which two were site comparisons, one a before-and-after trial and one was controlled and randomized) found that leaving uncropped, cultivated margins or plots on farmland provides benefits to some or all target farmland bird species, plants, invertebrates, and mammals. These wildlife benefits included increased species richness of plants, bumblebees, species richness and abundance of spiders, abundance of ground-dwelling invertebrates and ground beetles, increased stone curlew breeding population size, northern lapwing hatching success, Eurasian skylark nesting success and the establishment, abundance or species richness of rare arable plant species. A replicated study found northern lapwing, Eurasian skylark, grey partridge and yellow wagtail bred in lapwing plots. Two studies (a replicated study and a review) from the UK found that leaving uncropped, cultivated margins or plots on farmland had no effect on 11 out of 12 farmland bird species or ground beetles. A replicated site comparison study in the UK found fewer seed-eating birds on fallow plots for ground-nesting birds in two out of three regions. One review from the UK found evidence that pernicious weeds were more commonly found on uncropped cultivated margins than conservation or conventional headlands. A replicated site comparison from the UK found the proportion of young grey partridges in the population was lower in areas with a high proportion of uncropped cultivated margins and plots. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F562https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F562Tue, 25 Sep 2012 14:57:25 +0100Collected Evidence: Collected Evidence: Plant wild bird seed or cover mixture Thirty individual studies investigated the effects on birds of sowing wild bird seed or cover mixture, 21 studies found positive effects. Fourteen studies from the UK (including one systematic review and nine replicated controlled trials of which four randomized, and three reviews) found that fields sown with wild bird cover mix had higher abundance, density, species diversity and species richness of birds than other farmland habitats. Six studies from the UK (including one review and two replicated studies) found that birds showed a preference for wild bird cover and used it significantly more than other habitats. One review found the grey partridge population increased substantially on farms where conservation measures including cover crops were in place. Nine replicated studies from France and the UK reported mixed or negative effects of wild bird cover on birds compared to other farmland habitats. Six studies found that mixtures including kale or a mixture of kale and/or other species attracted the largest number of bird species or highest bird abundance. Twelve studies from the UK looked at the effects of wild bird cover strips on invertebrates. Seven studies from the UK (including one review and four replicated controlled studies of which two were also randomized) found positive effects. Farmland habitats sown with wild bird cover mix were used more by butterflies, and had a higher abundance or species richness of butterflies and/or bees than other farmland habitats. One review found wild bird cover benefited invertebrates. Four studies (including one review and two replicated trials) reported mixed or negative effects of wild bird cover on invertebrate numbers compared with other farmland habitats. One study found that bees and butterflies showed preferences for particular plant species. Eight studies from the UK looked at plants and wild bird cover. Six studies (including two reviews and two replicated controlled trials) found that planting wild bird cover mix was one of the three best options for conservation of annual herbaceous plant communities, benefited plants and resulted in increased plant diversity and species richness. However two replicated studies (of which one a site comparison) found mixed/negative effects for plant species richness. One replicated trial from the UK found that small mammal activity was higher in wild bird cover than in the crop in winter but not in summer. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F594https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F594Fri, 12 Oct 2012 14:56:56 +0100Collected Evidence: Collected Evidence: Provide supplementary food for birds or mammals A total of 18 individual studies investigated the effects of providing supplementary food. Nine studies from France, Sweden and the UK (six replicated studies, of which five controlled and one also randomized and paired) found that the provision of supplementary food increased farmland bird abundance, breeding population size, density, body mass, hatching, nestling growth and fledging rates, increased overwinter survival of a declining house sparrow population and that fed male hen harriers bred with more females than control birds. Two studies did not separate the effects of several other interventions carried out on the same study site. Four studies from the UK and Finland (three replicated studies, of which one controlled and one randomized) found that farmland songbirds and field voles (field voles on unmown plots only) used supplementary food when provided, including the majority of targeted species such as tree sparrow, yellowhammer and corn bunting. Five replicated studies from the UK (of which two also controlled) found that the provision of supplementary food had no clear effect on farmland bird breeding abundance, European turtle dove reproductive success, territory size or territory density, overwinter survival of three stable house sparrow populations, tree sparrow nest box use, or the abundance of weed seeds on the soil surface. One replicated, controlled study from Sweden found no effect of supplementary food provision on common starling clutch size or nestling weight, and lower fledging rates in nests which received supplementary food compared to nests without supplementary food in one year. Four studies from the UK (two replicated of which one was also randomized and controlled) found that the use of supplementary food by farmland birds varied between species and region, depended upon the time of year and proximity to other feeding stations and natural feeding areas. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F648https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F648Thu, 18 Oct 2012 14:20:34 +0100Collected Evidence: Collected Evidence: Create beetle banks Fourteen reports from eight studies out of a total 24 reports from 12 individual studies (including eight replicated studies of which three controlled and four literature reviews) from Denmark and the UK found that beetle banks provide some benefits to farmland biodiversity. Sixteen reports from eight individual studies looked at invertebrates and beetle banks. Five reports from two replicated studies (of which one controlled) and a review found positive effects on invertebrate densities/numbers, distribution, or higher ground beetle density and species diversity in spring and summer but not winter. Six reports from three replicated studies (of which one randomized and controlled) found that invertebrate numbers varied between specific grass species sown on beetle banks. Two replicated studies (one paired and controlled) found that the effect of beetle banks varied between invertebrate groups or families. Five replicated studies (of which two controlled) found lower or no difference in invertebrate densities or numbers on beetle banks relative to other habitats. One review found lesser marsh grasshopper did not forage on two plant species commonly sown in beetle banks. Six studies looked at birds and beetle banks. Two reviews and one replicated controlled trial found positive effects on bird numbers (in combination with other farmland conservation measures) or evidence that birds used beetle banks. Two studies (one replicated site comparison) found mixed effects on birds. One replicated study found no farmland bird species were associated with beetle banks. One replicated, paired, controlled study and a review looked at the effects of beetle banks on plants and found either lower plant species richness on beetle banks in summer, or that grass margins including beetle banks were generally beneficial to plants but these effects were not pronounced on beetle banks. One controlled study and a review found beetle banks acted as nest sites for harvest mice. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F651https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F651Tue, 23 Oct 2012 16:24:44 +0100Collected Evidence: Collected Evidence: Leave headlands in fields unsprayed (conservation headlands) Twenty-two studies from 14 replicated, controlled experiments (of which two randomized) including two reviews, from a total of 32 studies from 20 experiments (of which 17 replicated, controlled) including three reviews from Finland, Germany, the Netherlands, Sweden and the UK that investigated species richness and diversity of farmland wildlife found that conservation headlands contained higher species richness or diversity of invertebrates or plants than other habitat types. Twelve studies (including a review) from ten replicated experiments (of which eight controlled and three controlled and randomized) found that some or all invertebrates or plants investigated did not have higher species richness or diversity on conservation headlands compared to other habitat types. This included both replicated, controlled studies investigating bee diversity. Two replicated studies from the UK found that unfertilized conservation headlands had more plant species than fertilized conservation headlands. Positive effects of conservation headlands on abundances or behaviours of some or all species investigated were found by 27 studies from 15 replicated experiments (of which 13 controlled) including five reviews out of a total of 36 studies from 20 experiments (17 replicated, controlled) including five reviews from Finland, Germany, the Netherlands, Sweden and the UK that investigated birds (some studies looked at number of visits), mammals (some studies looked at number of visits), invertebrates and plant abundance/cover. One review from the UK found a positive effect on grey partridge populations but did not separate the effects of several other interventions including conservation headlands. Nineteen studies from 13 replicated (12 controlled) experiments and a review from Finland, Germany, the Netherlands and the UK found that some or all species of birds, invertebrates or plants investigated were at similar, or lower, abundances on conservation headlands compared to other management. One review from the UK and a study in Germany found conservation headlands had a positive effect on plants and some, but not all invertebrates, or rare arable weeds but did not specify how. All eight studies from the UK and Sweden that investigated species’ productivity, from three replicated (two controlled) experiments including two reviews found that grey partridge productivity or survival was higher in conservation headlands (or in sites with conservation headlands), compared to other management. One replicated study from the UK found that conservation headlands did not increase the proportion of young grey partridges in the population. A before-and-after study from the UK found that some invertebrates in conservation headlands survived pesticide applications to neighbouring fields. A review found crop margins reduce the effects of spray drift on butterflies. A replicated study from Germany and a review found that conservation headlands appeared to prevent or reduce the establishment and spread of pernicious weeds. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F652https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F652Wed, 31 Oct 2012 09:36:44 +0000Collected Evidence: Collected Evidence: Leave overwinter stubbles Eighteen studies (including four reviews and one systematic review) investigated the effects of overwinter stubbles on farmland wildlife. Thirteen studies from Finland, Switzerland and the UK (six replicated trials, including two site comparisons, four reviews and a systematic review) found evidence that leaving overwinter stubbles provides some benefits to plants, insects, spiders, mammals and farmland birds. These benefits include higher densities of farmland birds in winter, increased grey partridge productivity, and increased cirl bunting population size (in combination with several other conservation measures) and territory density. One replicated site comparison study from the UK found evidence that leaving overwinter stubbles had inconsistent or no effects on farmland bird numbers. Three studies found only certain bird species showed positive associations with overwinter stubbles. Two replicated studies (of which one also randomized and controlled) found that only Eurasian skylark or both Eurasian skylark and Eurasian linnet benefited, out of a total 23 and 12 farmland bird species tested respectively. One study found that only grey partridge and tree sparrow showed positive population responses to areas with overwinter stubbles. Two studies from the UK (one randomized, one replicated and controlled) found that different farmland bird species benefited from different stubble heights. One replicated site comparison found mixed effects between different stubble management options on seed-eating bird abundance. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F695https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F695Sun, 02 Dec 2012 12:01:18 +0000Collected Evidence: Collected Evidence: Pay farmers to cover the cost of conservation measures (as in agri-environment schemes) Twenty-six studies from four European countries (including one UK systematic review and three European reviews) looked at the effects of agri-environment schemes on birds. Twenty-four studies (including one systematic review, six site comparisons and nine reviews) found increases in population size, density or more favourable population trends of some or all birds studied on sites with agri-environment schemes compared to non-scheme sites (some of these differences were seasonal). Eleven studies (including one systematic review and four reviews) found negative or no effects. One UK study found higher numbers of some birds where higher tier management was in place, another UK study found no difference between Entry Level or Higher Level Stewardship Scheme fields. One study from the Netherlands found that not all agri-environment scheme agreements were sited in ideal locations for black-tailed godwit. Eleven studies from five European countries (including three replicated paired site comparisons and two reviews) looked at the effects of agri-environment schemes on plants. Seven studies (including three replicated paired site comparisons and one European review) found agri-environment schemes maintained or had little or no effect on plants, plant diversity or species richness. Three studies found increases in plant species richness in areas with agri-environment schemes, two found decreases. A replicated site comparison study from Estonia found higher flower abundance on farms with agri-environment schemes in two out of four areas. A review found Environmentally Sensitive Areas in England had contributed to halting the loss of semi-natural grassland habitats but were less effective at enhancing or restoring grassland biodiversity. Ten studies from three European countries (including two replicated paired site comparisons and a review) looked at the effects of agri-environment schemes on invertebrates. Six studies (including two replicated site comparisons) showed agri-environment schemes maintained or had little or no effect on some invertebrates in terms of diversity, abundance, species richness or bee colony growth. Five studies found increases in abundance or species richness of some invertebrates. A UK study found agri-environment scheme prescriptions had a local but not a landscape-scale effect on bee numbers. Four studies (including two replicated site comparisons and a review) from the UK looked at the effects of agri-environment schemes on mammals. One study found positive effects, three studies found mixed effects in different regions or for different species. Three of the studies above found higher numbers of wildlife on land before agri-environment schemes were introduced. However two studies collecting baseline data found no difference in the overall number of birds or earthworms and soil microorganisms between areas with and without agri-environment schemes. A review found two out of three agri-environment schemes in Europe benefited wildlife. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F700https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F700Fri, 21 Dec 2012 14:38:13 +0000Collected Evidence: Collected Evidence: Maintain species-rich, semi-natural grassland Of 22 studies (including eleven replicated trials, three reviews and a systematic review) from the Czech Republic, Finland, Germany, Russia, Slovenia, Switzerland and the UK, 13 identified management regimes that maintained species-rich grassland. Four of these studies were replicated, controlled trials (including two randomized). Nine studies (including two randomized, replicated before-and-after trials) from Switzerland and the UK examined the effectiveness of existing or historical agri-environment schemes: seven testing the effectiveness of the Environmentally Sensitive Areas scheme in England and two testing the effectiveness of the Ecological Compensation Areas scheme in Switzerland. All except one reported mixed results, with the schemes broadly maintaining plant species richness, but being less effective, for example, in enhancing species richness, preserving the highest quality sites, or overcoming the effects of past intensive management. One study found six Environmentally Sensitive Areas were of ‘outstanding’ significance for their lowland grassland, containing >40% of the English resource of a grassland type. A replicated site comparison study found that on average 86% of Swiss Ecological Compensation Area litter meadows were of ‘good ecological quality’ compared with only 20% of hay meadow Ecological Compensation Areas. Twelve studies (including a systematic review, six replicated trials of which two also controlled and randomized, and three reviews) from the Czech Republic, Finland, Germany, Slovenia, Switzerland and the UK tested the effects of management treatments on species richness or vegetation quality usually involving combinations of mowing, grazing or no fertilizer but some also tested the effectiveness of mulching or burning. All of these studies identified management treatments which benefited or maintained species richness or vegetation quality. One site comparison from Finland and northwest Russia found that butterfly species richness, diversity and total abundance did not differ significantly between mown meadows and grazed pastures and that grassland age and origin had a greater impact on butterfly communities than present management. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F702https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F702Mon, 28 Jan 2013 11:44:12 +0000Collected Evidence: Collected Evidence: Reduce grazing intensity on grassland (including seasonal removal of livestock) Of 27 individual studies (including 10 replicated, controlled trials, four reviews and one systematic review) from France, Germany, Ireland, the Netherlands and the UK, 15 (including three randomized, replicated, controlled trials) from four countries found benefits to birds, plants or invertebrates in response to reducing grazing intensity on permanent grassland (including seasonal removal of livestock). Of these 15 studies, six (including one randomized, replicated, controlled trial) found that reducing grazing intensity throughout the year increased the abundance and diversity of plants (Tallowin et al. 2005, Marriott et al. 2009), frequency of certain plant species, invertebrate diversity, usage by geese and the number of northern lapwing and common redshank. Six studies (including three replicated controlled trials of which two randomized) found that excluding or delaying summer grazing increased plant species diversity, invertebrate abundance and benefited breeding Eurasian skylark. A review found a study that showed that removing autumn grazing after a silage cut increased the winter abundance of seed-eating birds. A review and a replicated controlled study from the UK found that reduced grazing intensity or seasonal removal of livestock increased the number of invertebrates, plant seed heads and foraging skylark, and that some bird species preferred plots with seasonal removal of livestock. Three studies (including one randomized, replicated, controlled trial) from the Netherlands and the UK found no benefit to plants or invertebrates from reduced grazing intensity. One randomized, replicated controlled trial excluded grazing in autumn/winter and another study excluded grazing in the summer. A further study found that reducing grazing intensity throughout the year did not increase plant diversity. Nine studies from France, Germany and the UK reported mixed results for some or all species or wildlife groups considered (including one randomized, replicated, controlled trial and two reviews and a systematic review). Of these, eight studies found that reduced grazing intensity throughout the year benefited some species but not others, one found that the impact depended on the type of vegetation grazed, and one found benefits to bee and wasp abundance but not species richness. One study found that the response of birds to removal of summer grazing varied between functional groups and depended on time of year. A UK review found that reduced grazing benefited invertebrates, plants, rodents and some but not all birds. A systematic review of the effects of grazing intensity on meadow pasture concluded that intermediate levels of grazing are usually optimal for plants, invertebrates and birds but that trade-offs are likely to exist between the requirements of different taxa. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F704https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F704Tue, 29 Jan 2013 17:33:20 +0000