Collected Evidence: Collected Evidence: Protect in-field trees (includes management such as pollarding and surgery) We have captured no evidence for the effects of protecting in-field trees on farmland wildlife. '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%2F75https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F75Mon, 24 Oct 2011 21:07:09 +0100Collected Evidence: Collected Evidence: Provide foraging perches (eg. for shrikes) We have captured no evidence for the effects of providing foraging perches (eg. for shrikes) on farmland wildlife. '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%2F79https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F79Mon, 24 Oct 2011 21:12:45 +0100Collected Evidence: Collected Evidence: Provide nest boxes for bees (solitary bees or bumblebees) Ten studies (nine replicated trials and a review of studies) from Germany, Poland and the UK of solitary bee nest boxes all showed the nest boxes were readily used by bees. Two replicated studies found the local population size or number of emerging red mason bees increased when nest boxes were provided. One replicated trial in Germany showed that the number of occupied solitary bee nests almost doubled over three years with repeated nest box provision at a given site. Two replicated trials tested bumblebee nest boxes and both found very low uptake, 2% or less. Occupancy rates of solitary bee nest boxes, where reported (two replicated studies), were between 1 and 26% of available cavities. Five studies (four replicated trials and a review of studies) report the number of bee species found in the nest boxes – between 4.6 and 33 species. One replicated study from Germany found nest boxes should be placed 150-600 m from forage resources (Gathmann & Tscharntke 2002). A replicated study from Poland found the highest production of red mason bees per nest was from nesting materials of reed stems or wood. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F80https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F80Mon, 24 Oct 2011 21:15:42 +0100Collected Evidence: Collected Evidence: Provide red squirrel feeders We have captured no evidence for the effects of providing red squirrel feeders on farmland wildlife. '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%2F82https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F82Mon, 24 Oct 2011 21:21:16 +0100Collected Evidence: Collected Evidence: Provide otter holts We have captured no evidence for the effects of providing otter holts on farmland wildlife. '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%2F83https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F83Mon, 24 Oct 2011 21:22:28 +0100Collected Evidence: Collected Evidence: Provide badger gates We have captured no evidence for the effects of providing badger gates on farmland wildlife. '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%2F84https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F84Mon, 24 Oct 2011 21:23:17 +0100Collected Evidence: Collected Evidence: Provide bat boxes, bat grilles, improvements to roosts We have captured no evidence for the effects of providing bat boxes, bat grilles or improvements to roosts on farmland wildlife. '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%2F95https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F95Mon, 24 Oct 2011 21:39:48 +0100Collected Evidence: Collected Evidence: Re-wet moorland We have captured no evidence for the effects of re-wetting moorland on farmland wildlife. '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%2F103https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F103Mon, 24 Oct 2011 21:57:49 +0100Collected Evidence: Collected Evidence: Protect individual nests of ground-nesting birds Two replicated, randomized, controlled studies from Sweden found providing nest exclosures offered some benefits to ground-nesting birds. One study found that protected nests had higher average daily survival rates than unprotected nests for both common redshank and northern lapwing, however, this study also reported higher predation of adult redshank on protected nests. One study found that the average hatching rate for southern dunlin was higher for protected rather than unprotected nests. This study also found no difference in the number of fledglings, breeding adults or new recruits during two periods with and without nest protection.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F108https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F108Mon, 24 Oct 2011 22:04:47 +0100Collected Evidence: Collected Evidence: Provide medicated grit for grouse A controlled study in England found that red grouse had higher productivity in areas where medicated grit was provided. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F112https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F112Mon, 24 Oct 2011 22:12:09 +0100Collected Evidence: Collected Evidence: Provide training for land managers, farmers and farm advisers One study from the UK found farmers who were trained in how to implement agri-environment schemes created better quality wildlife habitat over five years. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F113https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F113Mon, 24 Oct 2011 22:13:06 +0100Collected Evidence: Collected Evidence: Provide specialist advice, assistance preparing conservation plans We have captured no evidence for the effects of providing specialist advice and/or assistance in preparing conservation plans on farmland wildlife. '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%2F114https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F114Mon, 24 Oct 2011 22:14:27 +0100Collected Evidence: Collected Evidence: Provide short grass for birds A replicated UK study found that common starlings and northern lapwing spent more time foraging on short grass, compared to longer grass, and that starlings captured more prey in short grass. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F115https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F115Mon, 24 Oct 2011 22:15:43 +0100Collected Evidence: Collected Evidence: Provide other resources for birds (water, sand for bathing) A small study in France found that grey partridge density was higher in areas where a combination of supplementary food, water, shelter and sand for bathing were provided.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F117https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F117Tue, 01 Nov 2011 20:37:30 +0000Collected Evidence: Collected Evidence: Provide buffer strips alongside water courses (rivers and streams) Three studies (including one replicated site comparison) from the Netherlands and the UK reported that the provision of riparian buffer strips had a positive influence on plant, invertebrate and bird diversity or abundance, and supported vegetation associated with habitats preferred by water voles. Two replicated site comparison studies from France and Ireland found that the provision of riparian buffer strips on farms did not result in an increase in the number of plant species when compared to farms without buffer strips. One replicated site comparison study found ground beetle diversity was higher in grazed riparian zones and narrow fenced strips than in wide riparian buffer strips. However the ground beetle assemblages in wide riparian buffer strips were more distinct from the adjacent pasture field assemblages than either the grazed riparian zones or narrow fenced strips. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F120https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F120Tue, 01 Nov 2011 21:03:36 +0000Collected Evidence: Collected Evidence: Raise water levels in ditches or grassland Seven studies from Denmark, the Netherlands and the UK (two replicated controlled studies and two before-and-after studies) found that raising water levels in ditches or grassland was associated with increased bird numbers, breeding bird numbers, plant species that favour wet conditions, and invertebrate numbers or biomass in agricultural landscapes. Two replicated studies from the Netherlands and the UK found that raising water levels resulted in a net loss of plant species and did not affect lapwing foraging rate. A review found three studies reporting that re-wetting soils on old arable fields is not an effective method of reducing nutrient levels and restoring species-rich grassland. A replicated study from the UK found that unflooded pastures contained a high biomass of soil macroinvertebrates of importance to breeding wading birds. A controlled, randomized study from the Netherlands found that raising the water level resulted in a more rapid establishment of species typical of wet grassland, than vegetation management. A review of agri-environment schemes from the UK found studies that suggested more expensive agri-environment scheme options for wetland habitats, such as controlling water levels, were more effective at providing good habitat for wading birds than easier-to-implement options. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F121https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F121Tue, 01 Nov 2011 21:14:13 +0000Collected Evidence: Collected Evidence: Raise mowing height on grasslands to benefit farmland wildlife A replicated controlled study and a review from the UK found that raised mowing heights provided benefits to Eurasian skylark including increased productivity. A review found raised cutting heights were less damaging to amphibians and invertebrates. A randomized, replicated, controlled trial from the UK found that raising mowing height on grasslands had no effect on numbers of foraging birds or invertebrates. One replicated controlled study found no difference in invertebrate abundance. One replicated study from the UK found that northern lapwing and common starling chicks had greater foraging success in shorter grass. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F138https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F138Fri, 18 Nov 2011 15:43:43 +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 refuges during harvest or mowing Three studies examined the effect of providing refuges for birds during harvest or mowing in France and the UK. One replicated study in France found evidence that providing refuges during mowing reduced contact between mowing machinery and unfledged quail and corncrakes. However one replicated controlled study and a review from the UK found that Eurasian skylark did not use nesting refuges more than other areas.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F147https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F147Sat, 14 Jan 2012 14:49:58 +0000Collected Evidence: Collected Evidence: Provide owl nest boxes (Tawny owl, Barn owl) Two studies from the UK (a before-and-after study and a controlled study) found that the provision of owl nest boxes in farm buildings maintained barn owl nesting and roosting activity and resulted in an increase in population density. A study from the Netherlands found that the barn owl population increased with increased availability of nest boxes. A replicated, controlled study in Hungary found that juvenile barn owls fledged from nest boxes were significantly less likely to be recovered alive than those reared in church towers. A replicated study from the UK investigating barn owl nest site use, found that the number of occupied nest sites and the proportion breeding decreased from 2001 to 2009, but were unaffected by the number of boxes.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F154https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F154Sat, 14 Jan 2012 15:38:54 +0000Collected Evidence: Collected Evidence: Provide nest boxes for birds Two studies (including one before and after study) from the Netherlands and the UK found that following the provision of nest boxes there was an increase in the number of Eurasian kestrel clutches and breeding tree sparrows. One replicated study from Switzerland found the number of Eurasian wryneck broods in nest boxes declined over five years whilst the number of Eurasian hoopoe broods increased. Eight studies from Finland, the Netherlands, Sweden, Switzerland and the UK (six were replicated) found that nest boxes in agricultural habitats were occupied by Eurasian kestrel, long-eared owl, common starling, tits Parus spp., tree sparrow, stock dove and jackdaw, and Eurasian wryneck and Eurasian hoopoe. Whilst two studies from the UK (a replicated, paired site study and a controlled study) found that carrion crows did not nest in artificial trees and tree sparrows showed a preference for nest boxes in wetland habitat, compared to those in farmland sites. Two replicated studies from Sweden found that nest success within boxes was related to the amount of pasture available and nest boxes positioned higher above the ground had higher occupancy, numbers of eggs and numbers of hatched young.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F155https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F155Sat, 14 Jan 2012 15:49:39 +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: Provide 'sacrificial' grasslands to reduce the impact of wild geese on crops All six studies from the UK (including four replicated, controlled trials) found that managing grasslands for geese increased the number grazing there. Two replicated, controlled studies found that fertilized and cut areas were grazed by more white-fronted geese or brent geese than control areas. A replicated, controlled trial found that re-seeded and fertilized wet pasture fields were used by more barnacle geese than control fields, and that fertilized areas were used less than re-seeded ones. A replicated, controlled study found that spring fertilizer application increased the use of grassland fields by pink-footed geese. A replicated study found that plots sown with white clover were preferred by dark-bellied brent geese compared to plots sown with grasses. However, four of the studies found that the birds were moving within a relatively small area (i.e. within the study site) and therefore the grasslands may not reduce conflict with farmers.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F641https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F641Mon, 15 Oct 2012 16:28:48 +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: Reduce chemical inputs in grassland management A total of 16 studies (including five reviews) investigated the effects of reducing inputs in permanent grasslands. Six studies from the Netherlands, Switzerland and the UK (including one review and four replicated studies of which one was also controlled and one a randomized and controlled before-and-after trial) found that stopping fertilizer inputs in permanent grassland resulted in an increase in plant species richness, reduced the rate of plant species loss and attracted a higher abundance or species richness of some or all invertebrates studied. One review from the Netherlands found that low fertilizer input grasslands favour common meadow bird species. One review found a study showing that densities of some invertebrates were higher in unfertilized plots compared with those receiving nitrogen inputs. Two replicated, controlled trials from the Czech Republic and the UK (one randomized) found that applying fertilizer to permanent grasslands reduced plant species richness or diversity and that the effects on plant communities were still apparent 16 years after the cessation of fertilizer application. Four studies from Ireland, the Netherlands and the UK (including two replicated trials of which one randomized and one controlled and a review) found that reducing fertilizer inputs on grassland had no clear or rapid effect on plant species richness. A review found no clear effect of reducing fertilizer inputs on the density of soil-dwelling invertebrates. One replicated study found that fertilizer treatment only affected seed production of a small number of meadow plants. One replicated study from the UK found lower invertebrate abundance on plots with reduced fertilizer inputs but the differences were not significant.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F694https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F694Sat, 01 Dec 2012 17:52:25 +0000
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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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