Collected Evidence: Collected Evidence: Sow uncropped arable field margins with a native wild flower seed mixFive replicated trials in the UK showed that uncropped field margins sown with wild flowers and subsequently mown support a higher abundance (and in three trials higher species richness) of foraging bumblebees than cropped field edges (all five trials), grassy margins (four trials) or naturally regenerated uncropped margins (three trials). One small trial recorded the same number of bee species on wildflower sown and naturally regenerated strips. Two trials demonstrated that perennial leguminous herbs in the seed mixtures are important forage sources for bumblebees, particularly for long-tongued species. One small replicated trial showed that common long-tongued bumblebee species (Bombus pascuorum and B. hortorum) strongly preferred plots of perennial wildflower seed mix over a mix of annual forage plants. We have captured no evidence on the effects of field margin management on solitary bees.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F19https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F19Thu, 20 May 2010 07:11:24 +0100Collected Evidence: Collected Evidence: Sow uncropped arable field margins with an agricultural nectar and pollen mixFive replicated trials in Europe (three controlled) have documented bumblebees foraging on field margins sown with an agricultural nectar and pollen seed mix. Four replicated trials showed that field margins sown with perennial leguminous flowering plants attract significantly more foraging bumblebees than naturally regenerated (two trials), grassy (four trials) or cropped (three trials) field margins. Three replicated trials showed that a mix of agricultural forage plants including legumes (all annual plants in one trial) attracts greater numbers of bumblebees than a perennial wildflower mix, at least in the first year. Three trials in the UK found evidence that margins sown with agricultural legume plants degrade in their value to bumblebees and would need to be re-sown every few years. We have captured no evidence on the effects of field margin management on solitary bees.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F18https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F18Thu, 20 May 2010 20:59:45 +0100Collected Evidence: Collected Evidence: Spray water to deter birds from pondsA replicated study from Sweden found that a rotating water spray deterred birds from fish ponds, but that birds often became used to the spray.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F255https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F255Wed, 18 Jul 2012 12:57:49 +0100Collected Evidence: Collected Evidence: Sowing roadside verges We captured no evidence for the effects of sowing roadside verges on bird populations. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action    Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F260https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F260Thu, 19 Jul 2012 13:21:32 +0100Collected Evidence: Collected Evidence: Start educational programmes for personal watercraft ownersA before-and-after trial in the USA found that rates of disturbance by personal watercraft decreased and reproductive success of common terns Sterna hirundo increased following a series of educational programmes aimed at recreational boat users.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F314https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F314Wed, 25 Jul 2012 18:11:40 +0100Collected Evidence: Collected Evidence: Sow rare or declining arable weeds Two studies from the UK (both replicated, controlled and randomized) found that the establishment of rare or declining arable weeds depended upon cover crop, cultivation, timing of cut and year or a combination of cultivation in autumn and herbicide treatment.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F642https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F642Tue, 16 Oct 2012 13:52:39 +0100Collected Evidence: Collected Evidence: Sterilize equipment when moving between amphibian sites We found no evidence for the effects of sterilizing equipment when moving between amphibian sites on the spread of disease between amphibian populations or individuals. Two randomized, replicated, controlled study in Switzerland and Sweden found that Virkon S disinfectant did not affect survival, mass or behaviour of common frog or common toad tadpoles or moor frog embryos or hatchlings. One of the studies found that bleach significantly reduced survival of common frog and common toad tadpoles.    Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F768https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F768Fri, 16 Aug 2013 16:21:14 +0100Collected Evidence: Collected Evidence: Sterilize equipment to prevent ranavirus We found no evidence for the effects of sterilizing equipment to prevent ranavirus on the spread of disease between amphibian individuals or populations. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.    Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F801https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F801Thu, 22 Aug 2013 14:46:02 +0100Collected Evidence: Collected Evidence: Sow tree seeds after wildfire Three studies (including one replicated, randomized, controlled study) in the USA examined the effect of sowing herbaceous plant seeds in burnt forest areas. One found it decreased the number and cover of native species and one found it decreased the density of tree seedlings. All three found no effect of seeding on total plant cover or species richness.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1236https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1236Fri, 03 Jun 2016 08:34:24 +0100Collected Evidence: Collected Evidence: Sow tree seeds One replicated, randomized, controlled, before-and-after study in Brazil found that sowing tree seeds increased the density and species richness of new trees.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1244https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1244Fri, 03 Jun 2016 11:02:33 +0100Collected Evidence: Collected Evidence: Sow seeds Five of six studies (including three replicated, randomized, controlled studies, one site comparison study and one controlled study) in the UK, South Africa, and the USA found that sowing seeds of shrubland species increased shrub cover. One of six studies in the UK found no increase in shrub cover. One replicated site comparison in the USA found in sites where seed containing Wyoming big sagebrush was sown the abundance of the plant was higher than in sites where it was not sown. One replicated, randomized, controlled study in the USA found that shrub seedling abundance increased after seeds were sown. One study in the USA found very low germination of hackberry seeds when they were sown. One replicated, randomized, controlled study in the USA found that the community composition of shrublands where seeds were sown was similar to that found in undisturbed shrublands. One randomized, controlled study in the UK found an increase in the cover of heathland plants when seeds were sown. One replicated, randomized, controlled study in South Africa found that sowing seeds increased plant cover. One replicated, randomized, controlled study in the USA found that areas where seeds were sown did not differ significantly in native cover compared to areas where shrubland plants had been planted. One controlled study in the USA found higher plant diversity in areas where seeds were sown by hand than in areas where they were sown using a seed drill. Two of three studies (one of which was a replicated, randomized, controlled study) in the USA found that sowing seeds of shrubland species resulted in an increase in grass cover. One randomized, controlled study in the UK found no changes in the cover of grasses or forbs. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1698https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1698Mon, 23 Oct 2017 11:05:08 +0100Collected Evidence: Collected Evidence: Sow seeds and plant individual plants One replicated, controlled study in the USA found that planting California sagebrush and sowing of seeds did not increase cover of native plant species compared to sowing of seeds, or planting alone. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1700https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1700Mon, 23 Oct 2017 11:14:02 +0100Collected Evidence: Collected Evidence: Spread clippings One randomized, controlled study in the UK found that the addition of shoots and seeds of heathland plants did not increase the abundance of mature plants for half of plant species. One randomized, controlled study in the UK found that the frequency of heather plants was not significantly different in areas where heather clippings had been spread and areas where they were not spread. One replicated, randomized, controlled study in the UK found an increase in the number of heather seedlings, but not of other heathland species. One randomized, controlled study in the UK found that the addition of shoots and seeds increased the number of seedlings for a minority of species. One replicated, randomized, controlled study in South Africa found that plant cover and the number of plant species did not differ significantly between areas where branches had been spread and those where branches had not been spread. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1701https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1701Mon, 23 Oct 2017 11:16:13 +0100Collected Evidence: Collected Evidence: Stabilize peatland surface to help plants colonize One study evaluated the effects of stabilizing the peatland surface (without planting) on peatland vegetation. The study was in a bog. Vegetation cover (1 study): One controlled, before-and-after study in a bog in the UK found that pegging coconut fibre rolls onto almost-bare peat did not affect the development of vegetation cover (total, mosses, shrubs or cottongrasses). Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1815https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1815Tue, 28 Nov 2017 08:43:30 +0000Collected Evidence: Collected Evidence: Specify a size range of capture for commercially fished species We found no studies that evaluated the effects of specifying a size range of commercially retained fish species on marine fish populations.  ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this intervention during our systematic journal and report searches. Therefore, we have no evidence to indicate whether or not the intervention has any desirable or harmful effects. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2737https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2737Tue, 02 Feb 2021 14:56:52 +0000Collected Evidence: Collected Evidence: Sow seeds of nurse plants One study examined the effects of sowing seeds of nurse plants on grassland vegetation. The study was in France. VEGETATION COMMUNITY (1 STUDY) Community composition (1 study): One replicated, controlled study in France found that sowing seeds of nurse plants reduced the similarity of the plant community to that of nearby intact steppe compared to areas where no seeds were sown. Overall richness/diversity (1 study): One replicated, controlled study in France found that sowing seeds of nurse plants did not change plant species richness and richness was lower than in nearby intact steppe. VEGETATION ABUNDANCE (1 STUDY) Overall abundance (1 study): One replicated, controlled study in France found that sowing seeds of nurse plants did not change vegetation cover compared to areas where no seeds were sown. VEGETATION STRUCTURE (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3401https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3401Fri, 25 Jun 2021 14:13:14 +0100Collected Evidence: Collected Evidence: Sow or plant nurse plants (alongside seeding/planting of grassland species) Four studies examined the effects of sowing or planting nurse plants alongside seeding/planting grassland species on grassland vegetation. Two studies were in Europe, one study was in the USA and one was in Kenya. VEGETATION COMMUNITY (1 STUDY) Community composition (1 study): One replicated, controlled study in Slovenia found that sowing a seed mix containing nurse species resulted in a community composition that was less similar to the target community when compared to sowing a seed mix that did not contain nurse species. Overall richness/diversity (1 study): One replicated, controlled study in Slovenia found that sowing a seed mix containing nurse species did not increase species richness compared to sowing a seed mix that did not contain nurse species. VEGETATION ABUNDANCE (1 STUDY) Grass abundance (1 study): One replicated, paired, controlled study in the USA found that sowing seeds of nurse plants alongside that of grassland species did not change grass abundance. Forb abundance (1 study): One replicated, paired, controlled study in the USA found that sowing seeds of nurse plants alongside that of grassland species did not change forb abundance. VEGETATION STRUCTURE (0 STUDIES) OTHER (2 STUDIES) Germination/Emergence (1 study): One replicated, controlled study in Spain found that sowing seeds under nurse plants increased seed germination. Survival (2 studies): One of two replicated, controlled studies (one of which was randomized and paired) in Kenya and Spain found that sowing seeds or planting under nurse plants increased survival of planted plants. The other study found that sowing seeds under nurse plants initially increased seedling survival, but there was no difference in survival after two to three years. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3402https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3402Fri, 25 Jun 2021 14:22:50 +0100Collected Evidence: Collected Evidence: Sow seeds of tree species in savanna One study examined the effects of sowing seeds of tree species in savanna on grassland vegetation. The study was in Brazil. VEGETATION COMMUNITY (0 STUDIES) VEGETATION ABUNDANCE (0 STUDIES) VEGETATION STRUCTURE (0 STUDIES) OTHER (1 STUDY) Germination/Emergence (1 study): One replicated study in Brazil found that sowing tree seeds in savanna resulted in germination of 52% of the tree seeds. Survival (1 study): One replicated study in Brazil found that after sowing tree seeds in savanna, 35% of the seeds produced seedlings that survived for more than two years. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3403https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3403Fri, 25 Jun 2021 14:32:10 +0100Collected Evidence: Collected Evidence: Sow seeds of parasitic species (e.g. yellow rattle) Six studies examined the effects of sowing seeds of parasitic species on grassland vegetation. Four studies were in the UK, one study was in Switzerland and one was in Belgium. VEGETATION COMMUNITY (6 STUDIES) Overall richness/diversity (6 studies): Five of six studies (including five controlled studies and one review) in the UK, Switzerland and Belgium found that sowing seeds of the parasitic plants yellow rattle, European yellow rattle or marsh lousewort increased plant species richness and/or diversity. The other study found that sowing yellow rattle seeds did not alter plant species richness. VEGETATION ABUNDANCE (3 STUDIES) Overall abundance (1 study): One review in the UK found that sowing seeds of the parasitic plant yellow rattle led to a decrease in total plant biomass in three of four studies. Characteristic plant abundance (1 study): One controlled study in Belgium found that sowing seeds of the parasitic plant marsh lousewort increased the abundance of six target plant species. Grass abundance (1 study): One replicated, controlled study in Switzerland found that sowing seeds of the parasitic plant European yellow rattle led to a decrease in grass cover. Forb abundance (1 study): One replicated, controlled study in Switzerland found that sowing seeds of the parasitic plant European yellow rattle did not alter the cover of forbs. VEGETATION STRUCTURE (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3404https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3404Fri, 25 Jun 2021 14:36:07 +0100Collected Evidence: Collected Evidence: Sow seeds at a higher density Six studies examined the effects of sowing seeds at a higher density on grassland vegetation. Four studies were in the USA, and one study was in each of the UK and Canada. VEGETATION COMMUNITY (2 STUDIES) Community composition (1 study): One replicated, randomized, controlled study in the UK found that sowing grass seeds at a higher density did not increase the similarity of the vegetation community to that of the target community. Forb richness/diversity (1 study): One replicated, randomized, paired, controlled study in the USA found that sowing seeds at a higher density increased forb species richness. VEGETATION ABUNDANCE (4 STUDIES) Sown/planted species abundance (1 study): One replicated, controlled study in the USA found that sowing seeds at a higher density did not alter the cover of sown plant species. Grass abundance (3 studies): One replicated, randomized, paired, controlled study in the USA found that sowing seeds at a higher density increased grass cover. Forb abundance (1 study): One replicated, randomized, paired, controlled study in the USA found that sowing seeds at a higher density increased forb cover. Tree/shrub abundance (1 study): One site comparison study in the USA found that sowing grass seeds at a higher density reduced the cover of native grassland shrubs. Individual plant species abundance (1 study): One replicated, controlled study in Canada found that sowing seeds at a higher density increased the cover of thickspike wheatgrass. VEGETATION STRUCTURE (0 STUDIES) OTHER (1 STUDY) Germination/Emergence (1 study): One replicated, randomized, paired, controlled study in the USA found that sowing seeds at a higher density increased the number of purple needlegrass seedlings. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3405https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3405Fri, 25 Jun 2021 14:49:43 +0100Collected Evidence: Collected Evidence: Sow seeds at start of growing season Three studies examined the effects of sowing seeds at the start of the growing season on grassland vegetation. Two studies were in the USA and one was in the UK. VEGETATION COMMUNITY (2 STUDIES) Overall richness/diversity (1 study): One replicated, randomized, controlled study in the USA found that sowing seeds in spring increased plant diversity compared to sowing in autumn. Sown/planted richness/diversity (1 study): One replicated, randomized, paired, controlled study in the UK found that sowing seeds in spring increased the number of sown species compared to sowing in autumn. VEGETATION ABUNDANCE (1 STUDY) Sown/planted species abundance (1 study): One replicated, randomized, paired, controlled study in the UK found that sowing seeds in spring increased the cover of sown grass and forb species compared to sowing in autumn. VEGETATION STRUCTURE (0 STUDIES) OTHER (1 STUDY) Germination/Emergence (1 study): One replicated, paired, controlled study in the USA found that sowing seeds in spring led to similar emergence of forb seedlings compared to sowing in winter. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3407https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3407Fri, 25 Jun 2021 15:03:30 +0100Collected Evidence: Collected Evidence: Sow seeds in part of site Three studies examined the effects of sowing seeds in part of a site on grassland vegetation. Two studies were in the USA and one was in the Czech Republic. VEGETATION COMMUNITY (2 STUDIES) Overall richness/diversity (1 study): One replicated study in the USA found that sowing seeds in part of a site resulted in an increase in plant species richness over time. Sown/planted species richness/diversity (1 study): One replicated, randomized, paired, controlled study in the Czech Republic found that sowing seeds in part of a site did not alter species richness for sown grass and herb species. VEGETATION ABUNDANCE (2 STUDY) Sown/planted species abundance (2 studies): One study in the USA found that after sowing seeds in part of a site, new patches of two of three sown plant species were recorded in unsown areas. One replicated, randomized, paired, controlled study in the Czech Republic found that sowing seeds in part of a site did not alter the cover of sown grass and herb species.  VEGETATION STRUCTURE (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3408https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3408Fri, 25 Jun 2021 15:14:50 +0100Collected Evidence: Collected Evidence: Sow seeds in prepared gaps within vegetation One study examined the effects of sowing seeds in prepared gaps within vegetation on grasslands. The study was in Hungary. VEGETATION COMMUNITY (0 STUDIES) VEGETATION ABUNDANCE (1 STUDY) Sown/planted species abundance (1 study): One replicated study in Hungary found that sowing seeds in large gaps within vegetation led to a greater cover of sown target plant species than sowing in smaller gaps.  VEGETATION STRUCTURE (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3409https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3409Fri, 25 Jun 2021 15:17:23 +0100Collected Evidence: Collected Evidence: Spray slurry of seed, mulch and water (‘hydroseeding’) Four studies examined the effects of spraying a slurry of seed, mulch and water (‘hydroseeding’) on grassland vegetation. Two studies were in Spain, one study was in the USA and one was in Italy. VEGETATION COMMUNITY (2 STUDIES) Overall richness/diversity (2 studies): One of two replicated, controlled studies (one of which was randomized and paired) in Spain and Italy found that hydroseeding with non-native seeds did not alter plant diversity in most cases. The other study found that hydroseeding increased plant species richness in one of two cases. VEGETATION ABUNDANCE (3 STUDIES) Overall abundance (2 studies): One of two controlled studies (one of which was replicated, randomized and paired) in Spain found that hydroseeding with non-native seeds increased overall plant cover in most cases. The other study found that hydroseeding did not alter vegetation cover. Sown/planted species abundance (1 study): One replicated, randomized, paired, controlled study in the USA found that hydroseeding increased the abundance of half of the sown plant species compared to drill seeding. VEGETATION STRUCTURE (1 STUDY) Height (1 study): One replicated, controlled study in Italy found that hydroseeding led to an increase in the height of herb species. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3412https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3412Fri, 25 Jun 2021 15:42:50 +0100Collected Evidence: Collected Evidence: Sterilize equipment to prevent spread of disease We found no studies that evaluated the effects on reptile populations of sterilizing equipment to prevent spread of disease. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated 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%2F3703https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3703Fri, 10 Dec 2021 19:03:54 +0000
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
For a full list of, and information about, our champions:
All Evidence Champions
About our champions, why and how to become one:
Become an Evidence Champion

This website uses Cookies

We use limited Cookies to run the site and to analyse our traffic (none for site vendors). By using this site, you will be providing your consent to our use of Cookies.

Accept & continue