Collected Evidence: Collected Evidence: Rear declining bumblebees in captivityWe have captured 22 trials from 13 countries documenting captive rearing of bumblebee colonies by confining mated queens alone (eight trials), with one or more bumblebee workers (seven trials), honey bee workers (one trial), male bumblebee pupae (three trials) or following anaesthetisation with CO2 (four trials). One trial found that over four years of artificial rearing, Bombus terrestris queens gradually decreased in weight. Three trials have tried to rear North American bumblebees now declining or thought to be declining. Two induced spring queens of the half-black bumblebee B. vagans to rear adults in captivity, one trial induced queen yellow-banded bumblebees B. terricola (attempted in all three trials) and red-belted bumblebees B. rufocinctus (only attempted in one trial) to rear adults in captivity. All three trials tried to rear the yellow bumblebee B. fervidus and in all cases the queens laid eggs but the larvae died before becoming adults. One trial found the same pattern for the rusty-patched bumblebee and the American bumblebee B. pensylvanicus. One study reports rearing the large garden bumblebee B. ruderatus, a Biodiversity Action Plan species in the UK. Two trials have reported laboratory rearing of a pocket-making bumblebee, the Neotropical B. atratus. Three replicated trials demonstrated that the pollen diet of captively reared bumblebees influences reproductive success. In one trial, buff-tailed bumblebee B. terrestris colonies fed on freshly frozen pollen produced larger queens that survived better and produced larger colonies themselves than colonies fed on dried, frozen pollen. Two replicated trials demonstrated that B. terrestris workers can produce more offspring when fed types of pollen with a higher protein content. Two replicated experiments showed that an artificial light regime of eight hours light, 16 hours darkness, can reduce the time taken for artificially reared queen B. terrestris to lay eggs, relative to rearing in constant darkness. We have captured two replicated trials examining the effect of different artificial hibernation regimes in B. terrestris. One showed that hibernation of queens at 4-5°C for 45 days enhanced egg-laying and colony formation rates, but hibernated queens produced smaller colonies than non-hibernated queens. The second showed that queens should weigh more than 0.6 g (wet weight) and be hibernated for four months or less to have a good chance of surviving.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F50https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F50Thu, 20 May 2010 20:22:36 +0100Collected Evidence: Collected Evidence: Provide artificial nesting sites for wildfowl Six studies from North America and Europe found that wildfowl populations increased with the provision of artificial nests, although one study from Finland found that there was no increase in the number of broods or chicks in areas with nest boxes. Twelve studies from North America investigated the success of nests in artificial nests with nine finding that success and productivity was high, sometimes higher than or similar to natural nests. Two studies found that success for some species in nest boxes was lower than for natural nests. Two studies investigated the impact of nest box location, finding that hidden nests had higher success and that nests over water were more successful than those in trees over land. Nineteen studies from across the world investigated occupancy rates of artificial nests, finding that rates varied from no use of 25 nest boxes in a single site in Indonesia to 100% occupancy across 20 sites in the USA with one study finding that nest boxes were used more than natural cavities. Two studies found that occupancy rates increased over time, whilst four studies found that occupancy rates appeared to be affected by design or positioning. Three studies from North America found that nest boxes could have other impacts on reproduction and behaviour, with common starlings Sturna vulgaris (a nest site competitor) avoiding some nest box designs; hidden nest boxes having lower intra-specific nest parasitism than easily visible boxes and female common eiders Somateria mollissima losing less weight over incubation if they were nesting in shelters, compared to birds nesting in the open, although they lost weight quicker after nesting.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F482https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F482Sat, 01 Sep 2012 14:23:12 +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: Head-start amphibians for release Twenty-two studies head-started amphibians from eggs and monitored them after release. Six of 10 studies (including five replicated studies) in Denmark, Spain, the UK and USA and a global review found that released head-started tadpoles, metamorphs or juveniles established breeding frog populations or increased populations of frogs or toads. Two found mixed results with breeding populations established in 12 of 17 studies reviewed or at two of four sites. Two found that head-started metamorphs or adults did not prevent a frog population decline or establish a breeding toad population. For five of the studies, release of captive-bred individuals, translocation or habitat management were also carried out. Nine of 10 studies (including nine replicated studies) in Australia, Canada, Europe and the USA found that head-started amphibians released as tadpoles, metamorphs or adults metamorphosed successfully, tended to survive the first season, winter or year or bred successfully. One found adult survival was 1–17% over four years and one found limited breeding following the release of adults. Four replicated studies in Australia, the UK and USA found that frog survival to metamorphosis and size at metamorphosis was greater and time to metamorphosis shorter in head-started compared to wild animals. One replicated study in Canada found that young head-started leopard frogs were smaller than those in the wild. One replicated study in Australia found that corroboree frog tadpoles released earlier had higher survival, but metamorphosed two weeks later than those released a month later. Three studies (including one replicated study) in the USA only provided results for head-starting in captivity. Two found that Houston toad eggs could be captive-reared to tadpoles, but only one successfully reared adults. Three studies (including two replicated studies) in Canada and the USA found that during head-starting, amphibian growth rate, size, stress levels and survival was affected by the amount of protein provided, housing density or enclosure location. One found that mass, stress levels and survival were not affected by the amount of food or habitat complexity.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F881https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F881Fri, 13 Sep 2013 13:02:34 +0100Collected Evidence: Collected Evidence: Use clearcutting to increase understory diversity Eight of 12 studies (including three replicated, randomized, controlled studies) in Belgium, Brazil, Canada, China, Germany, Israel, spain and the USA found that clearcutting increased the cover and species richness of understory plants. Two found it decreased the density and species richness, and two found no effect or mixed effects. Three of six studies (including five replicated, randomized, controlled studies) in Brazil, Canada and Spain found that clearcutting increased the density and species richness of young trees. One found it decreased new tree density and two found no effect or mixed effects depending on the tree species. Three of nine studies (including four replicated, randomized, controlled studies) in Australia, Brazil4, Canada, Japan and the USA found that clearcutting decreased density, species richness and diversity of mature trees. One study found it increased trees species richness .Six studies found no effect or mixed effects on tree density, size and species richness and diversity.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1222https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1222Mon, 23 May 2016 08:58:48 +0100Collected Evidence: Collected Evidence: Crop production: Grow cover crops in arable fieldsCrop yield (24 studies): Six replicated, controlled studies (five randomized) from Spain and the USA found lower cash crop yields in plots with winter cover crops, compared to plots without them, in some comparisons. Three replicated, randomized, controlled studies from Italy and the USA found higher cash crop yields in plots with winter cover crops, compared to plots without them, in some comparisons. Eight replicated, randomized, controlled studies from Italy and the USA found inconsistent differences in cash crop yields (sometimes higher, sometimes lower) between plots with or without cover crops. Seven controlled studies (six replicated, four randomized) from France, Israel, Spain, and the USA found no differences in cash crop yields between plots with or without cover crops. One replicated, randomized, controlled study from the USA found inconsistent differences in cash crop yields between plots with or without summer cover crops. Crop quality (6 studies): Three replicated, controlled studies (two randomized) from Italy, Spain, and the USA found no differences in cash crop quality between plots with or without winter cover crops. Two controlled studies (one replicated and randomized) from the USA found some differences in tomato quality between plots with winter cover crops or fallows. One replicated, randomized, controlled study from the USA found inconsistent differences in cash crop quality between plots with or without winter cover crops. Implementation options (9 studies): Eight studies from Italy, Spain, and the USA found higher cash crop yields in plots that had legumes as winter cover crops, compared to non-legumes. One study from the USA found higher cash crop yields in plots that had a mixture of legumes and grasses, compared to legumes alone.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1351https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1351Tue, 21 Mar 2017 11:54:49 +0000Collected Evidence: Collected Evidence: Crop production: Use reduced tillage in arable fieldsCrop yield (25 studies) Cereals (16 studies): Nine replicated, controlled studies from Egypt, France, Spain, and Turkey found higher cereal yields in plots with reduced tillage, compared to conventional tillage, in some or all comparisons. Three of these studies also found lower cereal yields in plots with reduced tillage, compared to conventional tillage, in some comparisons. Three replicated, randomized, controlled studies from Lebanon and Spain found lower cereal yields in plots with reduced tillage, compared to conventional tillage. Four replicated, controlled studies from Italy, Spain, and the USA found similar cereal yields in plots with reduced tillage or conventional tillage, in all comparisons. One replicated, randomized, controlled study from Spain found that crops failed in plots with conventional tillage, but not in plots with reduced tillage, in one of three comparisons. Fruits and vegetables (7 studies): Five replicated, randomized, controlled studies from Italy and the USA found higher fruit or vegetable yields in plots with reduced tillage, compared to conventional tillage, in some comparisons. Two of these studies also found lower fruit or vegetable yields in plots with reduced tillage, compared to conventional tillage, in some comparisons. Two replicated, controlled studies from Italy and the USA found similar fruit yields in plots with reduced tillage or conventional tillage, in all comparisons. All fruit or vegetable plots were irrigated, in contrast to most cereal or legume plots. Legumes (3 studies): One replicated, randomized, controlled study from Spain found lower legume yields in plots with reduced tillage, compared to conventional tillage, in one of four comparisons. Two replicated, controlled studies from Italy and Lebanon found similar legume yields in plots with reduced tillage or conventional tillage, in all comparisons. No studies found higher legume yields in plots with reduced tillage, compared to conventional tillage. Oilseeds (1 study): One replicated, randomized, controlled study from Spain found higher rapeseed yields in plots with reduced tillage, compared to conventional tillage. Crop residues (6 studies): Two replicated, randomized, controlled studies from Lebanon and Spain found lower straw yields in plots with reduced tillage, compared to conventional tillage, in some comparisons. One replicated, randomized, controlled study from Spain found higher straw yields in plots with reduced tillage, compared to conventional tillage, in some comparisons. Two replicated, controlled studies from Italy and Spain found similar straw yields in plots with reduced tillage or conventional tillage, in all comparisons. One replicated, randomized, controlled study from the USA found higher cover crop biomass in plots with reduced tillage, compared to conventional tillage. Crop quality (7 studies): One replicated, randomized, controlled study from Spain found that sunflower seeds had more oil, more monounsaturated fatty acid, and less polyunsaturated fatty acid in plots with reduced tillage, compared to conventional tillage. One replicated, controlled study from Italy found that wheat had a lower protein content in plots with reduced tillage, compared to conventional tillage. Two replicated, controlled studies from Italy and Turkey found similar seed weights in plots with reduced tillage, compared to conventional tillage. One replicated, randomized, controlled study from the USA found that lettuce or broccoli plants were larger in plots with reduced tillage, compared to conventional tillage, in some comparisons, but they were smaller in other comparisons. Implementation options (2 studies): One replicated, randomized, controlled study from Egypt found higher wheat yields in plots that were tilled at slower speeds. One replicated, randomized, controlled study from Turkey found higher wheat yields, but lower vetch yields, in plots with one type of reduced tillage (rototilling and disking), compared to another type (double disking).Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1359https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1359Fri, 05 May 2017 12:03:43 +0100Collected Evidence: Collected Evidence: Soil: Add compost to the soilOrganic matter (12 studies): Twelve replicated, controlled studies (ten randomized) from Italy, Spain, Syria, Turkey, and the USA found more organic matter in soils with added compost, compared to soils without added compost, in some or all comparisons. Nutrients (10 studies): Six replicated, controlled studies (five randomized) from Italy, Portugal, Spain, and Syria found more nutrients in soils with added compost, compared to soils without added compost, in some or all comparisons. Three replicated, randomized, controlled studies from Italy and the USA found inconsistent differences in nitrogen between soils with or without added compost. One replicated, randomized, controlled study from the USA found no differences in phosphorus between soils with or without added compost. Three replicated, randomized, controlled studies from Italy and Spain found similar pH levels in soils with or without added compost. Soil organisms (10 studies): Six replicated, controlled studies (five randomized) from Italy, Spain, and the USA found more microbial biomass in soils with added compost, compared to soils without added compost, in some or all comparisons. Two replicated, controlled studies from Italy and the USA found similar amounts of microbial biomass in soils with or without added compost. One replicated, randomized, controlled study from Italy found inconsistent differences in bacterial abundance between plots with or without added compost. Two replicated, randomized, controlled studies from Italy and Spain found differences in bacteria communities, in some comparisons. Soil erosion and aggregation (5 studies): Two replicated, controlled studies (one randomized) from Spain found less erosion of soils with added compost, compared to soils without added compost, in some or all comparisons. Four replicated, randomized, controlled studies from Spain and Turkey found that soils with added compost were more stable than soils without added compost, in some or all comparisons. Greenhouse gases (10 studies): Six replicated, controlled studies (five randomized) from Italy, Spain, and the USA found more greenhouse gas in soils with added compost, compared to soils without added compost, in some or all comparisons. Four replicated, randomized, controlled studies from Spain found no differences in greenhouse gas between soils with or without added compost. Implementation options (2 studies): One replicated, randomized, controlled study from Syria found more nitrogen in soils with compost added every two years, compared to soils with compost added every four years. One replicated, randomized, controlled study from Italy found inconsistent differences in bacteria abundance between soils with different amounts of added compost.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1362https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1362Mon, 08 May 2017 13:08:46 +0100Collected Evidence: Collected Evidence: Soil: Use organic fertilizer instead of inorganicOrganic matter (13 studies): Eight replicated studies (including one meta-analysis) from France, Italy, Spain, Turkey, and Mediterranean countries found more organic matter in soils with organic fertilizer, compared to inorganic fertilizer, in some comparisons. Five replicated, randomized, controlled studies from Greece, Spain, and the USA found similar amounts of organic matter in soils with organic or inorganic fertilizer. Nutrients (14 studies) Nitrogen (9 studies): Four replicated studies (three controlled, two randomized; one site comparison) from France, Italy, and Spain found more nitrogen in soils with organic fertilizers, compared to inorganic fertilizer, in some comparisons. Five replicated, randomized, controlled studies from Greece, Spain, and the USA found similar amounts of nitrogen in soils with organic or inorganic fertilizer. Ammonium (3 studies): Two replicated, randomized, controlled studies from Italy and Spain found more ammonium in soils with organic fertilizer, compared inorganic fertilizer, in some comparisons. One replicated, randomized, controlled study from Spain found similar amounts of ammonium in soils with organic or inorganic fertilizer. Nitrate (3 studies): One replicated, randomized, controlled study from Spain found less nitrate in soils with organic fertilizer, compared to inorganic fertilizer, in some comparisons. Two replicated, randomized, controlled studies from Portugal and Spain found similar amounts of nitrate in soils with organic or inorganic fertilizer. Phosphorus (5 studies): Three replicated, randomized, controlled studies from Italy and Spain found more phosphorus in soils with organic fertilizer, compared to inorganic fertilizer, in some or all comparisons. One replicated site comparison from France found less phosphorous in soils with organic fertilizer, in some comparisons. One replicated, randomized, controlled study from Spain found similar amounts of phosphorous in soils with organic or inorganic fertilizer. Potassium (6 studies): Three replicated, randomized, controlled studies from Italy and Spain found more potassium in soils with organic fertilizer, compared to inorganic fertilizer, in some comparisons. Three replicated studies (two controlled, one site comparison) from France and Spain found similar amounts of potassium in soils with organic or inorganic fertilizer. pH (6 studies): Four replicated studies (three randomized and controlled, one site comparison) from France, Italy, and Spain found similar pH levels in soils with organic or inorganic fertilizer. One replicated, controlled study from Italy found higher pH levels in soils with organic fertilizer, in some comparisons. One replicated, randomized, controlled study from Spain found lower pH levels in soils with organic fertilizer, in some comparisons. Soil organisms (7 studies) Microbial biomass (4 studies): Four replicated studies (three randomized and controlled, one site comparison) from France, Italy, and Spain found more microbial biomass in soils with organic fertilizer, compared to inorganic fertilizer, in some comparisons. Other soil organisms (4 studies): One replicated, randomized, controlled study from Spain found fewer bacteria in soils with organic fertilizer, compared to inorganic fertilizer, in one comparison. One replicated site comparison from France found fewer nematodes in plots with organic fertilizer, compared to inorganic fertilizer, in some comparisons. One replicated, randomized, controlled study from Spain found fewer mites in plots with organic fertilizer, compared to inorganic fertilizer. One replicated, randomized, controlled study from Italy found inconsistent differences in microbes between plots with organic or inorganic fertilizer. Soil erosion and aggregation (5 studies): Three replicated, randomized, controlled studies from Turkey and Spain found greater aggregation in soils with organic fertilizer, compared to inorganic fertilizer, in some or all comparisons. Two replicated, randomized, controlled studies from Spain and the USA found no difference in aggregation between soils with organic or inorganic fertilizer. Greenhouse gases (11 studies) Carbon dioxide (5 studies): Four replicated, randomized, controlled studies from Italy and Spain found higher carbon dioxide emissions from plots with organic fertilizer, compared to inorganic fertilizer, in some comparisons. One replicated, randomized, controlled study from Spain found similar carbon dioxide emissions from plots with organic or inorganic fertilizer. Methane (4 studies): Two replicated, randomized, controlled studies from Spain found that more methane was absorbed by soils with organic fertilizer, compared to inorganic fertilizer, in some comparisons. Two replicated, randomized, controlled studies from Spain found that similar amounts of methane were absorbed by soils with organic or inorganic fertilizer. Nitrous oxide (8 studies): Five replicated, randomized, controlled studies from Spain found similar nitrous oxide emissions from plots with organic or inorganic fertilizer. Three studies (including one meta-analysis and two replicated, randomized, controlled studies) from Spain, the USA, and Mediterranean countries found lower nitrous oxide emissions from plots with organic fertilizer, compared to inorganic fertilizer, in some comparisons. Implementation options (4 studies): One study from Spain found that plots with slurry absorbed methane, but plots with manure emitted methane. One study from Italy found more organic matter, nutrients, and microbial biomass in plots fertilized with compost, compared to manure. One meta-analysis found lower nitrous oxide emissions after adding solid organic fertilizer, but not liquid organic fertilizer, compared to inorganic fertilizer. One study found inconsistent differences in soil bacteria with a single or double application of organic fertilizer.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1366https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1366Tue, 09 May 2017 15:33:46 +0100Collected Evidence: Collected Evidence: Other biodiversity: Restore habitat along watercoursesAmphibians (1 study): One replicated site comparison from the USA found similar numbers of amphibian species in restored and remnant sites. Birds (8 studies): Two replicated site comparisons from Spain and the USA found similar numbers of bird species in restored and remnant sites. Two replicated site comparisons from the USA found fewer bird species in restored riparian sites, compared to remnant sites. One replicated site comparison from Spain found similar numbers of birds and bird species in restored contaminated sites and uncontaminated sites. One replicated site comparison from the USA found that an endangered bird nested in restored sites, and had similar nesting success in restored and remnant sites. One replicated site comparison from the USA found that bird populations increased with the area of restored habitat in the landscape, in some comparisons. One replicated site comparison from the USA found similar levels of nest parasitism in restored and remnant sites. Fish (1 study): One before-and-after site comparison from the USA found differences in fish communities, before and after changing river flow. Invertebrates (3 studies): One replicated site comparison from the USA found fewer native ants, but similar numbers of invasive ants, in restored sites, compared to remnant sites. One before-and-after site comparison from the USA found similar numbers of freshwater invertebrates in restored and reference sites, after restoration. One replicated, before-and-after study from the USA found more invertebrates and invertebrate species in plots with added gravel, compared to plots without added gravel, in some comparisons. One replicated before-and-after study from France found relatively more alien species after restoring river flow. Mammals (2 studies): Two replicated site comparisons from the USA found similar numbers of mammal species in restored and remnant sites. Plants (11 studies) Abundance (6 studies): Four replicated site comparisons from Spain and the USA found lower plant cover in restored sites, compared to remnant sites. One of these studies also found higher cover of exotic plants, but another one did not. One replicated, paired site comparison from the USA found similar numbers of flowers in restored and remnant sites. One replicated site comparison from the USA found more seeds, but fewer native seed, in orchards next to restored riparian habitats, compared to orchards next to remnant habitats. One replicated site comparison from the USA found similar exotic plant cover in remnant and restored forests. Diversity (6 studies): Two replicated studies from the USA found fewer native plant species in restored forests, compared to remnant forests. One of these studies also found more exotic species, but another one did not. One replicated site comparison from the USA found more plant species in restored sites, compared to remnant sites. One replicated, paired site comparison from the USA found similar numbers of flower species in restored and remnant sites. One replicated site comparison from the USA found fewer seed species and native seed species in orchards next to restored riparian habitats, compared to remnant riparian habitats. One controlled study from the USA found different plant communities in restored and unrestored habitats. Survival (2 studies): One replicated study from the USA found that about one-third of planted willows survived for one year. One site comparison from the USA found that some species survived after planting, as part of riparian restoration, but others did not. Habitat suitability (1 study): One replicated site comparison from the USA found that vegetation at one of five sites met the criteria for Bell’s Vireo nesting habitat. Size (1 study): One replicated site comparison from the USA found smaller elderberry plants in restored sites. Reptiles (1 study): One replicated site comparison from the USA found similar numbers of reptile species in remnant and restored sites. Implementation options (7 studies) Plants (3 studies): One study from the USA found more tree, shrub, vine, and perennial species, higher canopy cover, and higher native tree cover, in older restored plots, compared to younger restored plots, but this study also found fewer annual plant species, lower vegetation cover, lower annual forb cover, and lower grass cover. One study from the USA found an increase in native species and overstorey cover in restored sites, over time, but it found similar numbers of species and overstorey cover in sites planted at different densities. One study from the USA found that willow cuttings planted on the stream bottom had a higher survival rate than those planted on the streambank or terrace. Birds (3 studies): Three studies from the USA found more birds or bird species in older restored plots, compared to younger restored plots. One of these studies also found that the populations of some bird species increased with tree-planting density. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1416https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1416Fri, 19 May 2017 09:54:10 +0100Collected Evidence: Collected Evidence: Conduct veterinary screens of animals before reintroducing/translocating them One before-and-after study in Brazil found that most reintroduced golden lion tamarins did not survive over seven years, despite undergoing pre-release veterinary screens, alongside other interventions. One study in Brazil found that most reintroduced black lion tamarins that underwent veterinary screens, alongside other interventions, survived over four months. One before-and-after study in Malaysia found that 90% of reintroduced Müller's Bornean gibbons did not survive despite undergoing veterinary screens, alongside other interventions. One controlled study in Indonesia found that reintroduced Bornean agile gibbons that underwent veterinary screens, alongside other interventions, behaved similarly to wild gibbons. Two studies, including one controlled, in Malaysia and Indonesia found that most translocated orangutans that underwent veterinary screens, along with other interventions, survived translocation and the first three months post-translocation. Four studies, including three before-and-after studies, in Liberia, the Republilc of Congo and Guinea found that most reintroduced chimpanzees that underwent veterinary screens, alongside other interventions, survived over 1-5 years. One before and after study in Uganda found that a reintroduced chimpanzee repeatedly returned to human settlements after undergoing pre-release veterinary screens, alongside other interventions. Five studies, including four before-and-after studies, in Belize, French Guiana, Madagascar, Congo and Gabon found that most reintroduced or translocated primates that underwent veterinary screens, alongside other interventions, survived at least four months or increased in population size. Five studies, including four before-and-after studies, in French Guiana, Madagascar, South Africa and Vietnam found that most reintroduced or translocated primates were assumed to have died post-release despite undergoing pre-release veterinary screens, alongside other interventions. One controlled study in Kenya found that a population of translocated olive baboons were still surviving 16 years after translocation when veterinary screens were applied alongside other interventions. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1553https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1553Thu, 19 Oct 2017 20:15:52 +0100Collected Evidence: Collected Evidence: Allow primates to adapt to local habitat conditions for some time before introduction to the wild Two studies in Brazil and Thailand found that reintroduced primate populations were smaller after 12-17 months and one study in Belize found primate populations increased five years after allowing individuals to adapt to local habitat conditions before introduction into the wild, alongside other interventions. One study found that a reintroduced population of black howler monkeys had a birth rate of 20% after they were allowed to adapt to local habitat conditions before introduction into the wild, along with other interventions. Seven studies in Brazil, Madagascar, Malaysia, French Guiana, South Africa found that a minority of primates survived for at least 15 weeks to 12 years after allowing them to adapt to local habitat conditions before introduction into the wild, along with other interventions. Four studies in Belize, Brazil, Gabon, South Africa found that the majority of primates survived for at least four to 12 months. One study in Vietnam found that half of reintroduced pygmy slow lorises survived for at least two months. Two before-and-after studies in Gabon and the Republic of Congo found that a majority of western lowland gorillas survived for nine months to four years after allowing them to adapt to local habitat conditions before introduction into the wild, along with other interventions. Three studies in Liberia and the Congo found that a majority of chimpanzees survived for at least three to five years after allowing them to adapt to local habitat conditions before introduction into the wild, along with other interventions. One before-and-after study in Uganda found that a chimpanzee repeatedly returned to human settlements after allowing it to adapt to local habitat conditions before introduction into the wild, along with other interventions. A study in Indonesia found that Sumatran orangutans that were allowed to adapt to local habitat conditions before introduction performed less well than individuals that were directly released into the forest, alongside other interventions. One controlled study in Indonesia found that after being allowed to adapt to local habitat conditions a pair of introduced Bornean agile gibbons had a similar diet to wild gibbons. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1564https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1564Fri, 20 Oct 2017 10:08:36 +0100Collected Evidence: Collected Evidence: Release translocated/captive-bred mammals in family/social groups Twenty-six studies evaluated the effects of releasing translocated or captive-bred mammals in family or social groups. Eleven were in the USA, seven were in South Africa and one was in each of Poland, Zimbabwe, along the USA–Canada border, Russia, Italy, Canada, China and India. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (22 STUDIES) Abundance (4 studies): A study in the USA found that a translocated population of Rocky Mountain bighorn sheep released in groups increased at a similar rate to that of a population newly established through natural recolonization. A replicated, controlled study in the USA found that after translocating black-tailed prairie dogs in social groups to areas with artificial burrows, colonies increased in size over four years. A replicated study in Canada found that following translocation of elk, most of which had been kept in holding pens in groups, numbers increased at two of four sites. A study in the USA found that following the release of captive-reared bighorn sheep in groups, the overall population declined over 14 years. Reproductive success (11 studies): A study in the USA found that captive-reared bighorn sheep released in groups had similar population recruitment rates compared to wild-reared sheep. A replicated, paired study in the USA found that black-tailed prairie dogs translocated as family groups had higher reproductive success than those translocated in non-family groups. A replicated study in the USA found that translocated gray wolves had similar breeding success when adult family groups were released together from holding pens or when young adults were released directly into the wild. Six of eight studies (one replicated) in Poland, Russia, South Africa, the USA and the USA–Canada border found that when translocated and/or captive-bred animals were released in social or family groups, cheetahs, European bison, lions, African wild dogs, most European beavers and some swift foxes reproduced successfully. One study found that one of two translocated Cape buffalo groups released after being held in a holding pen formed a single herd and reproduced, while the other scattered and escaped the reserve. One study found that no Gunnison's prairie dogs reproduced during the first year. Survival (19 studies): One of three studies (one controlled, before-and-after) in the USA found that when translocated or captive-bred animals were released in family or social groups, captive-reared bighorn sheep had similar survival compared to wild-reared sheep, whereas two found lower survival compared to wild white-tailed deer and San Joaquin kit foxes. Three replicated studies (one controlled, one paired) in the USA found that when translocated as a social or family group, black‐tailed prairie dogs had higher and white-tailed deer and gray wolves had similar survival rates to those translocated as unrelated groups or individuals. Ten studies (one replicated) in Poland, Russia, Italy, South Africa, the USA, USA–Canada border, China and India found that when translocated and/or captive-bred animals were released in social or family groups, a population of Przewalski’s horses and European bison persisted 5-11 years, lions, most swift foxes and European beavers and half or more cheetahs survived for at least one year, and one-horned rhinoceroses and over half of Gunnison's prairie dogs and Eurasian badgers survived at least 1-6 months. Three studies in the USA and South Africa found that when translocated or captive-bred animals were released in family or social groups (some provided with artificial refuges and/or supplementary food), most Mexican wolves did not survive over eight months and all rock hyraxes died within 90 days. A study in South Africa found that translocated and captive-bred African wild dogs released in family groups into fenced reserves had high survival rates. Condition (1 study): A study in China found that following the release of captive-bred Przewalski’s horses in groups, the population had a lower genetic diversity than two captive populations. BEHAVIOUR (4 STUDIES) Behaviour change (4 studies): Two replicated, controlled (one before-and-after) studies in the USA found that when translocated as a social or family group, white-tailed deer had similar average dispersal distances and Utah prairie dogs had similar release site fidelity and post-release behaviour compared to those translocated as unrelated groups. One found that deer translocated together did not stay together, whether they had previously been part of the same social group or not. A study in Zimbabwe found that a translocated lion family joined with immigrant lions and formed a new pride. A study in South Africa found that translocated lions that were released in groups that had already been socialised and formed into prides, established stable home ranges. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2463https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2463Tue, 02 Jun 2020 12:17:05 +0100Collected Evidence: Collected Evidence: Remove/control non-native mammals Twenty-five studies evaluated the effects on non-controlled mammals of removing or controlling non-native mammals. Twenty-one studies were in Australia, and one was in each of France, the UK, Equador and the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (24 STUDIES) Abundance (21 studies): Ten of 18 controlled, before-and-after or site comparison studies, in Australia, found that after controlling red foxes, abundances, densities or trapping frequencies increased for rock-wallaby spp., eastern grey kangaroo, woylie,, brush-tail possum, tammar wallaby, chuditch and quenda. Seven studies found mixed results with increases in some species but not others, increases followed by declines or increases only where cats as well as foxes were controlled. The other study found no increase in bush rat numbers with fox control. One of three replicated, before-and-after studies (including two controlled studies), in Australia, France and Ecuador, found that control of invasive rodents increased numbers of lesser white-toothed shrews and greater white-toothed shrews. One study found that Santiago rice rat abundance declined less with rodent control and one found mixed results, with increased numbers of short-tailed mice at one out of four study sites. Survival (1 study): A replicated, controlled study in Australia found that controlling red foxes increased survival of juvenile eastern grey kangaroos. Occupancy/range (3 studies): Three studies (two before-and-after, one controlled), in the UK and Australia, found that after controlling non-native American mink, red foxes and European rabbits, there were increases in ranges or proportions of sites occupied by water vole, common brushtail possum, long-nosed potoroo and southern brown bandicoot and four native small mammal species. BEHAVIOUR (1 STUDY) Behaviour change (1 study): A before-and-after study in the USA found that following removal of feral cats, vertebrate prey increased as a proportion of the diet of island foxes. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2504https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2504Thu, 04 Jun 2020 15:58:03 +0100Collected Evidence: Collected Evidence: Install tunnels/culverts/underpass under roads Twenty-five studies evaluated the effects on mammals of installing tunnels, culverts or underpass under roads. Eight studies were in the USA, four were in Australia, four were in Canada, two were in Spain, one each was in Germany, the Netherlands and South Korea and three were reviews with wide geographic coverage. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (3 STUDIES) Survival (3 studies): A study in South Korea found that road sections with higher underpass density did not have fewer wildlife-vehicle collisions. A review found that most studies recorded no evidence of predation of mammals using crossings under roads. A controlled, before-and-after, site comparison study in Australia found that overwinter survival of mountain pygmy-possums increased after an artificial rocky corridor, which included two underpasses, was installed. BEHAVIOUR (23 STUDIES) Use (23 studies): Seventeen of 20 studies (including seven replicated studies and two reviews), in the USA, Canada, Australia, Spain, the Netherlands, and across multiple continents, found that crossing structures beneath roads were used by mammals whilst two studies found mixed results depending on species and one study found that culverts were rarely used as crossings by mammals. One of the studies found that crossing structures were used by two of four species more than expected compared to their movements through adjacent habitats. A controlled, before-and-after, site comparison study in Australia found that an artificial rocky corridor, which included two underpasses, was used by mountain pygmy-possums. A replicated study in Germany found that use of tunnels by fallow deer was affected by tunnel colour and design. A study in the USA found that a range of mammals used culverts, including those with shelves fastened to the sides. Behaviour change (1 study): A controlled, before-and-after, site comparison study in Australia found that after an artificial rocky corridor, which included two underpasses, was installed, dispersal of mountain pygmy-possums increased. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2514https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2514Fri, 05 Jun 2020 10:17:32 +0100Collected Evidence: Collected Evidence: Use a different hook type Twenty-five studies examined the effect of using a different hook type on marine fish populations. Nine studies were in the Atlantic Ocean (Portugal, South Africa, USA, Brazil, Portugal, Iceland), six studies were in Pacific Ocean (New Zealand, Japan, Costa Rica, Hawaii, Fiji) and two studies were in the Mediterranean Sea (Spain, Italy). One study was in each of the Barents Sea (Norway), the Denmark Strait (Greenland), the Coral Sea (Australia) and the Strait of Gibraltar (Spain/Morocco). Four studies were reviews (worldwide, Atlantic and Pacific Oceans). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (10 STUDIES) Survival (10 studies): Four of seven replicated, controlled studies in the Atlantic Ocean, Pacific Ocean and Coral Sea and two of three worldwide systematic reviews, found that using different hook types in longline or recreational fisheries, including sizes, styles and other modifications to hooks, reduced the incidence of fish hook injuries (associated with higher post-release mortality), and reduced the capture mortality of some species of unwanted sharks and rays and non-target billfish species, compared to conventional hooks or other hook types. The other four studies found that using a different hook type did not reduce the post-release mortality of young sea breams, or the capture mortality of sharks species and non-target fish species, but did reduce the incidence of deep-hooking in some cases. BEHAVIOUR (0 STUDIES) OTHER (23 STUDIES) Reduction of unwanted catch (20 studies): Eight of 16 replicated studies (13 controlled, one randomized) in the Atlantic Ocean, Pacific Ocean, Barents Sea, Mediterranean Sea, Denmark Strait and Coral Sea, found that using a different hook type, including different sizes, styles and hook modifications, reduced the unwanted catch in longline and recreational hook fisheries of non-commercially targeted and targeted fish species, small non-target fish species, overall fish catch, overall discarded bony fish catch but not sharks and rays, undersized haddock, two of three unwanted fish species, non-target sharks and rays and non-target rays and sailfish, compared to standard hooks or hooks of other types. Seven studies found that changing hook type did not reduce the unwanted catch of young or non-target fish species, unwanted sharks and rays, unwanted blue shark, unwanted roughhead grenadier or non-target pelagic stingray and silky shark, compared to standard or other hook types. The other study found that catch rates of young groupers, and non-target fish and shark species varied with hook design, and larger hooks caught fewer non-target fish species overall, but more undersized grouper and sharks compared to other hook types. Four global systematic reviews found that hook style did not affect the unwanted catch of billfish species, sharks and rays or sharks, compared to standard styles. Improved size-selectivity of fishing gear (3 studies): Two of three replicated studies in the Atlantic Ocean and Strait of Gibraltar, found that increasing hook sizes improved the size-selectivity (by increasing the average catch length) of hottentot and black spot seabream compared to smaller hook sizes. The other study found that a different hook size improved size selectivity for two of five commercially targeted fish species and was also affected by bait size. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2698https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2698Tue, 08 Dec 2020 15:46:56 +0000Collected Evidence: Collected Evidence: Use a square mesh instead of a diamond mesh codend in a trawl net Twenty-six studies examined the effects of using a square mesh instead of a diamond mesh codend in a trawl net on marine fish populations. Five studies were in the North Atlantic Ocean (Canada, Portugal, USA), four were in the Aegean Sea (Greece, Turkey), three were in the Mediterranean Sea (Spain) and the Tasman Sea (Australia), two studies were in each of the English Channel (UK), the Adriatic Sea (Italy) and the South Pacific Ocean (Australia, Chile), and one study was in each of the Greenland Sea (Iceland), the North Pacific Ocean (USA), the Bristol Channel (UK), the Kattegat and the Skagerrak (Denmark) and the Coral Sea (Australia).  COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Survival (2 studies): One of two replicated, paired, controlled studies in the Aegean Sea and Bristol Channel found that the short-term survival of two of six fish species was higher after escaping through a square mesh compared to a diamond mesh codend. The other study reported that skate caught in a square mesh codend had a higher overall survival likelihood than those caught in a diamond mesh codend. BEHAVIOUR (0 STUDIES) OTHER (25 STUDIES) Reduction of unwanted catch (16 studies): Ten of 16 replicated, controlled studies (including five paired, three randomized and three randomized and paired) in the Greenland Sea, Aegean Sea, Atlantic Ocean, Tasman Sea, Pacific Ocean, Mediterranean Sea, English Channel, Bristol Channel and Coral Sea, found that square mesh codends reduced the unwanted (non-target or non-marketable/discarded) catches of all fish species monitored, young individuals of half or most commercially targeted fish, total unwanted catch (fish and invertebrates), and discarded fish in deeper but not shallower fishing areas, compared to diamond mesh codends; and two of those studies also found that there was a variable effect on unwanted catch between individual fish species/groups. Four studies found no reduction in catches of unwanted small rockfish and flatfish, three of four commercially important bottom fish species, total unwanted catch (fish and invertebrates), or the total number of unwanted species (fish and invertebrates), compared to diamond mesh codends. One study found that square mesh codends retained more fish overall than diamond mesh but varied for individual species by fish shape and size. One study found that unwanted fish catch depended on codend mesh size as well as configuration (square or diamond). Two of the studies, where square mesh codends had no or a varied effect, also found that size selectivity increased with increases in mesh size for both square and diamond mesh codends. Improved size-selectivity of fishing gear (14 studies): Six of 14 replicated, controlled studies (including three paired, one randomized and one randomized and paired) in the Atlantic Ocean, Mediterranean Sea, Adriatic Sea, Aegean Sea, English Channel, Pacific Ocean, Tasman Sea and the Kattegat and Skagerrak, found that using a square mesh codend in a trawl net (bottom and pelagic) improved size selectivity for silver hake, horse mackerel, European hake, axillary seabream, poor cod, greater forkbeard, blue whiting, discarded fish and three of four commercially targeted fish, compared to diamond mesh codends. Five studies found no difference in size selectivity between square and diamond mesh codends for Atlantic mackerel, long rough dab, yellowtail scad and striped seapike, rockfish and flatfish, and three of four commercially important bottom fish species. The other three studies found that the effect of square mesh instead of diamond mesh codends varied with fish body shape (round or flat), and for three of three and five of five roundfish species size selectivity was improved, but not for one flatfish. Two of the studies, where square mesh codends had either no or a varied effect, also found that size selectivity increased with increases in mesh size for both square and diamond mesh codends. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2714https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2714Fri, 01 Jan 2021 14:39:22 +0000Collected Evidence: Collected Evidence: Rehabilitate and release injured, sick or weak marine and freshwater mammals Twenty-seven studies evaluated the effects of rehabilitating and releasing injured, sick or weak marine and freshwater mammals. Nine studies were in the North Atlantic Ocean (USA, UK, France), six studies were in the North Pacific Ocean (USA), four studies were in the Gulf of Mexico (USA), two studies were in each of the North Sea (the Netherlands) and the Gulf of Maine (USA), and one study was in each of the Indian River Lagoon (USA), Bohai Bay (China), The Wash estuary (UK), water bodies in Florida (USA), El Dorado Lake (Peru), and the Gulf of California (Mexico). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (26 STUDIES) Reproductive success (1 study): One replicated study in the North Pacific Ocean found that more than a quarter of rehabilitated and released Hawaiian monk seals reproduced. Survival (26 studies): Twenty-one studies (including two controlled studies, four replicated studies and one review) in the North Atlantic Ocean, the Gulf of Maine, the Gulf of Mexico, the North Pacific Ocean, the Indian River Lagoon, The Wash estuary, water bodies in Florida, El Dorado Lake, and the Gulf of California found that 10–100% of dolphins, porpoises, whales, seals, sea lions and manatees released after rehabilitation in captivity survived during post-release monitoring periods, which ranged in length from three days to five years. Five studies (including one replicated study) in the North Sea, the North Atlantic Ocean, Bohai Bay and the North Pacific Ocean found that two of three harbour porpoises, 152 of 188 grey seal pups, a common seal, a west Pacific finless porpoise and 14 of 35 California sea lions were successfully rehabilitated and released but survival after release was not reported. One controlled study in the North Pacific Ocean found that at least a quarter of California sea lions treated for toxic algae poisoning and released back into the wild died or had to be euthanized. BEHAVIOUR (3 STUDIES) Behaviour change (3 studies): Two of three controlled studies in the North Atlantic Ocean, the North Pacific Ocean and The Wash estuary found that a harbour porpoise and six harbour seals that were rehabilitated and released had similar movements and/or behaviours to wild mammals. The other study found that California sea lions treated for toxic algae poisoning and released travelled further from the shore, spent less time diving or hauled out and made shorter, shallower dives than wild sea lions without poisoning. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2925https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2925Mon, 08 Feb 2021 16:57:11 +0000Collected Evidence: Collected Evidence: Restore/create freshwater marshes or swamps (specific action unclear) Twenty-five studies evaluated the effects, on vegetation, of restoring/creating freshwater marshes or swamps using unclear or incompletely described actions. Twenty-three studies were in the USA. Two were in Canada. Two of the studies used the same set of wetlands. VEGETATION COMMUNITY Community types (1 study): One replicated, site comparison study in the USA reported that created wetlands had greater coverage of herbaceous vegetation after 7–8 years than natural wetlands, but lower coverage of forest and shrubby vegetation. Community composition (17 studies): Four replicated, site comparison studies in the USA found that the overall plant community composition in created freshwater wetlands differed from the community in natural wetlands, after 1–21 years. Two replicated, site comparison studies in the USA and Canada reported mixed effects of freshwater marsh restoration/creation on overall algal or plant community composition, depending on the habitat and use of mining waste during creation. Of four replicated, site comparison studies in the USA and Canada, three reported lower quality vegetation in restored/created wetlands than in natural wetlands, but one reported similar vegetation quality in created and natural wetlands. Two replicated, site comparison studies in the USA found that created marshes developed a plant community characteristic of similar wetness to natural marshes within 4–21 years – but in one study, this was only true for created marshes >10 years old. Seven replicated studies in the USA simply quantified the composition, quality or wetness of the plant community up to 22 years after wetland restoration/creation. Overall richness/diversity (17 studies): Eleven replicated studies, in the USA and Canada, compared overall plant richness/diversity in created/restored and natural/unmanaged freshwater wetlands. Five of the studies found that created/restored wetlands typically had similar plant taxonomic richness to natural/unmanaged wetlands. Three of the studies reported lower species richness in created than natural wetlands after 1–18 years. Two of the studies reported higher species richness in created than natural wetlands after 1–21 years. The final study reported mixed effects of marsh creation on plant species richness, depending on the vegetation zone and use of mining waste during creation. Two of the studies reported identical results for plant diversity as for richness (similar or greater in created vs natural wetlands) but one study found that the effect of management on plant diversity depended on the timing of drawdown. Six replicated studies in the USA simply quantified overall plant species richness and/or diversity over 1–16 years after wetland restoration/creation. Native richness/diversity (3 studies): Of two replicated, site comparison studies of freshwater wetlands in the USA, one found that restored/created wetlands contained more native plant species than natural wetlands after 1–11 years. The other found that restored wetlands contained fewer native plant species than natural wetlands after 2–8 years. One replicated study of swamp restoration sites in the USA simply quantified native plant richness over 1–8 years after intervention. VEGETATION ABUNDANCE Overall abundance (7 studies): Six replicated studies, all in the USA, compared overall vegetation abundance in created/restored and natural wetlands. Four of the studies found that created/restored freshwater wetlands contained less vegetation (cover or biomass) than natural wetlands after 1–18 years. Two of the studies found that created and natural fresh/brackish/saline wetlands contained a similar amount of vegetation (overall cover and density; wetland plant cover) after >1 year. One of these studies reported that restored wetlands had lower vegetation cover than natural marshes – but this reflected management goals. One replicated study in the USA simply quantified total vegetation cover and biomass 3–10 years after marsh creation. Herb abundance (2 studies): One replicated, site comparison study in the USA reported that created wetlands had greater overall cover of herb species, after 7–8 years, than natural wetlands. One replicated study in the USA simply quantified herb biomass in wetland restoration sites after 7–22 years. Tree/shrub abundance (1 study): One replicated study in the USA simply quantified the density of woody vegetation in wetland restoration sites after 7–22 years. Algae/phytoplankton abundance (1 study): One replicated, site comparison study in the USA found that ≤15-year-old restored freshwater marshes contained a similar phytoplankton biomass to natural marshes. Individual species abundance (9 studies): Nine studies quantified the effect of this action on the abundance of individual plant species. For example, one replicated, site comparison study in the USA found that created and natural freshwater marshes supported a similar abundance of pickerelweed Pontederia cordata after 1–11 years. VEGETATION STRUCTURECollected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3190https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3190Wed, 07 Apr 2021 07:27:57 +0100Collected Evidence: Collected Evidence: Raise water level to restore/create freshwater marshes from other land uses Twenty-six studies evaluated the effects, on vegetation, of raising the water level to restore/create freshwater marshes from other land uses or habitat types. Twenty-one studies were in the USA. There was one study in each of Israel, the UK, China, Luxembourg and Canada. Eight studies used sites from a common set of 62 restored prairie potholes in the Midwest USA. Five studies monitored the effects of one river dechannelization project in Florida. VEGETATION COMMUNITY Overall extent (5 studies): One replicated, paired, before-and-after, site comparison study in the USA reported that damming a stream reduced the area of emergent vegetation on the floodplain. Two before-and-after studies of a floodplain in the USA reported that after dechannelizing a river to raise the water level, the area of emergent herbaceous vegetation increased. Two studies in the USA and Luxembourg simply quantified coverage of wetland vegetation 1–6 years after raising the water table (sometimes along with other interventions). Community types (9 studies): Nine studies quantified the effect of this action on specific types of marsh vegetation. For example, one before-and-after study of a floodplain in the USA reported greatly increased coverage of wet prairie plant communities after dechannelizing a river to raise the water table, but only slightly increased coverage of mixed herbaceous/shrubby wetland communities. Five studies in the USA and Luxembourg simply quantified the number, abundance or extent of wetland plant communities present 1–6 years after raising the water table (typically along with other interventions). Community composition (8 studies): Three replicated, site comparison studies (two also paired) in the USA evaluated the effects of rewetting farmed depressions (along with planting cover crops in/around them). One of these studies reported that restored wetlands contained a different overall plant community to natural wetlands after 5–7 years. One study reported that the plant community composition differed more between restored and natural wetlands than amongst restored or natural wetlands. The final study found that restoration increased vegetation quality after ≥10 years, but not to the level of natural wetlands. Two site comparison studies in China and the USA reported that the plant community became more similar to natural wetlands over 6–15 years after raising the water level – in terms of species composition or overall wetness. Three replicated studies in the USA simply quantified the plant community composition for up to three years after rewetting farmland (sometimes along with other interventions). Overall richness/diversity (12 studies): Four replicated, site comparison studies (two also paired) of one set of historically farmed depressions in the USA reported that restored wetlands (rewetted, along with planting cover crops in/around the sites) had lower overall plant species richness than nearby natural wetlands, after 1–7 years. Two before-and-after, site comparison studies of historical wetlands on a floodplain in the USA reported that raising the water level reduced overall plant species richness in the following six years. One site comparison study of lakeshore marshes in China reported that the total plant species richness in former paddy fields with breached weirs was similar to a nearby natural marsh, after 2–15 years. Five studies (two replicated) in the USA and Israel simply quantified overall plant species richness and/or diversity between three months and 19 years after raising the water table (sometimes along with other interventions). Characteristic plant richness/diversity (1 study): One before-and-after, site-comparison study of a floodplain in the USA reported that dechannelizing a river to raise the water level had no clear effect on the richness of wetland-characteristic plant species in the following six years. VEGETATION ABUNDANCE                                                                             Overall abundance (9 studies): Three before-and-after, site-comparison studies of historical wetlands on a floodplain in the USA reported that dechannelizing a river to raise the water level reduced overall vegetation cover in the following 6–9 years. One site comparison study in China reported that vegetation biomass in former paddy fields with breached weirs was similar to a nearby natural marsh, after 2–15 years. In contrast, one replicated, site comparison study in the USA found that vegetation cover in rewetted, formerly farmed depressions (also planted with cover crops) was lower than in nearby natural wetlands, after 5–7 years. Four studies (two replicated) in the USA and the UK simply quantified vegetation abundance between three months and six years after raising the water table (sometimes along with other interventions). Characteristic plant abundance (4 studies): Three before-and-after studies (two also site comparisons) of historical wetlands on a floodplain in the USA reported that dechannelizing a river to raise the water level increased the abundance of habitat- and/or wetland-characteristic plant species in the following 6–9 years. One study in the UK simply quantified the abundance of wet meadow plant species present 3–5 years after rewetting farmland (and introducing grazing). Bryophyte abundance (1 study): One replicated, site comparison study in the USA found that the frequency of bryophytes in (the wettest parts of) marshes rewetted 34 years previously was not significantly different from their frequency in (the wettest parts of) nearby natural marshes. Individual species abundance (11 studies): Eleven studies quantified the effect of this action on the abundance of individual plant species. For example, one replicated, site comparison study of freshwater marshes in the USA reported that Kneiff’s feathermoss Leptodictyum riparium was the most abundant plant species in marshes rewetted 34 years previously and nearby natural marshes. One before-and-after study of historical wetlands on a floodplain in the USA reported that after dechannelizing a river to raise the water level, some plots became dominated by a non-native grass species. VEGETATION STRUCTURECollected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3198https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3198Fri, 09 Apr 2021 07:44:56 +0100Collected Evidence: Collected Evidence: Translocate adult or juvenile reptiles: Tortoises, terrapins, side-necked & softshell turtles Twenty-six studies evaluated the effects of translocating tortoises, terrapins, side-necked & softshell turtles on their populations. Sixteen studies were in the USA, two were Global and one was in each of Italy, the Seychelles, Madagascar, Cameroon, Egypt, China, Jordan and France. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (24 STUDIES) Abundance (4 studies): One replicated study and one of two global reviews reported that three of eight translocations of turtles resulted in established populations and 15 of 47 reptile translocations resulted in stable or growing populations (review included both wild-caught and captive bred animals). The other review (both wild-caught and captive bred animals) reported that one of five translocation of tortoises and snapping turtles was unsuccessful and four had unknown outcomes. One study in the Seychelles found that 47% of translocated Aldabra giant tortoises were found 12 years after releaser. Reproductive success (5 studies): One global review reported that successful reproduction was found in three of five translocations of tortoises and snapping turtles (review included both wild-caught and captive bred animals). Two of three studies (including one replicated, randomized study) in the USA, Italy and Madagascar reported successful reproduction in translocated populations of gopher tortoises and radiated tortoises. The other study reported no evidence of reproduction for three years following a translocation of European pond turtles. One replicated study in the USA found that translocated female Agassiz’s desert tortoises bred successfully following release, but all hatchlings were sired by resident tortoises, not translocated males. Survival (16 studies): Two of four controlled studies (including one replicated study) in the USA found that translocated eastern box turtles and Eastern painted turtles had lower survival than resident turtles. The other two studies found that translocated desert tortoises and musk turtles had similar survival to that of resident turtles. One replicated study in the USA found that translocated gopher tortoises released into temporary enclosures had similar survival compared to head-started tortoises also released into temporary enclosures over four years. Five of 11 studies (including two replicated, controlled studies) in the USA, Italy, Cameroon, Egypt, China, Jordan and France reported that 69–100% of 3–40 translocated individuals survived for monitoring periods of one month to two years. Four studies reported that 19–43% of 15–109 translocated individuals survived for 2–3 years. The other two studies reported that 0–1% of 15 and 249 translocated individuals survived for up to a year. Condition (3 studies): One controlled study in the USA found that translocated Eastern painted turtles lost more body mass than resident turtles. One controlled, before-and-after, replicated study in the USA found that translocated desert tortoises had similar stress levels compared to resident tortoises. One study in the USA found that one translocated Blanding’s turtle grew over a two-year period following release. BEHAVIOUR (9 STUDIES) Use (2 studies): Two replicated studies (including one controlled study) in the USA found that one of 13 translocated gopher tortoises returned to its point of capture, and no Agassiz’s desert tortoises translocated >5 km returned to their point of capture. Behaviour change (7 studies): Two of six studies (including three replicated, controlled studies) in the USA and Jordan found mixed effects on the movement of translocated red-eared slider turtles in spring or autumn and on the movement and home range size of translocated eastern box turtles compared to residents. Two studies found that four measures of behaviour of translocated musk turtles and home range size of translocated spur-thighed tortoises were similar to residents. One study found that translocated gopher tortoises moved more and had larger home ranges than resident tortoises. The other study found that after ephemeral ponds dried up, translocated Eastern painted turtles did not move to new ponds whereas resident turtles did. One replicated study in France found that the home ranges of translocated European pond turtles were smaller in the year after release compared to the year they were released. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3708https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3708Mon, 13 Dec 2021 11:22:03 +0000Collected Evidence: Collected Evidence: Breed reptiles in captivity: Tortoises, terrapins, side-necked & softshell turtles Twenty-eight studies evaluated the effects of breeding tortoises, terrapins, side-necked & softshell turtles in captivity. Twelve studies were in the USA, four were in the Seychelles, two were in Madagascar, two were in an unknown location and one was in each of the Galápagos, Germany, Austria, Jersey, Italy, India, China and Myanmar. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (28 STUDIES) Abundance (5 studies): Four studies (including one replicated study) in Madagascar, the Seychelles and the USA reported that captive breeding programmes produced 255 ploughshare tortoises, 40 and 140 giant tortoises, 75 juvenile radiated tortoises and 94 Madagascar big-headed turtle hatchlings. One study also reported that the captive population grew each year. One replicated study in Myanmar reported that the number of Burmese star tortoise hatchlings produced in captivity increased from 168 to over 2,000 over eight years. Reproductive success (24 studies): Eighteen studies (including one replicated, controlled, before-and-after study) in the USA, the Galápagos, Germany, Austria, the Seychelles, Italy, India, China and an unknown location reported that females produced 0–25 clutches of 1–26 eggs, 65–78 eggs each/year or a total of 10–170 eggs. Three of these studies reported hatching success of 52–100%, four reported hatching success of 23–71%, three reported hatching success of 0–66%, 0–81% or 0–100% and six reported hatching success of 0–43% or 0–3 hatchings/clutch. One other study from the Seychelles reported that 0–75% of eggs from one of two mud turtle species hatched successfully. One of the studies also found that three of five eggs produced by a captive-bred tortoise hatched successfully. Two studies in Jersey and the Seychelles reported that only 3 Malagasy Flat-tailed tortoise eggs and 3–18 mud turtle eggs hatched successfully over 11–12 years. One study in Madagascar reported that most Madagascar big-headed turtle eggs laid in captivity were infertile. One study in the USA reported that hatching success of 2nd generation captive desert tortoises was 20–83%, whereas success for 3rd generation tortoises was 0–43%. One study in the USA found that hatching success for captive Bourret’s box turtle eggs was higher when incubated at 26–27°C compared to 28–29°C. Survival (7 studies): Three studies (including one replicated study) in the USA, Austria and an unknown location reported that 2–4 captive-bred tortoises or turtles survived for at least 28 weeks to two years. One replicated study in Italy reported that all captive-bred spider tortoises survived to adult size. Two studies in the USA and Jersey reported that 25–30% of captive-bred tortoises died within 12–18 months. One study in the Seychelles reported that 70% of captive-bred mud turtles died during hatching BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Offspring sex ratio (1 study): One study in the USA reported that a captive breeding programme of radiated tortoises produced 67 females and eight males. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3746https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3746Tue, 14 Dec 2021 11:18:05 +0000Collected Evidence: Collected Evidence: Cease grazing on grassland to allow early succession Twenty-six studies evaluated the effects on butterflies and moths of ceasing grazing on grassland to allow early succession. Five studies were in the UK, four were in each of Germany and the USA, three were in each of Sweden and Finland, two were in each of Spain and the Czech Republic, and one was in each of Switzerland, Europe and Israel. COMMUNITY RESPONSE (14 STUDIES) Community composition (3 studies): Two replicated, site comparison studies in the Czech Republic and Germany found that the community composition of butterflies and moths in grasslands which had been abandoned for >5 years or an unspecified length of time was similar to grasslands managed by grazing or mowing (results not distinguished). One replicated, controlled, before-and-after study in Spain found that after grazing and mowing management was abandoned, over 6 years the butterfly community became dominated by generalist species, and species with fewer generations/year. Richness/diversity (12 studies): Six of nine replicated studies (including one randomized, controlled study, one paired, site comparison, and seven site comparisons) in Germany, the USA, Finland, Sweden and the Czech Republic found that grasslands which had been not been grazed for >5 years, or an unspecified length of time, in one case with burning, had a similar species richness of butterflies and day-flying, burnet or all moths to grasslands grazed by cattle, horses and cattle or a mix of livestock (in two studies grazing and mowing were not distinguished) or grazed with cattle and burned. One of these studies also found that grasslands abandoned for 5–15 years had a greater species richness than grasslands grazed by sheep. A further two studies found that grasslands which had been abandoned for >5–20 years or many years had a lower species richness of butterflies than grazed grasslands (in one study grazing and mowing were not distinguished). The other study found that butterfly species richness was higher in grasslands where grazing ceased 2–9 years ago than those abandoned >10 years ago or those currently grazed. Three replicated studies (including one randomized, controlled study and two site comparison studies) in Switzerland, Germany and the UK found that grasslands which had been abandoned for 4, 5–10 or >10 years had a higher species richness of butterflies and day-flying moths and nocturnal moths than extensively grazed, recently abandoned or commercially grazed grasslands. Two of these studies also found that grassland abandoned for 4 or 5–10 years had a similar species richness of butterflies and day-flying moths and all moths to grassland lightly grazed by cattle or sheep/sheep and cattle. POPULATION RESPONSE (24 STUDIES) Abundance (24 studies): Six of 20 replicated studies (including one paired, controlled, before-and-after study, three randomized controlled studies, and 15 site comparison studies) in Germany, the USA, the UK, Switzerland, Finland, Sweden, Spain, the Czech Republic and Israel found that grasslands which had been abandoned for 1-25 years had a higher abundance of Scotch argus, butterflies and day-flying moths, nocturnal moths, caterpillars, and of small insects including caterpillars, than grasslands grazed by goats, sheep and/or cattle. Two of these studies only found a difference compared to grazing at commercial/intensive, not low, densities. Four of the studies found that grasslands which had been abandoned for two weeks, 5–20 years or an undetermined time had a lower abundance of butterflies and spring webworm caterpillars than grasslands grazed by cattle or a mix of livestock (in two studies grazing and mowing were not distinguished). A further four of the studies found that grasslands which had been abandoned for 5-15 years had a similar abundance of butterflies, burnet moths, day-flying moths and meadow neb moth caterpillars to grasslands grazed by sheep, horses and cattle or a mix of livestock. A further four of the studies found that in grasslands which had been abandoned for >10 years, many years or an unspecified number of years, and in one case with burning, abundance or density was mixed depending on butterfly and moth species compared to grasslands grazed by cattle or unspecified grazers or grazed with cattle and burned. The other study found that butterfly density was higher in grasslands where grazing ceased 2–9 years ago than those abandoned >10 years ago or those currently grazed. Two replicated studies (including one controlled, before-and-after study and one site comparison study) in Spain and Germany found that grasslands which had been abandoned for 1–6 years or an unspecified time period had a higher abundance of woodland and hedgerow butterflies and burnet moths, but a lower abundance of grassland or farmland species, than grasslands managed by grazing and/or mowing (results not distinguished). Two studies also found that the large blue and silver-studded blue went extinct in some abandoned meadows. One replicated, site comparison study in Sweden found that grasslands which were ungrazed for the year had a lower abundance of clouded Apollo butterflies than lightly grazed grasslands, but a higher abundance than heavily grazed grasslands. One review in Europe reported that ceasing grazing on grassland benefitted six out of 67 butterfly species of conservation concern. BEHAVIOUR (3 STUDIES) Use (3 studies): One replicated, paired, site comparison study in Germany found that grassland which had been abandoned for >5 years had a similar occurrence of hoary bell moth caterpillars to grassland grazed by sheep. One replicated, site comparison study in the UK found that a similar proportion of grasslands which had been abandoned for one year, and grazed grasslands, contained >20 marsh fritillary caterpillar webs. One replicated, site comparison study in Spain found that grizzled skipper and painted lady occurred less frequently, but small pearl-bordered fritillary occurred more frequently, in meadows which had been abandoned for at least 1–2 years than in meadows managed by grazing or mowing (results not distinguished). Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3956https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3956Sun, 14 Aug 2022 10:36:11 +0100Collected Evidence: Collected Evidence: Plant grass buffer strips/margins around arable or pasture fields Twenty-six studies evaluated the effects on butterflies and moths of planting grass margins around arable or pasture fields. Seventeen were in the UK, two were in each of Sweden, the Netherlands and the USA, and one was in each of China, France and Italy. COMMUNITY RESPONSE (15 STUDIES) Richness/diversity (15 studies): One of two replicated, controlled studies in the UK found that 2-m grass margins had a greater species richness of butterflies than cropped field edges, but 6-m grass margins did not. The other study found that the species richness of butterflies was similar in grass margins and cropped field edges. Five replicated, site comparison studies (including one paired study) in the USA, the UK and Italy found that wider grass margins (up to 6 m wide) had a greater species richness or diversity of butterflies, macro-moths and micro-moths than narrower or conventional width margins, although one of these studies found that the species richness of macro-moths was similar in wide and conventional grass margins. Three of five replicated studies (including three randomized, controlled studies, one controlled study, and one site comparison study) in the UK and Sweden found that floristically enhanced grass buffers or wildflower strips had a greater species richness of butterflies than standard grass margins. The other two studies found that farms with floristically enhanced margins (along with other enhanced agri-environment scheme (AES) options) had a similar species richness of butterflies and moths to farms with standard grass margins (along with basic AES options) and farms with no grass margins or other AES options. One site comparison study in Sweden found that grass margins sown with legumes or a clover and grass ley had a higher species richness of butterflies and moths than uncultivated margins, but less than a species-rich pasture. One replicated study in the Netherlands found that the species richness of butterflies increased over time after the establishment of grass margins. One replicated, randomized, controlled, before-and-after study in the USA found that disking or burning grass margins did not affect the species richness of butterflies. POPULATION RESPONSE (22 STUDIES) Abundance (21 studies): Three of four replicated, controlled studies in the UK found that grass margins had a higher abundance of butterflies than cropped field edges. The other study found that the abundance of gatekeepers on grass margins increased over four years after they were sown, but was only higher than cropped field edges at one of three farms after 2–4 years. Three of seven replicated, site comparison studies (including two paired studies) in the USA and the UK found that wider grass margins (up to 6 m wide) had a higher abundance of habitat-sensitive butterflies, macro-moths and micro-moths than narrower or conventional width margins. Two of these studies, and the other four studies, found that the abundance of disturbance-tolerant butterflies, macro-moths generally, and pale shining brown moths specifically, was similar in wide and conventional grass margins. Four replicated studies (including two randomized, controlled studies, one controlled study, and one site comparison study) in the UK and Sweden found that floristically enhanced grass buffers or wildflower strips had a higher abundance of butterflies than standard grass margins, uncultivated margins or margins sown with cereal crop. Two replicated, randomized, controlled studies in the UK found that farms with floristically enhanced margins (along with other enhanced agri-environment scheme (AES) options) had a higher abundance of some butterflies and micro-moths, a similar abundance of macro-moths, but a lower abundance of other butterflies, than farms with standard grass margins (along with basic AES options) and farms with no grass margins or other AES options. One site comparison study in Sweden found that grass margins sown with legumes or a clover and grass ley had a higher abundance of butterflies and moths than uncultivated margins or a species-rich pasture. Two replicated, before-and-after studies (including one randomized, controlled study) in the Netherlands and the USA found that mowing, disking or burning grass margins did not affect the abundance of butterflies and moths generally, or diamondback moths specifically, but that disking increased the abundance of disturbance-tolerant butterflies. One replicated, paired, site comparison study in the UK found that field margins had a similar abundance of butterfly and moth caterpillars to beetle banks established in the middle of fields. Survival (1 study): One site comparison study in China found that the survival of marsh fritillary caterpillars in grass margins around lightly cultivated fields was lower, but survival of egg clusters similar, to in uncultivated, grazed meadows. BEHAVIOUR (2 STUDIES) Use (2 studies): One replicated, site comparison study in China found that grass margins around lightly cultivated fields were more likely to be occupied by marsh fritillary eggs and caterpillars than uncultivated, grazed meadows. One replicated, paired, site comparison study in France found that meadow brown butterflies used grass margins in a similar way to meadows. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3982https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3982Thu, 18 Aug 2022 11:38:08 +0100
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What Works in Conservation

What Works in Conservation provides expert assessments of the effectiveness of actions, based on summarised evidence, in synopses. Subjects covered so far include amphibians, birds, mammals, forests, peatland and control of freshwater invasive species. More are in progress.

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