Conservation Evidence: Evidence Data

Collected Evidence: Collected Evidence: Replace honey-hunting with apiculture One study reported that a programme to enhance take-up of stingless beekeeping in southern Mexico increased the number of managed colonies in the area. Five trials contributed to scientific improvement of stingless beekeeping methods. Two controlled trials showed that either brewer's yeast (one trial) or a mix with 25% pollen collected by honey bees Apis mellifera (one trial) can be used as a pollen substitute to feed Scaptotrigona postica in times of pollen scarcity. A study on the island of Tobago found a wooden hive design with separate, different-shaped honey and brood chambers allowed honey to be extracted without damaging the brood. One trial showed that 50 g of comb with mature pupae is enough to start a new daughter colony of S. mexicana. One trial found brood growth was higher in traditional log hives than in box hives with internal volumes exceeding 14 litres, and recommended smaller box hives. We have captured no clear evidence about whether these activities help conserve bees or enhance native bee populations. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F33https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F33Thu, 20 May 2010 06:29:24 +0100Collected Evidence: Collected Evidence: Leave arable field margins uncropped with natural regenerationFour replicated trials in the UK have found more bumblebees (and more bee species in two trials) foraging on uncropped field margins than on cropped margins. One small unreplicated trial found similar bee species richness on a naturally regenerated margin as on margins sown with wildflowers. A small replicated trial found that neither abundance nor diversity of bumblebees were higher on naturally regenerated margins than on cropped margins. Two trials note that the value of naturally regenerated uncropped field margins is based on thistle species considered to be pernicious weeds requiring control. Two trials found that the value of naturally regenerated uncropped field margins for bees was not consistent from year to year. We have captured no evidence on the effects of field margin management on solitary bees. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F20https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F20Thu, 20 May 2010 16:57:57 +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: Leave uncut strips of rye grass on silage fields Two reviews and two replicated controlled trials from the UK found that leaving uncut strips of rye grass on silage fields resulted in benefits to birds including increased numbers. One of these studies found that whilst seed-eating birds preferred rye grass cut once only, birds that fed on different food resources such as insect-eaters showed more variable results with some preferring plots cut two or more times. One replicated controlled randomized study from the UK found no difference in ground beetle abundance and diversity between cut and uncut silage field headlands in the first two years of the experiment, but higher species diversity in uncut plots in the third year. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F132https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F132Mon, 14 Nov 2011 22:28:34 +0000Collected Evidence: Collected Evidence: Create scrapes and pools Three studies from Sweden and the UK (including two site comparisons one of which was replicated) found that the creation of scrapes and pools provided habitat for a range of plant, invertebrate or bird species and resulted in increased aquatic macroinvertebrate diversity. One of these studies found constructed pools supported locally or nationally scarce species of plant and water beetle. A study in Sweden found that a combination of large surface area, high shoreline complexity and shallow depth resulted in increased bird, bottom-dwelling invertebrate and aquatic plant diversity. However there were fewer fish species than in natural wetlands. Two replicated studies from Ireland and the UK (one controlled paired study and a site comparison) found that bird visit rates were higher but invertebrate numbers varied in ditch-fed paired ponds compared with dry controls and total macroinvertebrate and beetle richness did not differ between artificial and natural ponds, although communities did differ. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F153https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F153Sat, 14 Jan 2012 15:30:46 +0000Collected Evidence: Collected Evidence: Legally protect habitats Four studies (two replicated) from Europe found population increases following habitat protection, more positive population trends in protected habitats, compared with outside, or with increases amounts of protected habitats. A literature review reported that a large number of cranes (Gruidae) of seven species used nature reserves in China, whilst a replicated, randomised and controlled study from Argentina found that some guilds of birds were found at higher species richnesses in protected forests, some at higher densities, and that some showed no differences. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F158https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F158Tue, 15 May 2012 13:48:22 +0100Collected Evidence: Collected Evidence: Protect bird nests using electric fencing One before-and-after study from the UK found an increase in tern numbers after the erection of an electric fence, whilst a study from the USA found an increase in the number of nests. Five studies from the USA found higher survival or productivity at wader or seabird colonies with electric fencing, compared to areas without fencing, although one study found that hatching rates were no different, whilst nesting success was only higher in one of two years. One study from the USA found lower predation by mammalian predators inside electric fence exclosures, whilst predation by birds was higher. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F188https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F188Wed, 13 Jun 2012 16:59:40 +0100Collected Evidence: Collected Evidence: Create beetle banks A small UK study found that a site with beetle banks had increasing populations of rare or declining species, although several other interventions were used on this site. A literature review from the UK found that grey partridge Perdix perdix populations were far larger on sites with beetle banks and other interventions than on other farms. Two replicated studies from the UK also investigated population-level effects: one found that no bird species were strongly associated with beetle banks; the second found no relationship between beetle banks and grey partridge population density trends. A UK literature review found that two bird species nested in beetle banks and that some species were more likely to forage in them than others. A study in the UK found that one of two species used beetle banks more than expected. The other used them less than other agri-environment options. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F217https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F217Tue, 17 Jul 2012 12:04:26 +0100Collected Evidence: Collected Evidence: Use netting to exclude fish-eating birds Two replicated studies from Germany and the USA found that netting or closely-spaced string barriers reduced losses of fish or deterred fish-eating birds from fish ponds. A review concluded that excluding birds was an effective way to reduce damage. A series of tests in the Netherlands found that netting or nylon lines over ponds did not prevent birds from landing, but did alter behaviour, whilst a before-and-after study from the USA found that fewer great blue herons Ardea Herodias landed at fish ponds with netting, but that they stayed longer. Two replicated studies from Germany and Israel found that some birds became entangled in netting or closely-spaced string barriers over fish ponds. The Israeli study found that dark, small meshed netting entangled fewer birds than other netting types. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F248https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F248Wed, 18 Jul 2012 12:00:45 +0100Collected Evidence: Collected Evidence: Use education programmes and local engagement to help reduce persecution or exploitation of species Five out of six studies from across the world found increases in bird populations or decreases in mortality following education programmes. In all but one case, education was one of several interventions employed. A replicated before-and-after study from Canada also found that there was a significant shift in local peoples’ attitudes to conservation and exploited species following educational programmes. One study from Venezuela found no evidence for decreases in yellow-shouldered parrot Amazona barbadensis poaching following an educational programme in local schools. The authors argue that the benefits would probably be seen later in the project. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F274https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F274Thu, 19 Jul 2012 18:28:35 +0100Collected Evidence: Collected Evidence: Mow or cut natural grasslands Of six studies, two replicated and controlled studies from the USA found higher densities of birds or nests on mown grasslands, compared to unmanaged or burned areas. Two controlled studies from the USA, one replicated, found lower nesting or population densities of some species, on mown grasslands compared to unmown areas. Two replicated and controlled studies found no significant differences in nesting densities or community composition between mown and unmown areas. One study from the USA found that grasshopper sparrow nesting success was higher on mown areas than grazed areas of grassland. A replicated controlled study from the USA found that ducks had similar nesting success on cut and uncut areas. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F338https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F338Sat, 28 Jul 2012 15:41:22 +0100Collected Evidence: Collected Evidence: Manage water level in wetlands Of six studies, one replicated, controlled study from the USA found that bird diversity was affected by maintaining water levels at different levels. A study from the USA found that ducks were more abundant when high water levels were maintained on a wetland site. Geese were more abundant when lower levels were maintained. Three studies from the USA and Canada, two replicated, found that different species showed preferences for different water levels in wetlands. A replicated study from the UK found that great bitterns established territories earlier when deep water levels were maintained, but this had no effect on productivity. A review from Spain found that management successfully maintained water near a greater flamingo nesting area, but the effects of this were not measured. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F355https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F355Sun, 29 Jul 2012 16:49:45 +0100Collected Evidence: Collected Evidence: Create scrapes and pools in wetlands and wet grasslands Of six studies captured, four before-and after studies from the UK and North America found that the use of sites, or the breeding population of birds on sites, increased following the creation of ponds and scrapes or was higher in areas with ditch-fed ponds. A study from the USA found that dabbling ducks used newly-created ponds in large numbers, although other species preferred older ponds. Songbirds did not appear to be affected by pond-creation. A replicated site from the UK found that northern lapwing chicks foraged in newly created wet features and that chick condition was higher in sites with a large number of footdrains. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F359https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F359Sun, 29 Jul 2012 17:26:31 +0100Collected Evidence: Collected Evidence: Restore or create coastal and intertidal wetlands All six studies found, from the USA and UK, found that target bird species used restored or created wetlands. Two found that numbers and/or diversity were at least as high as in natural wetlands, one that numbers were higher than in unrestored sites. Three found that bird numbers on wetlands increased over time. Two studies from the UK found that songbirds and waders decreased following wetland restoration, whilst a study from the USA found that songbirds were more common on unrestored sites than restored wetlands. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F367https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F367Tue, 07 Aug 2012 13:15:07 +0100Collected Evidence: Collected Evidence: Remove vegetation to create nesting areas Two out of six studies found that the number of waders and terns nesting in an area increased following the removal of vegetation, and another found that a tern colony moved to an area prepared by removing vegetation. Two of these studies used multiple interventions at once. One study found a decrease in colony size after several interventions, including vegetation control. A study from the UK found that gulls and terns nested in an area cleared of vegetation and a controlled study from Puerto Rico found that although no terns nested in plots cleared completely of vegetation, more nested in partially-cleared plots than in uncleared plots. A before-and-after study from Canada found that tern nesting success was higher after plots were cleared of vegetation and other interventions were used. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F505https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F505Thu, 06 Sep 2012 14:00:49 +0100Collected Evidence: Collected Evidence: Provide supplementary food for gulls, terns and skuas to increase reproductive success Four studies of three experiments from Europe and Alaska found that providing supplementary food increased fledging success or chick survival in two gull species, although a study from the UK found that this was only true for one island, with abnormally low breeding success. A second island with higher success was not affected by feeding. Two of the experiments fed parent birds and one fed the chicks directly. One study from the Antarctic found no effect of feeding parent skuas on productivity. One study from Alaska found increased chick growth when parents were fed; one study from the Antarctic found no increase in chick growth. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F525https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F525Sat, 08 Sep 2012 13:37:48 +0100Collected Evidence: Collected Evidence: Provide supplementary food for gamebirds to increase adult survival Two European studies found increased numbers of grey partridge Perdix perdix in fed areas, compared to unfed areas. In one study there was no change in the overall population in the study area, in the second there was an increase. One cross-over study from the USA found that northern bobwhites Colinus virginianus had higher overwinter survival in fed areas, one found lower survival and a literature review found no overall effect of feeding. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F544https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F544Sun, 16 Sep 2012 09:01:06 +0100Collected Evidence: Collected Evidence: Provide supplementary food for nectar-feeding songbirds to increase adult survival Two studies from Australia and New Zealand found that ten species of honeyeaters and stitchbirds Notiomystis cincta readily used feeders supplying sugar solutions, with seasonal variations varying between species and stitchbirds spending more time foraging for insects when food was supplied. A series of ex situ trials using southern African birds found that most species tested showed a preference for sucrose solutions over glucose or fructose. One study found that sunbirds and sugarbirds only showed such a preference at low (equimolar) concentrations. Two more studies found that two species showed preferences for sucrose when comparing 20% (by weight) solutions, although a third species did not show this preference. All species rejected solutions with xylose (a natural sugar in nectar) added. A final study found that sucrose preferences only became apparent at equicalorific concentrations high enough for birds to subsist on. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F553https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F553Sat, 22 Sep 2012 20:11:36 +0100Collected Evidence: Collected Evidence: Release captive-bred individuals into the wild to restore or augment wild populations of cranes Four studies of five release programmes from the USA and Russia, from a total of eight programmes, found that released cranes had high survival or bred in the wild. Two studies from two release programmes in the USA found low survival of captive-bred eggs fostered to wild birds, compared with wild eggs, or a failure to increase the wild flock size. A worldwide review found that releases of migratory species only tended to be successful if birds were released into existing flocks, with higher success for non-migratory populations. One study from the USA found that birds released as sub-adults had higher survival than birds cross-fostered to wild birds. One study from the USA found that 73% of all mortalities occurred in the first year after release. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F621https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F621Sun, 14 Oct 2012 14:04:41 +0100Collected Evidence: Collected Evidence: Release captive-bred individuals into the wild to restore or augment wild populations of songbirds A before-and-after study in Mauritius describes the establishment of a population of Mauritius fody Foudia rubra following the release of captive-bred individuals. Four studies of three release programmes on Hawaii found high survival of all three species released (Hawaiian crows Corvus hawaiiensis and two thrushes: omao Myadestes obscurus and puaiohi M. palmeri), with the two thrushes successfully breeding. The authors in one note that many of the released puaiohi dispersed from the release site, meaning that repopulating specific areas may require multiple releases. A replicated, controlled study from the USA found that San Clemente loggerhead shrike Lanius ludovicianus mearnsi pairs with captive-bred females had lower reproductive success than pairs where both parents were wild-bred. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F630https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F630Sun, 14 Oct 2012 23:05:39 +0100Collected Evidence: Collected Evidence: Use holding pens at release sites Three replicated and one small study from three release programmes in Saudi Arabia, the USA and Canada found that released birds had higher survival or were more likely to pair up if kept at release sites in holding pens before release. A replicated study in the USA found lower survival for thick-billed parrots Rhynchopsitta pachyrhyncha released in holding pens, compared to birds released without preparation. A review of northern bald ibis Geronticus eremita conservation found that holding pens successfully prevented most birds from migrating (which resulted in 100% mortality), although some 200 birds ‘escaped’ over 25 years. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F632https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F632Sun, 14 Oct 2012 23:22:45 +0100Collected Evidence: Collected Evidence: Use ‘warmer’ (red/yellow) lighting rather than other lighting colours Five studies evaluated the effects on butterflies and moths of using ‘warmer’ (red/yellow) lighting rather than other lighting colours. Two studies were in the Netherlands and one study was in each of Germany, Slovenia and the UK. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (5 STUDIES) Behaviour change (5 studies): Four replicated, controlled studies (including one randomized, paired study and two paired studies) in Germany, the Netherlands, Slovenia and the UK found that fewer individual moths, and moth species, were attracted to yellow, green, white or red lights (which in one case also emitted at a lower intensity) than to UV, actinic, blue or conventional metal halide lights. One replicated, randomized, paired, controlled study in the Netherlands found that four moth species spent more time feeding under red lights than under white or green lights, but less time feeding than when in complete darkness. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3906https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3906Tue, 09 Aug 2022 15:23:37 +0100Collected Evidence: Collected Evidence: Increase grazing intensity or cutting frequency on grassland Five studies evaluated the effects on butterflies and moths of increasing grazing intensity or cutting frequency on grassland. Two studies were in Germany, and one study was in each of the Czech Republic, the USA and Israel. COMMUNITY RESPONSE (1 STUDY) Richness/diversity (1 study): One replicated, site comparison study in Germany found that at intensively grazed sites species richness of adult butterflies and burnet moths was lower than at sites with low or no grazing, but caterpillar richness was lower in intensively grazed and low grazing sites than in sites with no grazing. POPULATION RESPONSE (5 STUDIES) Abundance (5 studies): Four studies (including one replicated, randomized, paired, controlled study, one replicated, site comparison study, and two site comparison studies) in Germany, the USA and Israel found that grasslands managed with more intensive grazing or with grazing in addition to rotational burning had a lower abundance of all adult butterflies, adult burnet moths, adult regal fritillaries and spring webworm caterpillar nests than ungrazed grasslands, lightly or moderately grazed grasslands or rotationally burned grasslands with occasional light grazing. However, one of these studies found that, while intensively grazed sites had lower butterfly and burnet moth caterpillar abundance than ungrazed sites, there was no difference in caterpillar abundance between ungrazed and lightly grazed sites. One before-and-after study in the Czech Republic reported that after increasing the cutting frequency on traditional meadows (under agri-environment scheme prescriptions) the abundance of Danube clouded yellow decreased. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3962https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3962Sun, 14 Aug 2022 10:37:50 +0100Collected Evidence: Collected Evidence: Maintain or restore traditional water meadows and bogs Five studies evaluated the effect on butterflies and moths of maintaining or restoring traditional water meadows and bogs. Two studies were in the UK and one was in each of Germany, Belgium and Poland. COMMUNITY RESPONSE (1 STUDY) Richness/diversity (1 study): One replicated, site comparison study in Germany found that the species richness of butterflies was similar in wet meadows managed by mowing once/year in autumn, or by light grazing with cattle or horses. POPULATION RESPONSE (4 STUDIES) Abundance (4 studies): One of two replicated, before-and-after studies in Belgium and Poland found that after cattle grazing on wet grassland began, the number of bog fritillaries which emerged on grazed areas was lower than before grazing started. The other study reported that after trees and shrubs were removed from wet meadows, the number of marsh fritillary caterpillar webs increased the following year. One replicated, site comparison study in Germany found that the abundance of butterflies was similar in wet meadows managed by mowing once/year in autumn, or by light grazing with cattle or horses. One site comparison study in the UK found that wet grassland grazed at an intermediate intensity by cattle had a higher abundance of marsh fritillary caterpillar webs, but a similar abundance of adults, to grassland grazed at high or low intensity. BEHAVIOUR (2 STUDIES) Use (2 studies): One replicated, before-and-after study in Belgium found that after cattle grazing on wet grassland began, the use of the grazed areas by bog fritillaries was lower than before grazing started. One replicated, site comparison study in the UK found that a similar proportion of fen meadows were occupied by marsh fritillary caterpillars whether they were managed by grazing (with cattle, sheep or horses), burning or were unmanaged. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3971https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3971Sun, 14 Aug 2022 10:39:58 +0100Collected Evidence: Collected Evidence: Reduce field size (or maintain small fields) Five studies evaluated the effects of reducing field size on butterflies and moths. Two studies were in Switzerland, and one was in each of Germany, Sweden and the Czech Republic and Poland. COMMUNITY RESPONSE (5 STUDIES) Richness/diversity (5 studies): Two of four replicated, site comparison studies in Sweden, the Czech Republic and Poland and Switzerland found that arable farms (in more diverse landscapes) and landscapes with smaller fields had a higher species richness of butterflies and burnet moths than areas with larger fields. The other two studies found that mixed farms and landscapes with smaller fields had a similar species richness of butterflies to areas with larger fields. One before-and-after study in Germany found that after reducing field size by increasing the length of field edges on a farm, along with increasing the area of meadows and field margins, the species richness of butterflies and burnet moths increased. POPULATION RESPONSE (4 STUDIES) Abundance (4 studies): Four replicated, site comparison studies in Sweden, the Czech Republic and Poland and Switzerland found that arable and mixed farms and landscapes with smaller fields had a higher abundance of butterflies and burnet moths than areas with larger fields. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3974https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3974Thu, 18 Aug 2022 09:04:31 +0100