Collected Evidence: Collected Evidence: Reduce tillage Four replicated and controlled studies from North America and Canada and the UK and two literature reviews found that some or all bird groups had higher species richness or diversity on reduced-tillage fields, compared to conventional field in some areas. Two replicated and controlled studies from Canada and the UK and a review found that some measures of diversity were lower, or no different, on reduced-tillage fields, compared to conventional fields. Five replicated and controlled studies from the USA and Europe, a small study and two reviews all found that some bird species are found at higher densities on fields with reduced tillage than conventional fields. Five replicated and controlled studies from the USA, Canada and Europe, and a review found that some or all species were found at similar or lower densities on reduced-tillage fields compared to conventional fields, with one finding that preferences decreased over time (possibly due to extreme weather) and another finding that preferences were only found in spring. Two controlled studies (one replicated) and a review found evidence for higher productivity, nesting success or earlier laying on reduced tillage fields, compared to conventional fields. One controlled study found no evidence for greater success or larger chicks on reduced-tillage fields.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F211https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F211Mon, 16 Jul 2012 17:11:41 +0100Collected Evidence: Collected Evidence: Mark power lines to reduce incidental bird mortality A total of eight studies and two literature reviews from across the world found that marking power lines led to significant reductions in collision rates or dangerous flight behaviour (i.e. approaching close to power lines) in cranes Grus spp., mute swans Cygnus olor and other bird species. All markers except thin, black plastic strips or neoprene crosses were effective, with no differences in effectiveness between Bird Flight Diverters (BFDs: brightly coloured plastic spirals) and static fibreglass plates and only a small possible difference between BFDs and ‘flappers’ (moving markers).  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F265https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F265Thu, 19 Jul 2012 14:03:03 +0100Collected Evidence: Collected Evidence: Use signs and access restrictions to reduce disturbance at nest sites Six studies (two replicated and controlled, two before-and-after and two small studies) from across the world found increased numbers of breeders, higher reproductive success or lower levels of disturbance in waders and terns following the start of access restrictions or the erection of signs near nesting areas. One Canadian study involved the use of multiple interventions. A before-and-after study from the USA found that a colony of black-crowned night herons Nycticorax nycticorax was successfully relocated to an area with no public access. One small study from Europe and one replicated and controlled study from Antarctica found no effect of access restrictions on the reproductive success of eagles or penguins, respectively.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F309https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F309Wed, 25 Jul 2012 16:56:43 +0100Collected Evidence: Collected Evidence: Employ grazing in artificial grasslands/pastures Of ten studies captured, one replicated, controlled study from the USA found lower species richness in grazed areas than ungrazed. Another replicated, controlled study from the USA found no consistent differences in community composition between grazed and ungrazed areas. A small study from Canada found an increase in duck populations following the start of grazing amongst other interventions. Five studies from the UK and USA, four replicated, found higher use of, or higher nesting densities in, grazed areas compared to ungrazed. Seven studies from the UK, Canada and the USA, five replicated, found no differences in use or nesting densities, or lower abundances of birds on grazed, compared with ungrazed areas. One found that several species appeared to be excluded by grazing. Three studies from the UK, USA and Canada, two replicated, found that nesting success or productivity was similar, or lower, on grazed sites compared with ungrazed.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F349https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F349Sun, 29 Jul 2012 14:59:09 +0100Collected Evidence: Collected Evidence: Control avian predators on islands Out of 10 studies, six before-and-after studies from North America, Australia and Europe found that controlling avian predators led to increased population sizes, reduced mortality or increased reproductive success in seabirds on islands. The North American studies had several interventions, so increases could not be linked directly to predator control, and one found that increases were only at one of two sites studied. Two controlled studies in Europe found little evidence that crow control led to increased reproductive success in gamebirds or raptors on islands. A North American study found that, despite higher reproductive success, very few birds returned to the study site after predator removal. A study from North America found that an Atlantic puffin Fratercula arctica translocation programme, combined with the culling of predatory gulls, appeared to be successful. A study from the UK found that the number of common terns Sterna hirundo and black-headed gulls Larus ridibundus declined on gravel islands despite the attempted control of large gulls.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F372https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F372Tue, 07 Aug 2012 14:43:03 +0100Collected Evidence: Collected Evidence: Control predators not on islands for songbirds A before-and-after study from New Zealand found that a reintroduced population of New Zealand robins Petroica australis declined without predator control and increased with rat poisoning. Two UK studies, one non-experimental, found increased populations of some species following control of bird and mammal predators. One replicated, controlled study from New Zealand found lower New Zealand robin survival in areas where rodent bait was broadcast, but no difference with controls when dispensers were used. Six studies from New Zealand, Australia, UK found increased nest success or survival (in one case with artificial nests) following bird and mammal predator control. One randomised, replicated and controlled study from the USA found no difference in nest survival in a site with mammalian predator removal.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F392https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F392Thu, 09 Aug 2012 13:08:55 +0100Collected Evidence: Collected Evidence: Create alternative bat roosts within developments Eleven studies evaluated the effects of creating alternative bat roosts within developments on bat populations. Nine studies were in Europe and two were in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (11 STUDIES)     Use: (11 studies): Two replicated studies in the USA and UK found that bats did not use any of the alternative roosts provided in bat houses or a purpose-built bat wall after exclusion from buildings. Three studies (two replicated) in the USA and UK and one review in the UK found that bat boxes or bat lofts/barns were used by bats at 13–74% of development sites, and bat lofts/barns were used by maternity colonies at one of 19 development sites. Three of five before-and-after studies in Portugal, Ireland, Spain and the UK found that bat colonies used purpose-built roosts in higher or similar numbers after the original roosts were destroyed. The other two studies found that bats used purpose-built roosts in lower numbers than the original roost. One review in the UK found that new bat boxes/lofts built to replace destroyed roosts were four times less likely to be used by returning bats than roosts retained during development. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F949https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F949Fri, 20 Dec 2013 09:21:55 +0000Collected Evidence: Collected Evidence: Thin trees within forest and woodland Eleven studies evaluated the effects of thinning trees within forest and woodland on bat populations. Six studies were in the USA, four were in Australia and one was in Canada. COMMUNITY RESPONSE (2 STUDIES) Richness/diversity (2 studies): One replicated, site comparison study in Australia recorded the same bat species in thinned and unthinned forest, except for the chocolate wattled bat, which was not recorded in forests with unthinned regrowth. One replicated, site comparison study in Australia found that forest thinned up to 20 years previously had higher bat diversity than unthinned forest, but sites thinned more than 20 years previously did not differ. POPULATION RESPONSE (11 STUDIES) Abundance (11 studies): Five of six replicated, site comparison studies (including two paired sites studies and one controlled study) in the USA and Australia found higher overall bat activity (relative abundance) in thinned or thinned and burned forest than unthinned forest. The other study found similar overall bat activity in thinned and unthinned stands. One replicated, randomized, site comparison study in the USA found higher overall bat activity for three of four types of thinning and burning treatments. One replicated, site comparison study in Australia found that forest thinned up to eight years previously or more than 20 years previously had higher bat activity than unthinned forest, but sites thinned 8–20 years previously did not differ. Three replicated, controlled studies (including one site comparison and one before-and-after study) in Canada and Australia found that thinning increased the activity of some bat species but not others. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F991https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F991Fri, 20 Dec 2013 15:31:59 +0000Collected Evidence: Collected Evidence: Install and maintain cave gates to restrict public access Eleven studies evaluated the effects of installing cave gates on bat populations. Six studies were in the USA and five studies were in Europe. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (7 STUDIES) Abundance (7 studies): Three of four before-and-after studies (including one replicated study and one controlled study) in the Netherlands, the USA, Spain and Turkey found more or similar numbers of bats in caves and a bunker after gates were installed to restrict public access. The other study found fewer bats in caves after gates were installed. Two before-and-after studies in the USA and Spain found more bats within two caves after the size of the gated entrances were increased. One replicated, before-and-after study in the USA found that installing cave gates resulted in population increases or decreased rates of decline for 13 of 20 colonies of Indiana bat. One replicated, site comparison study in Spain found no difference in the population growth rates of bats roosting in caves with and without cave gates. Condition (1 study): One site comparison study in the USA found that bats hibernating in a cave with a wall and gate over the entrance lost more body mass than bats in a nearby unmodified cave. BEHAVIOUR (5 STUDIES)   Use (1 study): One replicated, site comparison study in Spain found no difference in the occupancy rates of bats roosting in caves with and without cave gates. Behaviour change (4 studies): One replicated, controlled, before-and-after and site comparison study in the USA found that bats at cave entrances circled more and entered caves less after gates were installed. One replicated study in the USA found that bats flew through gates with a funnel design more frequently than gates with a round bar or angle iron design. One randomized, controlled, before-and-after study in the UK found that fewer bats flew through cave gates when the spacing between horizontal bars was reduced. One before-and-after study in the USA found that significantly fewer bats emerged from a cave with a gate installed compared with a cave with a fence. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F999https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F999Fri, 20 Dec 2013 17:07:52 +0000Collected Evidence: Collected Evidence: Crop production: Use organic fertilizer instead of inorganicCrop yield (11 studies) Food crops (10 studies): Four replicated studies (three controlled, two randomized; one site comparison) from Italy and Spain found higher yields in plots with organic fertilizer, compared to inorganic fertilizer, in some comparisons. Three replicated, randomized, controlled studies from Spain and the USA found lower yields in plots with organic fertilizer, compared to inorganic fertilizer, in some or all comparisons. Three replicated, randomized, controlled studies from Greece and Spain found similar yields in plots with organic or inorganic fertilizer. Forage crops (1 study): One replicated, randomized, controlled study from Spain found higher alfalfa yields in plots with organic fertilizer, compared to inorganic, in one of two comparisons. Crop quality (0 studies)  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1350https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1350Mon, 20 Mar 2017 16:57:26 +0000Collected Evidence: Collected Evidence: Soil: Add manure to the soilOrganic matter (8 studies): Five replicated, controlled studies (two randomized) from Italy, Tunisia, Turkey, and the USA found more organic matter in soils with added manure, compared to soils without it. Three replicated, randomized, controlled studies from Italy, Spain, and Greece found similar amounts of organic matter in plots with or without added manure. Nutrients (5 studies) Nitrogen (5 studies): Three replicated, controlled, studies (one randomized) from Italy and Tunisia found more nitrogen in soils with added manure, compared to soils without it, in some comparisons. Two replicated, randomized, controlled studies from Greece and Italy found similar amounts of nitrogen in soils with or without added manure. Phosphorus (3 studies): One replicated, randomized, controlled study from Greece found more phosphorus in soils with added manure, compared to soils without it. One replicated, randomized, controlled study from Italy found similar amounts of phosphorus in soils with or without added manure. One replicated, controlled study from Italy found inconsistent differences in phosphorus between soils with or without added manure. Potassium (2 studies): Two replicated, randomized, controlled studies from Italy and Greece found more potassium in soils with added manure, compared to soils without it. pH (3 studies): One replicated, randomized, controlled study from Tunisia found lower pH levels in soils with added manure, compared to soils without it. One replicated, controlled study from Italy found higher pH levels in soils with added manure. One replicated, randomized, controlled study from Italy found similar pH level in soils with or without added manure. Soil organisms (3 studies) Microbial biomass (2 studies): Two replicated, randomized, controlled studies from Italy and Spain found similar amounts of microbial biomass in soils with or without added manure. Nematodes (1 study): One replicated, randomized, controlled study from Greece found similar numbers of nematodes in soils with or without added manure. Soil erosion and aggregation (4 studies): One replicated, randomized, controlled study from Spain found less erosion in plots with added manure, compared to plots without added manure. Three replicated, randomized, controlled studies from Spain and Turkey found higher soil stability in plots with added manure, compared to plots without added manure, in some or all comparisons. One replicated, controlled study from the USA found similar soil stability in plots with or without added manure. Greenhouse gases (2 studies): One replicated, controlled study from the USA found higher carbon dioxide emissions in plots with added manure, compared to plots without added manure. One replicated, randomized, controlled study from Spain found higher nitrous oxide emissions in plots with added manure, compared to plots without added manure. Implementation options (1 study): One study from Tunisia found no differences in organic matter or pH between soils with different amounts of added manure, but found less nitrate in soils with less added fertilizer.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1363https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1363Tue, 09 May 2017 10:32:58 +0100Collected Evidence: Collected Evidence: Water: Use organic fertilizer instead of inorganicWater use (0 studies) Water availability (5 studies): Two replicated, randomized, controlled studies from Spain found similar amounts of water-filled pore space in plots with organic or inorganic fertilizer. Two replicated studies (one randomized and controlled, one site comparison) from France and Turkey found more water in plots with organic fertilizer, compared to inorganic fertilizer. One replicated, randomized, controlled study from Spain found less water in plots with organic fertilizer, compared to inorganic fertilizer, in one of two comparisons. Pathogens and pesticides (0 studies) Nutrients (6 studies): Two replicated, randomized, controlled studies from Italy and Spain found that less nitrate was lost from plots with organic fertilizer, compared to inorganic fertilizer, in some comparisons. One of these studies also found that more dissolved organic matter was lost, in one of two comparisons. One replicated, randomized, controlled study from Spain found more nitrate in runoff from plots with organic fertilizer, compared to inorganic fertilizer. Three replicated, controlled studies (two randomized) from Portugal and Spain found that similar amounts of nitrogen were lost from plots with organic or inorganic fertilizer. Sediments (0 studies) Implementation options (1 study): One study from Spain found that less nitrate, but more organic matter, was leached from plots that were fertilized with manure, compared to slurry.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1381https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1381Mon, 15 May 2017 15:31:47 +0100Collected Evidence: Collected Evidence: Cut/remove/thin forest plantations and rewet peat Eleven studies evaluated the effects of cutting/removing trees and rewetting peat (in combination): six in fens, two in bogs, and three in both fens and bogs. In four of the studies, the peatlands naturally contained some trees. Three studies were based on one experimental set-up, and two studies were based on another. Plant community composition (5 studies): Of three replicated studies in fens, two in Finland found that removing trees/rewetting had no effect on the overall plant community composition whilst one in Sweden reported only a small effect. Two site comparison studies in bogs and fens in Finland found that removing trees/rewetting changed the overall plant community composition. It became less like sites that remained drained and forested. Characteristic plants (2 studies): Two before-and-after studies (one site comparison, one controlled) in bogs and fens in Finland and Sweden reported that removing trees/rewetting increased the abundance of wetland-characteristic plants. Moss cover (6 studies): Of five studies that examined the effect of removing trees/rewetting on Sphagnum moss, two replicated, paired studies in bogs and fens in Sweden and Finland found that the intervention increased Sphagnum cover. One replicated, before-and-after, site comparison study in forested fens in Finland found no effect. Two before-and-after studies in a bog in Finland and a fen in Sweden found mixed effects depending on site or species. Additionally, three studies (two replicated and paired) in peatlands in the UK and Finland found that removing trees/rewetting reduced cover of non-Sphagnum or forest-characteristic mosses. However, one replicated, before-and-after, site comparison study in forested fens in Finland found no effect of thinning trees/rewetting on forest mosses. Herb cover (7 studies): Seven studies (including two replicated, paired, controlled) in bogs and fens in the UK, Finland and Sweden reported that removing trees/rewetting increased cover of at least one group of herbs, including cottongrasses and sedges. However, one of these studies reported loss of cottongrass from a fen where it was rare before intervention, along with reduced purple moor grass cover. Vegetation structure (4 studies): One replicated site comparison study in a bog in the UK found that removing trees/rewetting increased ground vegetation height. One replicated, paired, controlled study in a fen in Sweden reported that removing trees/rewetting had no effect on canopy height after eight years. Two replicated, paired, site comparison studies in bogs and fens in Finland found that thinning trees/rewetting reduced the number of tall trees present for 1–3 years (although not to the level of natural peatlands). Overall plant richness/diversity (4 studies): Two replicated, paired, controlled studies in rich fens in Sweden reported that removing trees/rewetting increased plant species richness. However, two replicated studies in fens in Finland found that removing trees/rewetting had no effect on total plant species richness or diversity. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1732https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1732Mon, 27 Nov 2017 21:16:46 +0000Collected Evidence: Collected Evidence: Directly plant peatland trees/shrubs Eleven studies evaluated the effects, on peatland vegetation, of planting trees/shrubs to restore or create forested/shrubby peatland. Seven studies were in tropical peat swamps, three in bogs and one in a fen. Survival (10 studies): Eight studies (seven replicated) in peat swamp forests in Thailand, Malaysia and Indonesia and bogs in Canada reported that the majority of planted trees/shrubs survived over periods between 10 weeks and 13 years. Species with <50% survival included Dacryodes, poplar and katok. One replicated study in a fen in the USA reported that most planted willow cuttings died within two years. One study in a peat swamp forest in Indonesia reported <5% survival of planted trees after five months, following unusually deep flooding. Growth (5 studies): Four studies (including two replicated, before-and-after) in peat swamp forests in Thailand, Indonesia and Malaysia reported that planted trees grew. One replicated before-and-after study in bogs in Canada reported that planted shrubs grew. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1820https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1820Tue, 28 Nov 2017 08:45:21 +0000Collected Evidence: Collected Evidence: Translocate problem mammals away from residential areas (e.g. habituated bears) to reduce human-wildlife conflict Eleven studies evaluated the effects of translocating problem mammals (such as bears) away from residential areas to reduce human-wildlife conflict. Six studies were in the USA, two were in Canada, one was Russia, one was in India and one was in Romania. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (6 STUDIES) Survival (6 studies): A controlled study in the USA found that grizzly bears translocated away from conflict situations had lower survival rates than did non-translocated bears. A replicated study study in the USA found that fewer than half of black bears translocated from conflict situations survived after one year. Two of three studies (two controlled), in the USA, found that after translocation away from urban sites, white-tailed deer survival was lower than that of non-translocated deer. The third study found that short-term survival was lower but long-term survival was higher than that of non-translocated deer. A study in Russia found that most Amur tigers translocated after attacking dogs or people did not survive for a year after release. BEHAVIOUR (0 STUDIES) OTHER (6 STUDIES) Human-wildlife conflict (6 studies): Five studies (including one controlled and two replicated studies), in the USA and Canada, of brown/grizzly or black bears translocated away from residential areas or human-related facilities, found that at least some returned to their original capture location and/or continued to cause nuisance. In two of the studies, most returned to their capture area and one black bear returned six times following translocation. A before-and-after study in India found that leopards translocated away from human-dominated areas, attacked more humans and livestock than before-translocation. A controlled study in Romania found that translocated brown bears occurred less frequently inside high potential conflict areas than outside, the opposite to bears that had not been translocated. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2336https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2336Thu, 21 May 2020 14:09:47 +0100Collected Evidence: Collected Evidence: Install electric fencing to reduce predation of livestock by mammals to reduce human-wildlife conflict Eleven studies evaluated the effects of installing electric fencing to reduce predation of livestock by mammals to reduce human-wildlife conflict. Six studies were in the USA (and a further one was presumed to be in the USA) and one each was in Canada, South Africa, Brazil and Spain. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (11 STUDIES) Human-wildlife conflict (11 studies): Six out of 10 randomized and/or controlled or before-and-after studies (including eight replicated studies), in the USA (and a further one presumed to be in the USA), Canada, Brazil and Spain, found that electric fences reduced or prevented entry to livestock enclosures or predation of livestock by carnivores. Two studies found that some designs of electric fencing prevented coyotes from entering enclosures and killing or wounding lambs. The other two studies found electric fencing did not reduce livestock predation or prevent fence crossings by carnivores. A before-and-after study in South Africa found that electrifying a fence reduced digging of burrows under the fence that black-backed jackals could pass through. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2417https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2417Mon, 01 Jun 2020 10:09:18 +0100Collected Evidence: Collected Evidence: Translocate predators away from livestock to reduce human-wildlife conflict Eleven studies evaluated the effects on mammals of translocating predators away from livestock to reduce human-wildlife conflict. Four studies were in the USA two were in Botswana, one each was in Canada, Zimbabwe and Namibia, one was in Venezuela and Brazil and one covered multiple locations in North and Central America and Africa. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (8 STUDIES) Reproductive success (2 studies): Two studies, in Zimbabwe and Namibia, found that predators translocated away from livestock bred in the wild after release. Survival (8 studies): Four of eight studies (including three replicated studies and a systematic review), in the USA, Canada, Zimbabwe, South America, Botswana and Namibia, found that translocating predators reduced their survival or that most did not survive more than 6–12 months after release. Three studies found that translocated predators had similar survival to that of established animals or persisted in the wild and one study could not determine the effect of translocation on survival. BEHAVIOUR (0 STUDIES) OTHER (6 STUDIES) Human-wildlife conflict (6 studies): Four of six studies (including a review and a systematic review), in the USA, South America and in North and Central America and Africa, found that some translocated predators continued to predate livestock or returned to their capture sites. One study found that translocated predators were not subsequently involved in livestock predation and one study could not determine the effect of translocation on livestock predation. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2436https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2436Tue, 02 Jun 2020 09:18:02 +0100Collected Evidence: Collected Evidence: Install electric fencing to protect crops from mammals to reduce human-wildlife conflict Eleven studies evaluated the effects of installing electric fencing to protect crops from mammals to reduce human-wildlife conflict. Three studies were in Japan, three were in the USA, two were in the UK and one each was in Namibia, India and Guinea-Bissau. KEY COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (11 studies) Human-wildlife conflict (11 studies): Nine of 11 studies (including three before-and-after studies and three controlled studies), in the USA, the UK, Japan, Namibia, India and Guinea-Bissau, found that electric fences deterred crossings by mammals, ranging in size from European rabbits to elephants. Two studies had mixed results, with some fence designs deterring elephants and black bears. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2439https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2439Tue, 02 Jun 2020 09:46:58 +0100Collected Evidence: Collected Evidence: Use a different bait type Eleven studies examined the effects of using different bait on marine fish populations. Two studies were global systematic reviews. Three studies were in the North Atlantic Ocean (USA, Iceland).Two studies were in the South Pacific Ocean (New Zealand). One study was in each of the Norwegian/Barents Seas (Norway), the Barents Sea (Norway), the Denmark Strait (Greenland) and the Mediterranean Sea. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Survival (2 studies): One replicated study in the South Pacific Ocean and one global systematic review found that using different bait species did not reduce hooking injuries (associated with higher post-release mortality) of undersized snapper or sharks and rays, and did not increase survival of sharks and rays on gear retrieval. BEHAVIOUR (0 STUDIES) OTHER (10 STUDIES) Reduction of unwanted catch (10 studies): Six of eight replicated studies (three controlled and one randomized) in the Norwegian/Barents Seas, Barents Sea, Denmark Strait, North Atlantic Ocean, Mediterranean Sea and the South Pacific Ocean, found that using a different bait type (including size, species and manufacture method) reduced the unwanted catches of undersized haddock (although in one case in only two of six comparisons), Atlantic cod and other unwanted or non-target fish catch, but unwanted catches of torsk and ling were similar, compared to standard or other bait types. Two other studies found no reduction in unwanted catches of pelagic stingray and overall unwanted fish with different bait types. Two systematic global reviews found that using different bait types did not affect the number of unwanted sharks and rays caught. Improved size-selectivity of fishing gear (1 study): One replicated study in the Denmark Strait found that using a different bait species increased the size-selectivity of commercially targeted Greenland halibut. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2700https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2700Thu, 10 Dec 2020 14:26:24 +0000Collected Evidence: Collected Evidence: Rescue and release stranded or trapped marine and freshwater mammals Eleven studies evaluated the effects of rescuing and releasing stranded or trapped marine and freshwater mammals. Five studies were in the North Atlantic Ocean (USA), two studies were in the Indian Ocean (Tasmania, South Africa), and one study was in each of the South Atlantic Ocean (Brazil), the Cachoeira River estuary (Brazil), the North Pacific Ocean (USA) and the Shannon Estuary (Ireland). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (11 STUDIES) Reproductive success (2 studies): One review in the North Pacific Ocean found that after rescuing and releasing stranded or trapped Hawaiian monk seals, along with at least seven other interventions to enhance survival, more than a quarter of the seals reproduced. One study in the Shannon Estuary found that a stranded common bottlenose dolphin that was rescued and released was observed with a calf a year later. Survival (11 studies): Seven studies (including one review) in the North Atlantic Ocean, Indian Ocean and the Shannon Estuary found that 17–100% of rescued and released Atlantic white-sided dolphins, short-beaked common dolphins, common bottlenose dolphins, long-finned pilot whales, short-finned pilot whales, and Cape fur seals survived during post-release monitoring periods, which ranged in length from three weeks to three years. Three studies in the South Atlantic Ocean, the Cachoeira estuary and the Indian Ocean found that a trapped rough-toothed dolphin, two stranded tucuxi dolphins and seven stranded sperm whales were successfully rescued and released, although long-term survival was not reported. One review in the North Pacific Ocean found that rescuing and releasing stranded or trapped Hawaiian monk seals, along with at least seven other interventions to enhance survival, resulted in more than a quarter of the seals surviving. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2924https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2924Mon, 08 Feb 2021 16:51:49 +0000Collected Evidence: Collected Evidence: Transplant or seed organisms onto subtidal artificial structures Eleven studies examined the effects of transplanting or seeding species onto subtidal artificial structures on the biodiversity of those structures. Eight studies were on open coastlines in Japan, Italy and Croatia, and one of each was in an inland bay in eastern USA, an estuary in southeast Australia, and on an island coastline in the Singapore Strait. COMMUNITY RESPONSE (2 STUDIES) Overall community composition (1 study): One replicated, paired sites, controlled study in the USA found that transplanting oysters onto subtidal artificial structures altered the combined invertebrate and fish community composition on and around structure surfaces. Overall richness/diversity (1 study): One replicated, paired sites, controlled study in the USA found that transplanting oysters onto subtidal artificial structures increased the combined invertebrate and fish species richness and diversity on and around structure surfaces. Invertebrate richness/diversity (1 study): One randomized, before-and-after study in Singapore reported that transplanting corals onto a subtidal artificial structure increased the coral species richness on structure surfaces. POPULATION RESPONSE (11 STUDIES) Overall abundance (1 study): One replicated, paired sites, controlled study in the USA found that transplanting oysters onto subtidal artificial structures did not increase the combined invertebrate and fish abundance on and around structure surfaces, but that the effects varied for different species. Algal abundance (3 studies): Two replicated, randomized, controlled studies in Italy and Croatia found that the cover of canopy algae transplanted onto subtidal artificial structures increased and/or was higher when transplanted under cages but decreased and/or was lower when left uncaged. One study in Japan reported that the abundance of kelp recruits on a subtidal artificial structure varied depending on the distance from transplanted kelp individuals and the surface orientation. Invertebrate abundance (2 studies): One replicated, randomized, controlled and site comparison study in Australia found that transplanting sea urchins onto a subtidal artificial structure reduced the cover of non-native sea mat on kelps growing on the structure. One randomized, before-and-after study in Singapore reported that transplanting corals increased the coral cover on structure surfaces. Algal reproductive success (1 study): One study in Japan reported that kelp transplanted onto a subtidal artificial structure appeared to reproduce. Invertebrate reproductive success (1 study): One replicated, paired sites, controlled study in the USA reported that oysters transplanted onto subtidal artificial structures appeared to reproduce. Algal survival (5 studies): Three of five replicated studies (including two randomized, controlled studies) in Italy found that the survival of canopy algae transplanted onto subtidal artificial structures varied depending on the wave-exposure and surrounding habitat or the presence and/or mesh size of cages around transplants, while in one the surface orientation had no effect. Two studies reported that no canopy algae transplants survived, and in one this was regardless of the presence of cages. Invertebrate survival (3 studies): One randomized, before-and-after study in Singapore found that the survival of corals transplanted onto a subtidal artificial structure varied depending on the species. One replicated, paired sites, controlled study in the USA found that cleaning activities did not affect survival of transplanted oysters. One replicated, randomized, controlled and site comparison study in Australia simply reported that transplanted sea urchins survived. Algal condition (3 studies): Two replicated studies (including one randomized, controlled study) in Italy found that the growth of canopy algae transplanted onto subtidal artificial structures varied depending on the wave-exposure and surface orientation or the presence of cages around transplants, while in one the mesh size of cages had no effect. One study in Japan simply reported that transplanted kelp grew. Invertebrate condition (2 studies): One randomized, before-and-after study in Singapore reported that the growth of corals transplanted onto a subtidal artificial structure varied depending on the species. One replicated, paired sites, controlled study in the USA reported that cleaning activities did not affect the growth of transplanted oysters. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3471https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3471Fri, 17 Sep 2021 12:57:05 +0100Collected Evidence: Collected Evidence: Use circle hooks instead of J-hooks Eleven studies evaluated the effects of using circle hooks instead of J-hooks on reptile populations. Five studies were in the Atlantic, three were in the Pacific and one study was in each of the Mediterranean, the Atlantic and North Pacific and the western North Atlantic, Azores, Gulf of Mexico and Ecuador. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (3 STUDIES) Survival (3 studies): Two studies (including one replicated, controlled, paired study) off the coast of Hawaii and in the north-east Atlantic Ocean found that survival of loggerhead and leatherback turtles and leatherback and hard-shell sea turtles caught by circle hooks or J-hooks was similar. One review of studies in five pelagic longline fisheries found that fewer sea turtles died when circle hooks were used compared to J-hooks in four of five fisheries. Condition (3 studies): Two replicated, controlled studies in the Mediterranean Sea and south-western Atlantic Ocean found that fewer immature loggerhead turtles and loggerhead turtles swallowed circle hooks compared to J-hooks. One before-and-after study off the coast of Hawaii found that a lower percentage of loggerhead and leatherback turtles were deeply hooked by circle hooks compared to J-hooks. BEHAVIOUR (0 STUDIES) OTHER (11 STUDIES) Unwanted catch (11 studies): Seven of 10 studies (including six replicated, controlled studies) in the Pacific, Atlantic, Atlantic and North Pacific and Mediterranean and one review of studies in five pelagic longline fisheries found that circle hooks or circle hooks and tuna hooks caught fewer sea turtles than J-hooks, or that non-offset G-style circle hooks caught fewer leatherback and hard-shell sea turtles that offset J-Hooks. One of these studies also found that circle hooks caught slightly larger loggerhead turtles than J-hooks, and one also found that offset Gt-style circle hooks caught a similar number of leatherback and hard-shell sea turtles compared to offset J-hooks. One study found that circle hooks caught a similar number of leatherback, green and olive ridley turtles compared to J-hooks. One study found that fish-baited circle hooks caught fewer loggerhead and leatherback turtles than squid-baited J-hooks. The review found mixed effects of using circle hooks compared to J-hooks on unwanted catch of sea turtles depending on the fishery. The other study found mixed effects of using circle hooks or J-hooks in combination with squid or fish bait on the number of loggerhead and leatherback turtles that were caught. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3559https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3559Wed, 08 Dec 2021 14:21:43 +0000Collected Evidence: Collected Evidence: Create artificial refuges, hibernacula and aestivation sites Eleven studies evaluated the effects of creating artificial refuges, hibernacula and aestivation sites on reptile populations. Three studies were in each of the UK and Australia, two were in New Zealand and one was in each of the USA, Spain and Italy. COMMUNITY RESPONSE (1 STUDY) Richness/diversity (1 study): One controlled, before-and-after study in Spain found that areas with refuge logs had higher reptile species richness than areas without refuges. POPULATION RESPONSE (3 STUDIES) Abundance (1 study): One controlled, before-and-after study in Spain found that areas with refuge logs had a higher abundance of reptiles than areas without refuges. Reproductive success (1 study): One study in the UK found that after translocating adders to an artificial hibernaculum, there was evidence of successful reproduction. Survival (1 study): One randomized, controlled, before-and-after study in New Zealand found that in areas with artificial refuges, survival of McCann’s skinks was similar to areas without refuges. BEHAVIOUR (9 STUDIES) Use (9 studies): Nine studies (including one replicated, controlled study and one randomized, controlled study) in the USA, the UK, Australia, New Zealand and Italy found that artificial refuges were used by reptiles, common lizards, adders, common geckos, species of skinks, and by an ocellated lizard to lay a clutch of eggs. Four of the studies also found that some reptiles showed a preference for refuges with certain designs or construction materials. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3720https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3720Mon, 13 Dec 2021 16:36:45 +0000Collected Evidence: Collected Evidence: Reduce fertilizer, pesticide or herbicide use generally Eleven studies evaluated the effects on butterflies and moths of reducing fertilizer, pesticide or herbicide use generally. Three studies were in the UK, two were in each of the USA and Germany, one was in each of Spain, Mexico and Switzerland, and one was a systematic review across Europe. COMMUNITY RESPONSE (10 STUDIES) Richness/diversity (10 studies): Eight studies (including one replicated study, two controlled studies, one randomized study, five site comparison studies, and one systematic review) in the USA, Europe, the UK, Spain, Mexico and Switzerland found that orchards, crop edges, farms, vineyards, replanted Douglas fir stands, coffee plantations and agricultural landscapes managed with less frequent, reduced or no pesticide, herbicide, fertilizer or unspecified chemical input (sometimes along with other agri-environment scheme options or less intensive management) had a greater species richness of adult butterflies and moths, or caterpillars (in one case along with other leaf-eating arthropods), than areas with more frequent or conventional chemical applications. However, one of these studies found that species richness was not affected by the number of pesticide applications in the year of study, only in the previous three years, and another of the studies also found that vineyards managed with reduced insecticide and herbicide application had a similar species richness of moths to conventionally managed vineyards. Two replicated studies (including one randomized, controlled study and one site comparison study) in the UK and Germany found that unfertilized grassland had a similar species richness of butterflies and moths, but greater species richness of specialist moths, to fertilized grassland. POPULATION RESPONSE (9 STUDIES) Abundance (9 studies): Six studies (including one replicated study, one controlled study, one randomized study, four site comparison studies, and one systematic review) in Europe, the UK, Germany, Mexico and Switzerland found that crop edges, farms, a hay meadow, coffee plantations and agricultural landscapes managed with less frequent, reduced or no pesticide, insecticide, fungicide, herbicide, fertilizer or unspecified chemical input (sometimes along with other agri-environment scheme options or less intensive management) had a higher abundance of adult butterflies and moths, or caterpillars, than areas with more frequent or conventional chemical applications. However, one of these studies found that abundance was not affected by the number of pesticide applications in the year of study, only in the previous three years, and another of these studies also found that a hay meadow with no herbicide applications had a similar abundance of caterpillars to a meadow where herbicide was used, and a meadow with no fertilizer applications had a lower abundance of caterpillars than a meadow where fertilizer was applied in one of two sampling sessions. Three replicated studies (including two randomized, controlled studies and one site comparison study) in the UK, Germany and the USA found that unfertilized grassland and replanted Douglas fir stands with limited or no herbicide applications had a similar abundance of adult butterflies and caterpillars, and adult moths, to fertilized grassland and stands with more herbicide applications. BEHAVIOUR (1 STUDY) Use (1 study): One replicated, site comparison study in Germany found that unfertilized or lightly fertilized grasslands were preferred to heavily fertilized grasslands by 7 out of 58 species of moth, but 12 of 58 species preferred more heavily fertilized grasslands. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3897https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3897Tue, 09 Aug 2022 13:43:37 +0100Collected Evidence: Collected Evidence: Replant native vegetation Eleven studies evaluated the effects on butterflies and moths of replanting native vegetation. Five studies were in the USA, two were in New Zealand, and one was in each of Switzerland, Mexico, Ecuador and Brazil. COMMUNITY RESPONSE (5 STUDIES) Community composition (3 studies): One replicated, site comparison study in Ecuador found that native trees planted within recently abandoned pasture and secondary shrubland had a similar community composition of butterflies and moths after 7–8 years, but a subset of communities found on native trees planted within pine plantations, or on saplings regenerating naturally within pristine forest. One replicated, site comparison study in Brazil found that 12–14-year-old replanted and naturally regenerating forests had a different butterfly community to both grazed pasture and remnant forest. One site comparison study in Mexico found that a replanted forest had a different community composition of caterpillars to a naturally regenerating forest. Richness/diversity (5 studies): Four of five site comparison studies (including four replicated studies) in New Zealand, Mexico, Ecuador, Brazil and the USA found that replanted native shrubs, grasses, non-woody broadleaved plants (forbs) and trees had a similar species richness or diversity of butterflies, caterpillars and flower-visiting insects (including butterflies and moths) to vineyards, pasture, naturally regenerating and remnant forests, and remnant prairies. However, one of these studies also found that the species richness of butterflies in replanted native shrubs and grasslands was lower than in remnant native habitat. The fifth study found that, after 7–8 years, native trees planted in pine plantations had a greater species richness of butterflies and moths than trees planted in recently abandoned pasture, but both had a lower species richness than naturally regenerating saplings within pristine forest. POPULATION RESPONSE (6 STUDIES) Abundance (5 studies): Four of five site comparison studies (including four replicated studies) in New Zealand, Mexico and the USA found that replanted native shrubs, grasses, non-woody broadleaved plants (forbs), trees and translocated bamboo rush had a similar abundance of butterflies, caterpillars and flower-visiting insects (including butterflies and moths), and density of Fred the thread moth caterpillars to vineyards, pasture, naturally regenerating forest, remnant prairies and undisturbed bogs. However, one of these studies also found that replanted native shrubs and grasses had a lower abundance of butterflies than remnant native habitat. The fifth study found that common milkweed planted in meadows had fewer monarch butterfly eggs than milkweed planted in private gardens. Survival (2 studies): Two replicated studies (including one randomized, controlled study and one site comparison study) in the USA found that the survival of common sooty winged skipper and monarch butterfly eggs and caterpillars was similar on planted patches of lamb’s-quarters of different sizes, and on common milkweed planted in meadows or private gardens. Condition (1 study): One replicated, site comparison study in New Zealand found that Fred the thread moth caterpillars in translocated bamboo rush plants were a similar size to caterpillars in undisturbed bogs. BEHAVIOUR (3 STUDIES) Use (3 studies): Three studies in the USA and Switzerland reported that planted patches of silver lupine, prairie violet and bladder senna were used by wild mission blue and Iolas blue butterflies, and translocated regal fritillaries, for at least three or 4–10 years after planting. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3933https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3933Sat, 13 Aug 2022 14:09:04 +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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