Collected Evidence: Collected Evidence: Practise wildlife gardening A site comparison study in one city in the UK found more species of bumblebee in domestic city gardens with lower intensity of management, a measure reflecting the tidiness of the garden and the use of garden pesticides. Solitary bees were not affected by this measure.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2Tue, 18 May 2010 07:40:30 +0100Collected Evidence: Collected Evidence: Protect brownfield sites We have captured no evidence for the effects of interventions to protect brownfield sites from insensitive re-development. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.    Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3Tue, 18 May 2010 14:57:41 +0100Collected Evidence: Collected Evidence: Paint wind turbines to increase their visibilityA single ex situ experiment found that thick black stripes running across a wind turbine’s blades made them more conspicuous to an American kestrel than control (unpatterned) blades, but that other designs were less visible, or indistinguishable from controls.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F258https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F258Wed, 18 Jul 2012 13:40:49 +0100Collected Evidence: Collected Evidence: Mowing roadside vergesA single replicated, controlled study in the USA found that more ducks nested on unmown roadside verges, but that over four years, nesting success on unmown verges fell to below that on mown verges.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F259https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F259Thu, 19 Jul 2012 13:19:48 +0100Collected Evidence: Collected Evidence: Foster eggs or chicks of woodpeckers with wild conspecifics Three studies from the USA found that red-cockaded woodpecker Picoides borealis chicks fostered to conspecifics had high fledging rates. One small study found that fostered chicks survived better than chicks translocated with their parents.    Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F514https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F514Thu, 06 Sep 2012 16:29:20 +0100Collected Evidence: Collected Evidence: Foster eggs or chicks of parrots with wild conspecifics A replicated study from Venezuela found that yellow-shouldered Amazon Amazona barbadensis chicks had high fledging rates when fostered to conspecific nests in the wild. A second replicated study from Venezuela found significantly lower poaching rates of yellow-shouldered Amazons Amazona barbadensis when chicks were moved to foster nests closer to a field base.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F515https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F515Thu, 06 Sep 2012 16:34:58 +0100Collected Evidence: Collected Evidence: Use temperature treatment to reduce chytridiomycosis infection Four of five studies (including four replicated, controlled studies) in Australia, Switzerland and the USA found that increasing enclosure or water temperature to 30–37°C for over 16 hours cured frogs and toads of chytridiomycosis. One found that heat treatment at 30–35°C for 36 hours did not cure northern leopard frogs.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F770https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F770Mon, 19 Aug 2013 16:15:16 +0100Collected Evidence: Collected Evidence: Create walls or barriers to exclude pollutants One controlled study in Mexico found that installing filters across canals to improve water quality and exclude fish increased weight gain in axolotls.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F771https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F771Tue, 20 Aug 2013 15:11:46 +0100Collected Evidence: Collected Evidence: Establish fallowing to reduce parasites/diseaseA study in Scotland recorded lower lice numbers on Atlantic salmon in cages using a fallowing system. Another study in Australia found no difference in mortality from Amoebic Gill Disease in cages where a fallowing system had been used.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1026https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1026Wed, 18 Jun 2014 14:41:41 +0100Collected Evidence: Collected Evidence: Establish fallowing to reduce pollutionA trial in Tasmania found sediment community structure under Atlantic salmon cages became more similar to non- impacted sites over two fallowing cycles.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1027https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1027Wed, 18 Jun 2014 14:45:25 +0100Collected Evidence: Collected Evidence: Crassula helmsii: Use liquid nitrogen to kill plants We found no evidence for the effects of treating Crassula helmsii with liquid nitrogen. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1282https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1282Tue, 12 Jul 2016 08:51:36 +0100Collected Evidence: Collected Evidence: Keep safety distance to habituated animals One before-and-after study in the Democratic Republic of Congo found that most reintroduced chimpanzees survived over five years after being followed from a distance of 5–100 m, alongside other interventions. One controlled study in Malaysia found that the number of reintroduced orangutans declined by 33% over 31 years despite visitors being required to keep a safety distance to the animals, alongside other interventions. One before-and-after study in Rwanda, Uganda and Congo found that numbers of mountain gorillas increased by 168% over 41 years while being observed from a safety distance, alongside other interventions. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1538https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1538Thu, 19 Oct 2017 14:38:23 +0100Collected Evidence: Collected Evidence: Limit time that researchers/tourists are allowed to spend with habituated animals One controlled study in Indonesia found that reintroduced Sumatran orangutans that spent limited time with caretakers acted more similar to wild orangutans than orangutans that spend more time with caretakers, alongside other interventions. One before-and-after study in Rwanda, Uganda and the Democratic Republic of Congo found that numbers of mountain gorillas increased by 168% over 41 years while being visited by researchers and visitors during a restricted amount of time, alongside other interventions. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1539https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1539Thu, 19 Oct 2017 15:12:10 +0100Collected Evidence: Collected Evidence: Build barriers to protect peatlands from the sea We found no studies that evaluated the effects, on peatland vegetation, of building barriers to protect peatlands from seawater damage. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1794https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1794Tue, 28 Nov 2017 08:19:42 +0000Collected Evidence: Collected Evidence: Restore/create peatlands in areas that will be climatically suitable in the future We found no studies that evaluated the effects, on peatland vegetation, of restoring or creating peatlands in areas that will be climatically suitable in the future. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1795https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1795Tue, 28 Nov 2017 08:21:18 +0000Collected Evidence: Collected Evidence: Restore or create forest or woodland Two studies evaluated the effects of restoring forests on bat populations. One study was in Brazil and one in Australia. COMMUNITY RESPONSE (1 STUDY) Richness/diversity (1 study): One site comparison study in Brazil found that a reforested area had significantly lower bat diversity than a native forest fragment. POPULATION RESPONSE (1 STUDY) Abundance (1 study): One replicated, controlled, site comparison study in Australia found that forests restored after mining had significantly higher or similar bat activity (relative abundance) as unmined forests for five of seven bat species. BEHAVIOUR (0 STUDIES)      Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2050https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2050Fri, 07 Dec 2018 12:43:26 +0000Collected Evidence: Collected Evidence: Restore or create grassland One study evaluated the effects of creating grassland on bat populations. The study was in the UK. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): One replicated, paired sites study in the UK found that pipistrelle activity (relative abundance) did not differ between species-rich grassland created on agri-environment scheme farms and improved pasture or crop fields on conventional farms. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2051https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2051Fri, 07 Dec 2018 12:47:28 +0000Collected Evidence: Collected Evidence: Retain buffer zones around core habitat We found no studies that evaluated the effects on mammals of retaining buffer zones around core habitat. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this intervention during our systematic journal and report searches. Therefore, we have no evidence to indicate whether or not the intervention has any desirable or harmful effects.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2562https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2562Tue, 09 Jun 2020 12:46:37 +0100Collected Evidence: Collected Evidence: Use an electric current to deter mammals from fishing gear One study evaluated the effects of using an electric current to deter mammals from fishing gear. The study was in the Fraser River (Canada). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Human-wildlife conflict (1 study): One controlled study in the Fraser River found that using an electric current on a fishing net reduced Pacific harbour seal predation on salmon catches. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2818https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2818Fri, 05 Feb 2021 15:10:45 +0000Collected Evidence: Collected Evidence: Change season/timing of prescribed burning: freshwater marshes One study evaluated the effects, on vegetation, of burning freshwater marshes in different seasons or at different times. The study was in the USA. VEGETATION COMMUNITY Overall richness/diversity (1 study): One replicated, randomized, controlled study in a marsh in the USA found that spring-burned plots had greater plant species richness than summer-burned plots, at the end of the growing season. VEGETATION ABUNDANCE Overall abundance (1 study): One replicated, randomized, controlled study in a marsh in the USA found that spring-burned plots had greater overall vegetation cover than summer-burned plots, at the end of the growing season. Individual species abundance (1 study): The same study reported that the cover and frequency of some individual plant species responded differently to spring vs summer burning. VEGETATION STRUCTURECollected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3074https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3074Fri, 02 Apr 2021 14:45:30 +0100Collected Evidence: Collected Evidence: Use fences or barriers to protect freshwater wetlands planted with trees/shrubs Five studies evaluated the effects, on vegetation, of using fences or barriers to protect freshwater wetlands planted with trees/shrubs. Four studies were in the USA and one was in Australia. VEGETATION COMMUNITY   VEGETATION ABUNDANCE Tree/shrub abundance (1 study): One replicated, paired, controlled study in a floodplain swamp clearing in the USA found that amongst plots sown with tree seeds, fencing to exclude deer had no significant effect on total tree seedling density after three years. VEGETATION STRUCTURE Height (2 studies): One replicated, paired, controlled study in a floodplain swamp clearing in the USA found that amongst plots sown with tree seeds, those also fenced to exclude deer contained taller tree seedlings, after three years, than those left unfenced. One replicated, paired, controlled study in created freshwater wetlands in the USA found that the average height of white cedar Thuja occidentalis saplings typically increased by a similar amount, between two and five years after planting, in plots fenced to exclude deer and plots left unfenced. OTHER Survival (3 studies): One replicated, paired, controlled study in floodplain swamps in Australia reported that planted swamp gum Eucalyptus camphora seedlings had a much higher survival rate, over one year, in plots fenced to exclude mammals than in open plots. Two replicated, paired, controlled studies in freshwater wetlands in the USA reported that exclusion fencing sometimes increased survival of planted tree seedlings but sometimes had no clear or significant effect. This depended on factors such as the season of planting, seedling elevation, and site. Growth (1 study): One replicated, randomized, controlled study in a nutria-invaded wetland in the USA found that planted baldcypress Taxodium distichum seedlings grew more, over one growing season, when protected than when left unprotected. Plastic guards increased height and diameter growth rates. Sticky, insect-repellent oil increased the growth rate for height, but not diameter. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3330https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3330Sun, 11 Apr 2021 13:15:05 +0100Collected Evidence: Collected Evidence: Reduce pesticide, herbicide or fertilizer use We found no studies that evaluated the effects on reptile populations of reducing pesticide, herbicide or fertilizer use. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3585https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3585Wed, 08 Dec 2021 15:33:48 +0000Collected Evidence: Collected Evidence: Plant riparian buffer strips One study evaluated the effects of planting riparian buffer strips on reptile populations. The study was in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (1 STUDY) Use (1 study): One replicated study in the USA found that grassed riparian buffer strips were used by up to five snake species. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3586https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3586Wed, 08 Dec 2021 15:46:10 +0000Collected Evidence: Collected Evidence: Alter mowing regimes on greenspaces and road verges Seven studies evaluated the effects of altering mowing regimes on greenspaces and road verges on butterflies and moths. One study was in each of Finland, the Netherlands, Poland, Germany, the UK, Canada and Sweden. COMMUNITY RESPONSE (3 STUDIES) Richness/diversity (3 studies): Two replicated, paired, controlled studies in Germany and the UK found that less frequently mown or unmown urban greenspaces had a higher species richness and diversity of butterflies and moths than more frequently mown areas. One replicated, site comparison study in Canada found that the management of road verges (and land under power lines) did not affect the species richness of butterflies. POPULATION RESPONSE (4 STUDIES) Abundance (3 studies): Two replicated studies (including one paired, controlled study) in the UK and Canada found that unmown public parks and road verges (and land under power lines) had a higher abundance of all adult butterflies and pearl crescent and northern pearl crescent butterflies than regularly mown areas, but the abundance of other butterflies on the road verges (and under power lines) was similar between mown and unmown areas in the second study. One study in Finland found that roadsides mown in late summer had more ringlet butterflies than those mown in mid-summer. Survival (1 study): One replicated, site comparison study in Poland found that road verges mown less frequently, or later in summer, had fewer dead butterflies killed by traffic than more frequently or earlier mown verges. BEHAVIOUR (2 STUDIES) Use (2 studies): One replicated, site comparison study in Sweden reported that less frequently mown urban grasslands were more frequently occupied by scarce copper butterflies than more frequently mown grasslands. One replicated, randomized, controlled study in the Netherlands found that butterflies were recorded on verges which were mowed once or twice a year and those which were not mowed, but on mowed verges butterflies were only recorded on those where hay was removed. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3841https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3841Mon, 04 Jul 2022 15:45:31 +0100Collected Evidence: Collected Evidence: Plant parks, gardens and road verges with appropriate native species Eight studies evaluated the effects on butterflies and moths of planting parks and gardens with appropriate native species. Seven were in the USA and one was in Germany. COMMUNITY RESPONSE (5 STUDIES) Richness/diversity (5 studies): Three of five replicated studies (including three paired, three controlled and two site comparison studies) in Germany and the USA found that gardens and road verges planted with native species had a greater species richness of butterfly and moth adults and caterpillars than gardens or verges with mixed or exclusively non-native plant species. The other two studies found that the species richness of adult butterflies was similar in areas planted with native or non-native flowers. POPULATION RESPONSE (6 STUDIES) Abundance (4 studies): Two of three replicated studies (including two paired and two controlled studies) in the USA found that gardens planted with native species had a higher abundance of butterfly and moth caterpillars than gardens with mixed or exclusively non-native plant species. The third study found that the abundance of adult butterflies was similar in areas planted with native or non-native flowers. One replicated, randomized, controlled study in the USA found that when taller native milkweed species were planted, they had a higher abundance of monarch butterfly eggs and caterpillars than shorter milkweed species. Survival (2 studies): One of two replicated, site comparison studies in the USA found that the survival of pipevine swallowtail eggs and caterpillars was lower on California pipevine planted in gardens than in natural sites. The other study found that the survival of monarch butterfly caterpillars was similar on common milkweed planted in gardens and meadows. Condition (1 study): One replicated, randomized, controlled study in the USA found that the growth of monarch butterfly caterpillars was similar on eight different native milkweed species. BEHAVIOUR (2 STUDIES) Use (2 studies): One of two replicated, site comparison studies in the USA found that monarch butterfly adults used common milkweed planted in gardens more than milkweed planted in meadows. The other study found that pipevine swallowtail adults used California pipevine planted in gardens less than in natural sites. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3842https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3842Tue, 05 Jul 2022 09:53:23 +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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