Collected Evidence: Collected Evidence: Practise ‘wildlife gardening’ Four studies evaluated the effects of practising wildlife gardening on butterflies and moths. Two were in the UK and one was in each of France and the USA. COMMUNITY RESPONSE (1 STUDY) Richness/diversity (1 study): One replicated, paired, controlled study in the USA found that areas with reduced frequency weeding had a similar species richness of adult butterflies compared to areas with conventional weeding. POPULATION RESPONSE (3 STUDIES) Abundance (3 studies): Two replicated studies (including one paired, controlled study) in the UK and the USA found that increasing the number and age of potted nettle plants in gardens and weeding less frequently did not increase abundance of butterflies, all caterpillars and caterpillars and eggs of four target species. One replicated, site comparison study in France found that gardens where insecticides and herbicides were not used and where there were natural features had a higher abundance of butterflies, but gardens where fungicides and snail pellets were not used had a lower abundance of butterflies. BEHAVIOUR (2 STUDIES) Use (2 studies): One replicated study in the UK reported that caterpillars only occasionally used potted nettle plants in gardens. One site comparison study in the UK found that planted buddleia and marjoram were visited by adult butterflies and moths more frequently than other plant species. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3834https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3834Mon, 04 Jul 2022 15:12:24 +0100Collected Evidence: Collected Evidence: Protect or restore brownfield or ex-industrial sites We found no studies that evaluated the effects of protecting or restoring brownfield or ex-industrial sites on butterflies and moths. ‘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%2Fconservationevidencejournal.com%2Factions%2F3835https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3835Mon, 04 Jul 2022 15:24:10 +0100Collected Evidence: Collected Evidence: Protect greenfield sites or undeveloped land in urban areas Two studies evaluated the effects of protecting greenfield sites or undeveloped land in urban areas on butterflies and moths. One study was in Singapore and the other was in Mexico. COMMUNITY RESPONSE (2 STUDIES) Richness/diversity (2 studies): Two site comparison studies (including one replicated study) in Singapore and Mexico found that protected native forest and grassland in urban areas had a higher species richness of butterflies than urban parks or non-native Eucalyptus plantations. POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3836https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3836Mon, 04 Jul 2022 15:25:46 +0100Collected Evidence: Collected Evidence: Establish “green infrastructure” in urban areas One study evaluated the effects of establishing “green infrastructure in urban areas on butterflies and moths. This study was in Taiwan. COMMUNITY RESPONSE (1 STUDY) Richness/diversity (1 study): One replicated, site comparison study in Taiwan found that green roofs had a lower species richness of butterflies than urban parks. POPULATION RESPONSE (1 STUDY) Abundance (1 study): One replicated, site comparison study in Taiwan found that green roofs had a lower abundance of butterflies than urban parks, but the abundance was higher on older green roofs with more nectar plant species in a larger area. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3837https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3837Mon, 04 Jul 2022 15:32:09 +0100Collected Evidence: Collected Evidence: Plant trees to reduce temperatures in cities We found no studies that evaluated the effects of planting trees to reduce temperatures in cities on butterflies and moths. ‘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%2Fconservationevidencejournal.com%2Factions%2F3838https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3838Mon, 04 Jul 2022 15:35:33 +0100Collected Evidence: Collected Evidence: Apply ecological compensation for developments Two studies evaluated the effects of on butterflies and moths of applying ecological compensation for developments. One was in the USA and the other was in Australia. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): One study in Australia reported that a population of purple copper butterfly caterpillars translocated from a development site to an area of compensatory and retained habitat increased in number over three years. BEHAVIOUR (1 STUDY) Use (1 study): One site comparison study in the USA reported that an area of lupines transplanted from a development site was used by a similar number of Karner blue butterflies to an area with no transplanted lupines. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3839https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3839Mon, 04 Jul 2022 15:40:59 +0100Collected Evidence: Collected Evidence: Require developers to complete Environmental Impact Assessments when submitting planning applications We found no studies that evaluated the effects on butterflies and moths of requiring developers to complete Environmental Impact Assessment when submitting planning applications. ‘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%2Fconservationevidencejournal.com%2Factions%2F3840https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3840Mon, 04 Jul 2022 15:41:59 +0100Collected 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%2Fconservationevidencejournal.com%2Factions%2F3841https%3A%2F%2Fconservationevidencejournal.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%2Fconservationevidencejournal.com%2Factions%2F3842https%3A%2F%2Fconservationevidencejournal.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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