Collected Evidence: Collected Evidence: Introduce mated females to small populations to improve genetic diversityOne trial in Brazil showed that genetic diversity can be maintained in small isolated populations of stingless bees Melipona scutellaris by regularly introducing inseminated queens.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F56https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F56Thu, 20 May 2010 15:23:26 +0100Collected Evidence: Collected Evidence: Introduce nest boxes stocked with solitary bees We have captured no evidence for the effects of introducing nest boxes stocked with solitary bees on farmland wildlife. '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%2F81https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F81Mon, 24 Oct 2011 21:17:25 +0100Collected Evidence: Collected Evidence: Introduce legislation to control the use of hazardous substances We found no studies that evaluated the effects of introducing legislation to control the use of hazardous substances on bat populations. ‘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%2F1015https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1015Fri, 20 Dec 2013 17:51:23 +0000Collected Evidence: Collected Evidence: Introduce leaf litter to forest stands We found no evidence for the effect of introducing leaf litter to introduce beneficial soil biota on planted trees. '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%2F1161https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1161Wed, 18 May 2016 15:41:27 +0100Collected Evidence: Collected Evidence: Introduce nurse plants (without planting peatland vegetation) We found no studies that evaluated the effects of introducing nurse plants on naturally colonizing, focal peatland vegetation. ‘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%2F1816https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1816Tue, 28 Nov 2017 08:44:02 +0000Collected Evidence: Collected Evidence: Introduce nurse plants (to aid focal peatland plants) Three studies evaluated the effects, on peatland vegetation, of introducing nurse plants to aid focal peatland plants. Two studies were in bogs. One was in a tropical peat swamp. Survival (1 study): One replicated, paired, controlled study in Malaysia reported that planting nurse trees had no effect on survival of planted peat swamp tree seedlings (six species). Cover (2 studies): Two replicated, randomized, paired, controlled, before-and-after studies in bogs in the USA and Canada found that planting nurse herbs had no effect on cover, after 2–3 years, of other planted vegetation (mosses/bryophytes, vascular plants or total cover). Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1830https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1830Tue, 28 Nov 2017 08:52:11 +0000Collected Evidence: Collected Evidence: Introduce certification for bat-friendly crop harvesting regimes We found no studies that evaluated the effects of introducing certification for bat-friendly crop harvesting regimes on bat populations. ‘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%2F1954https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1954Tue, 04 Dec 2018 12:23:48 +0000Collected Evidence: Collected Evidence: Introduce guidelines for sustainable cave development and use We found no studies that evaluated the effects of introducing guidelines for sustainable cave development and use on bat populations. ‘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%2F1996https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1996Wed, 05 Dec 2018 12:54:19 +0000Collected Evidence: Collected Evidence: Introduce economic incentives to encourage sustainable fishing We found no studies that evaluated the effects of introducing economic incentives to encourage sustainable fishing on marine fish populations.  ‘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%2F2811https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2811Fri, 05 Feb 2021 10:03:40 +0000Collected Evidence: Collected Evidence: Introduce legislation to prohibit or restrict the use of fishing gear types or methods that are harmful to mammals We found no studies that evaluated the effects of introducing legislation to prohibit or restrict the use of fishing gear types or methods that are harmful to mammals on marine and freshwater mammal populations. ‘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%2F2831https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2831Fri, 05 Feb 2021 16:05:04 +0000Collected Evidence: Collected Evidence: Introduce fishing gear exchange programmes to encourage fishers to use gear that reduces unwanted catch of mammals We found no studies that evaluated the effects of introducing fishing gear exchange programmes to encourage fishers to use gear that reduces unwanted catch of mammals on marine and freshwater mammal populations. ‘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%2F2834https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2834Fri, 05 Feb 2021 16:07:26 +0000Collected Evidence: Collected Evidence: Introduce fragments of non-woody plants: freshwater wetlands Five studies evaluated the effects, on vegetation, of introducing fragments of emergent, non-woody plants to freshwater wetlands. Three studies were in the USA. Two studies were in one marsh in Australia, but used different experimental set-ups. VEGETATION COMMUNITY   VEGETATION ABUNDANCE Overall abundance (2 studies): Two replicated, randomized, paired, controlled, before-and-after studies in a floodplain marsh in Australia found that plots planted with wick grass Hymenachne acutigluma had similar overall vegetation cover to unplanted plots after one year. One of the studies continued for longer, and found that planted plots had greater overall vegetation cover than unplanted plots after three years. Herb abundance (1 study): One replicated, randomized, paired, controlled, before-and-after study in a floodplain marsh in Australia found that plots planted with wick grass Hymenachne acutigluma had similar overall sedge/grass cover to unplanted plots after one year. Individual species abundance (4 studies): Four studies quantified the effect of this action on the abundance of individual plant species. For example, of two replicated, randomized, paired, controlled, before-and-after studies in a floodplain marsh in Australia, one found that wick grass Hymenachne acutigluma was more frequent and had greater cover, after 1–3 years, in plots where its runners had been planted than where they had not been planted. The other study reported that wick grass cover was present, with approximately 1% cover, in 5 of 10 plots where its runners had been planted. This study monitored vegetation one year after planting. VEGETATION STRUCTURE   OTHER Germination/emergence (1 study): One replicated, randomized, paired, controlled study in a floodplain marsh in Australia found that planting wick grass Hymenachne acutigluma had no significant effect on the germination rate of invasive mimosa Mimosa pigra over three years. Survival (5 studies): Two replicated studies planted sedge Carex fragments into freshwater wetlands in the USA. One study reported 38–79% survival of planted tubers over one growing season, whilst the other study reported 0–73% survival of planted rhizomes after 1–9 months. One replicated study in a tidal freshwater marsh in the USA reported that 6–31% of planted California bulrush Schoenoplectus californicus rhizomes had produced shoots after three months. For two other species, all planted rhizomes died within three months. Two replicated, randomized, paired, controlled, before-and-after studies in a floodplain marsh in Australia reported absence of planted wick grass Hymenachne acutigluma from 17–50% of plots after one year. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3260https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3260Sat, 10 Apr 2021 13:28:02 +0100Collected Evidence: Collected Evidence: Introduce fragments of non-woody plants: brackish/saline wetlands Three studies evaluated the effects, on vegetation, of introducing fragments of emergent, non-woody plants to brackish/saline wetlands. Two studies were in one bog in Canada. One study was in China. VEGETATION COMMUNITY   VEGETATION ABUNDANCE Overall abundance (2 studies): Two replicated, paired, controlled, before-and-after studies in salt-contaminated bogs in Canada found that plots planted with rhizomes or sown with fragments of salt marsh herbs had similar overall vegetation biomass, after one year, to plots that had not been planted or sown. Herb abundance (1 study): One replicated, paired, controlled, before-and-after studies in salt-contaminated bogs in Canada found that plots sown with fragments of salt marsh herbs had greater overall cover of the introduced species, after one year, to unsown plots. However, biomass of the introduced species did not significantly differ between sown and unsown plots. Individual species abundance (2 studies): Two replicated studies (one also before-and-after) in brackish/saline wetlands in Canada and China simply quantified the abundance of herb species, over one year or growing season after planting herb fragments. VEGETATION STRUCTURE   OTHER Germination/emergence (1 study): One replicated study on a tidal flat in China reported that at least 25% of bulrush Scirpus mariqueter corms (bulb-like organs) produced shoots within the first growing season after planting. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3261https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3261Sat, 10 Apr 2021 13:28:14 +0100Collected Evidence: Collected Evidence: Introduce fragments of trees/shrubs: freshwater wetlands One study evaluated the effects, on vegetation, of introducing tree/shrub fragments to freshwater wetlands. The study was in the USA. VEGETATION COMMUNITY   VEGETATION ABUNDANCE   VEGETATION STRUCTURE   OTHER            Survival (1 study): One study in a floodplain swamp clearing in the USA reported 12% overall survival of planted unrooted tree cuttings over two years. For two of four species, no monitored seedlings survived. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3262https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3262Sat, 10 Apr 2021 13:28:25 +0100Collected Evidence: Collected Evidence: Introduce fragments of trees/shrubs: brackish/saline wetlandsWe found no studies that evaluated the effects, on vegetation, of introducing tree/shrub fragments to brackish/saline wetlands.   ‘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%2F3263https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3263Sat, 10 Apr 2021 13:28:45 +0100Collected Evidence: Collected Evidence: Introduce nurse plants to aid focal non-woody plants: freshwater wetlands Two studies evaluated the effects, on vegetation, of introducing nurse plants to freshwater wetlands planted with emergent, non-woody plants. Both studies were on the same site in the USA, but used different experimental set-ups. VEGETATION COMMUNITY   VEGETATION ABUNDANCE Characteristic plant abundance (1 study): One replicated, randomized, paired, controlled, before-and-after study in an experimental wet basin in the USA found that sowing potential nurse plants alongside target sedge meadow species reduced the density of the target species overall, and of target grass-like species. Nurse plant addition sometimes affected the abundance of target forbs, depending on the presence of an invasive species and addition of sawdust to plots. Individual species abundance (2 studies): Two replicated, randomized, paired, controlled, before-and-after studies in wet basins in the USA quantified the effect of this action on the abundance of individual plant species. One study reported that sowing potential nurse plants typically had no significant effect on – and sometimes reduced – the biomass of sown porcupine sedge Carex hystericina, after 1–2 growing seasons. The other study reported varying effects of potential nurse plants on the abundance of individual target plant species, depending on factors such as diversity of the nurse crop and addition of sawdust to plots. VEGETATION STRUCTURE   OTHER Germination/emergence (1 study): One replicated, randomized, paired, controlled study in an experimental wet basin in the USA found that the presence of a high-diversity nurse crop reduced the germination rate of sown sedge meadow species. A low-diversity nurse crop had no significant effect on their germination rate. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3324https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3324Sun, 11 Apr 2021 12:42:28 +0100Collected Evidence: Collected Evidence: Introduce nurse plants to aid focal non-woody plants: brackish/saline wetlands One study evaluated the effects, on vegetation, of introducing nurse plants to brackish/saline wetlands planted with emergent, non-woody plants. The study was in the USA. VEGETATION COMMUNITY   VEGETATION ABUNDANCE   VEGETATION STRUCTURE   OTHER Germination/emergence (1 study): One replicated, controlled study in an estuary in the USA reported that planting nurse plants had no effect on germination of sown arrowgrass Triglochin concinna. No seedlings were found around nurse plants or on bare sediment. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3325https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3325Sun, 11 Apr 2021 12:42:44 +0100Collected Evidence: Collected Evidence: Introduce nurse plants to aid focal trees/shrubs: freshwater wetlandsWe found no studies that evaluated the effects, on vegetation, of introducing nurse plants to freshwater wetlands planted with trees/shrubs.   ‘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%2F3326https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3326Sun, 11 Apr 2021 12:43:00 +0100Collected Evidence: Collected Evidence: Introduce nurse plants to aid focal trees/shrubs: brackish/saline wetlands One study evaluated the effects, on vegetation, of introducing nurse plants to brackish/saline wetlands planted with trees/shrubs. The study was in the USA. VEGETATION COMMUNITY   VEGETATION ABUNDANCE   VEGETATION STRUCTURE   OTHER Survival (1 study): One replicated, controlled study on a mudflat in the USA found that planting black mangrove Avicennia germinans seedlings into created stands of saltwort Batis maritima did not clearly affect their survival, over seven weeks, compared to planting into bare mud. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3327https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3327Sun, 11 Apr 2021 12:43:09 +0100Collected Evidence: Collected Evidence: Introduce legislation to control the use of hazardous substances We found no studies that evaluated the effects on reptile populations of introducing legislation to control the use of hazardous substances. ‘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%2F3560https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3560Wed, 08 Dec 2021 14:46:27 +0000Collected Evidence: Collected Evidence: Introduce fishing gear exchange programs to encourage fishers to use gear that reduces unwanted catch of reptiles We found no studies that evaluated the effects on reptile populations of introducing fishing gear exchange programs to encourage fishers to use gear that reduces unwanted catch of reptiles. ‘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%2F3620https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3620Thu, 09 Dec 2021 13:30:36 +0000Collected Evidence: Collected Evidence: Introduce fishing permit/licence or charter schemes We found no studies that evaluated the effects of introducing fishing permit/licence or charter schemes on marine fish populations.   ‘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%2F3816https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3816Fri, 27 May 2022 08:40:24 +0100Collected Evidence: Collected Evidence: Introduce gear exchange programs We found no studies that evaluated the effects of introducing gear exchange programmes on marine fish populations.   ‘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%2F3828https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3828Fri, 27 May 2022 09:42:22 +0100Collected Evidence: Collected Evidence: Introduce legislation to control the use of hazardous substances We found no studies that evaluated the effects on butterflies and moths of introducing legislation to control the use of hazardous substances. ‘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%2F3892https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3892Tue, 09 Aug 2022 13:02:21 +0100Collected Evidence: Collected Evidence: Introduce mated females to increase genetic diversity We found no studies that evaluated the effects on butterflies and moths of introducing mated females to increase genetic diversity. ‘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%2F3912https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3912Wed, 10 Aug 2022 14:57:39 +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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