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 other food sources to replace bat meat We found no studies that evaluated the effects of introducing other food sources to replace bat meat 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%2F1976https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1976Tue, 04 Dec 2018 18:24:57 +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 or enforce legislation to prevent ponds and streams from being contaminated by toxins We found no studies that evaluated the effects of introducing or enforcing legislation to prevent ponds and streams from being contaminated by toxins 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%2F2012https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2012Wed, 05 Dec 2018 16:29:43 +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 organisms to control problematic plants: freshwater marshes One study evaluated the effects, on vegetation, of introducing organisms (other than large vertebrate grazers) to control problematic plants in freshwater marshes. The study was in the USA. It involved introducing plants to compete with problematic plants. VEGETATION COMMUNITY Overall richness/diversity (1 study): One replicated, randomized, paired, controlled study in canarygrass-invaded wet meadows in the USA found that plots planted with upland vegetation (after mowing and applying herbicide) had greater overall plant species richness than untreated plots, after 1–3 growing seasons. VEGETATION ABUNDANCE Native/non-target abundance (1 study): One replicated, randomized, paired, controlled study in canarygrass-invaded wet meadows in the USA found that plots planted with upland vegetation (after mowing and applying herbicide) typically had greater cover of unplanted native vegetation than untreated plots, after 1–3 growing seasons. VEGETATION STRUCTURECollected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3128https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3128Mon, 05 Apr 2021 11:55:51 +0100Collected Evidence: Collected Evidence: Introduce organisms to control problematic plants: brackish/salt marshesWe found no studies that evaluated the effects, on vegetation, of introducing organisms (other than large vertebrate grazers) to control problematic plants in brackish/salt marshes.   ‘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%2F3129https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3129Mon, 05 Apr 2021 11:56:07 +0100Collected Evidence: Collected Evidence: Introduce organisms to control problematic plants: freshwater swamps One study evaluated the effects, on vegetation, of introducing organisms (other than large vertebrate grazers) to control problematic plants in freshwater swamps. The study was in the USA. It involved introducing plants to compete with problematic plants. VEGETATION COMMUNITY Overall richness/diversity (1 study): One replicated, randomized, controlled study in a petunia-invaded floodplain swamp in the USA found that plots planted with wetland herbs had greater overall plant species richness than unplanted plots, over the year after planting. Native/non-target richness/diversity (1 study): The same study found that planted plots had greater native plant species richness than unplanted plots, over the year after planting. VEGETATION ABUNDANCE   VEGETATION STRUCTURECollected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3130https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3130Mon, 05 Apr 2021 11:56:19 +0100Collected Evidence: Collected Evidence: Introduce organisms to control problematic plants: brackish/saline swampsWe found no studies that evaluated the effects, on vegetation, of introducing organisms (other than large vertebrate grazers) to control problematic plants in brackish/saline swamps.   ‘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%2F3131https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3131Mon, 05 Apr 2021 11:56:34 +0100Collected Evidence: Collected Evidence: Introduce nurse plants: freshwater marshesWe found no studies that evaluated the effects, on naturally colonizing vegetation, of introducing nurse plants to restore or create freshwater marshes.   ‘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%2F3252https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3252Sat, 10 Apr 2021 13:03:49 +0100Collected Evidence: Collected Evidence: Introduce nurse plants: brackish/salt marshesWe found no studies that evaluated the effects, on naturally colonizing vegetation, of introducing nurse plants to restore or create brackish/salt marshes.   ‘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%2F3253https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3253Sat, 10 Apr 2021 13:04:09 +0100Collected Evidence: Collected Evidence: Introduce nurse plants: freshwater swampsWe found no studies that evaluated the effects, on naturally colonizing vegetation, of introducing nurse plants to restore or create freshwater swamps.   ‘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%2F3254https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3254Sat, 10 Apr 2021 13:04:24 +0100Collected Evidence: Collected Evidence: Introduce nurse plants: brackish/saline swamps One study evaluated the effects, on naturally colonizing vegetation, of introducing nurse plants to restore or create brackish/saline swamps. The study was in India. VEGETATION COMMUNITY   VEGETATION ABUNDANCE   VEGETATION STRUCTURE Height (1 study): One study on an estuarine mudflat in India reported that the average height of mangrove propagules trapped by nurse grasses increased by 21–90% (depending on the species) over the first month after establishment. OTHER Germination/emergence (1 study): One study on an estuarine mudflat in India reported that 60–80% (depending on the species) of mangrove propagules trapped by nurse grasses developed into seedlings. Saltmarsh grasses trapped 1,200–1,372 mangrove propagules/m2/week, approximately 1–2 years after they were planted. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3255https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3255Sat, 10 Apr 2021 13:04:30 +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 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
What Works 2021 cover

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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