Collected Evidence: Collected Evidence: Asian clams: Exposure to parasites No evidence was captured for the use of parasite exposure to control Asian clams. '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%2F1111https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1111Tue, 13 Oct 2015 14:42:01 +0100Collected Evidence: Collected Evidence: Asian clams: Exposure to disease-causing organisms No evidence was captured for the use of exposure to disease-causing organisms for the control of Asian clams. '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%2F1112https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1112Tue, 13 Oct 2015 14:42:57 +0100Collected Evidence: Collected Evidence: Asian clams: Reduce oxygen in the water A controlled laboratory study conducted in the USA found that Asian clams were resistant to extreme very low levels of oxygen, irrespective of water temperature or length of immersion in the test conditions.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1113https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1113Tue, 13 Oct 2015 14:45:11 +0100Collected Evidence: Collected Evidence: Asian clams: Change pH of the water No evidence was captured for the use of pH adjustment to control Asian clams. '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%2F1114https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1114Tue, 13 Oct 2015 14:46:57 +0100Collected Evidence: Collected Evidence: Asian clams: Change salinity of the water A controlled, replicated laboratory study conducted in the USA found that Asian clams were killed (100% mortality) when exposed to high salinities (18-34‰).  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1115https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1115Tue, 13 Oct 2015 14:50:28 +0100Collected Evidence: Collected Evidence: Asian clams: Change temperature of the water A controlled laboratory study in the USA found that temperatures of 36°C or higher killed Asian clams within or after four days.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1116https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1116Tue, 13 Oct 2015 14:53:06 +0100Collected Evidence: Collected Evidence: Asian clams: Use gas-impermeable barriers A controlled study in North America found that placing gas-impermeable barriers across the bottom of the lake (several small fabric covers or one large cover) significantly reduced the abundance of Asian clams.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1117https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1117Tue, 13 Oct 2015 14:55:26 +0100Collected Evidence: Collected Evidence: Asian clams: Add chemicals to the water A replicated laboratory study in the USA found that dosing with the biocides chlorine, potassium and copper killed Asian clams. A controlled, replicated laboratory study and a controlled, replicated field study in the USA found that higher concentrations of chlorine and bromine, delivered at higher temperatures, shortened the time required to kill the Asian clams. A controlled field-based trial in Spanish irrigation systems showed that fat-coated particles called BioBullets could kill 100% of the Asian clams within pipes. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1118https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1118Tue, 13 Oct 2015 14:59:51 +0100Collected Evidence: Collected Evidence: Asian clams: Clean equipment A study in Portugal found that mechanical removal and regular cleaning of industrial pipes or addition of a sand filter were effective methods of permanently removing or reducing numbers of Asian clams, respectively.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1119https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1119Tue, 13 Oct 2015 15:03:29 +0100Collected Evidence: Collected Evidence: Asian clams: Mechanical removal A replicated, controlled, before-and after trial in North America found that suction dredging reduced Asian clam densities within the sediment by 96% over two weeks and that the reduction persisted for a year. A replicated, controlled, before-and-after field trial in Ireland found that three types of dredges were equally effective at removing Asian clams, resulting in a biomass reduction ranging from 74% to >95%, and an density reduction ranging from 65% to 95%. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1120https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1120Tue, 13 Oct 2015 15:07:16 +0100Collected Evidence: Collected Evidence: Asian clams: Remove by hand No evidence was captured on the use of hand removal as a tool for managing Asian clams. '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%2F1121https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1121Tue, 13 Oct 2015 15:08:11 +0100Collected Evidence: Collected Evidence: Asian clams: Public awareness and education No evidence was captured on the use of raising public awareness and education as tools for managing Asian clams. '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%2F1122https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1122Tue, 13 Oct 2015 15:10:26 +0100Collected Evidence: Collected Evidence: Floating pennywort: Biological control using co-evolved, host specific herbivores A replicated laboratory and field study in South America found that the South American weevil caused more feeding lesions on floating pennywort than on any other plant species, but field results found that the weevil did not reduce floating pennywort biomass.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1123https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1123Tue, 13 Oct 2015 15:27:21 +0100Collected Evidence: Collected Evidence: Floating pennywort: Biological control using native herbivores No evidence was captured on biological control of floating pennywort using native herbivores. '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%2F1124https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1124Tue, 13 Oct 2015 15:28:43 +0100Collected Evidence: Collected Evidence: Floating pennywort: Biological control using fungal-based herbicides No evidence was captured on biological control of floating pennywort using fungal-based herbicides. '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%2F1125https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1125Tue, 13 Oct 2015 15:29:58 +0100Collected Evidence: Collected Evidence: Floating pennywort: Physical removal A study in Western Australia found that following a two-week program of physical removal of floating pennywort, the rate of growth exceeded the rate of removal. A study in the UK, found that removal using a mechanical digger and monthly picking by hand greatly reduced the cover of floating pennywort but did not completely eradicate it. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1126https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1126Tue, 13 Oct 2015 15:33:08 +0100Collected Evidence: Collected Evidence: Floating pennywort: Chemical control using herbicides A controlled, replicated study in the UK found that the herbicide 2,4-D amine applied at 4.2 kg/ha achieved near to 100% mortality, compared with the herbicide glyphosate applied at 2.2 kg active ingredient/ha (without an adjuvant) which achieved  negligible mortality. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1127https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1127Tue, 13 Oct 2015 15:36:51 +0100Collected Evidence: Collected Evidence: Floating pennywort: Combination treatment using herbicides and physical removal A before-and-after study in Western Australia found that a combination of cutting followed by glyphosate chemical treatment, removed floating pennywort. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1128https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1128Tue, 13 Oct 2015 15:39:22 +0100Collected Evidence: Collected Evidence: Floating pennywort: Use of hydrogen peroxide A controlled, replicated pilot study in The Netherlands, found that hydrogen peroxide sprayed on potted floating pennywort plants resulted in curling and transparency of the leaves when applied at the highest tested concentration (30%), but this was still not sufficient to kill the plant.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1129https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1129Tue, 13 Oct 2015 15:41:57 +0100Collected Evidence: Collected Evidence: Floating pennywort: Use of liquid nitrogen No evidence was captured on the use of liquid nitrogen for control of floating pennywort. '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%2F1130https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1130Tue, 13 Oct 2015 15:43:21 +0100Collected Evidence: Collected Evidence: Floating pennywort: Flame treatment A controlled, replicated, pilot experiment in 2010 in The Netherlands, found that flame treatments of 1, 2 or 3 seconds had a significantly negative and progressive impact on floating pennywort, and a 3 second repeat treatment after 11 days proved fatal. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1131https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1131Tue, 13 Oct 2015 15:46:00 +0100Collected Evidence: Collected Evidence: Floating pennywort: Excavation of banks No evidence was captured on the effects of excavation of banks using a sod-cutter or ‘turf-cutter’ to remove floating pennywort. '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%2F1132https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1132Tue, 13 Oct 2015 15:46:58 +0100Collected Evidence: Collected Evidence: Floating pennywort: Environmental control (e.g. shading, reduced flow, reduction of rooting depth, or dredging) No evidence was captured on the potential for environmental control of floating pennywort using shading, increased flow, reduction of rooting depth to below 1 metre, or dredging. '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%2F1133https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1133Tue, 13 Oct 2015 15:48:34 +0100Collected Evidence: Collected Evidence: Floating pennywort: Public education No evidence was captured on the impact of education programmes on control of floating pennywort. '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%2F1134https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1134Tue, 13 Oct 2015 15:49:48 +0100Collected Evidence: Collected Evidence: Water primrose: Biological control using co-evolved, host specific herbivores A controlled, replicated field study in China, found a flea beetle caused heavy feeding destruction when added to field cages containing prostrate water primrose seedlings, and was specific to the prostrate water primrose and Indian toothcup. A replicated, before-and-after field study in the USA found that introduction of flea beetles to a pond significantly reduced the abundance of large-flower primrose-willow. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1135https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1135Tue, 13 Oct 2015 16:03:06 +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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