Collected Evidence: Collected Evidence: American bullfrog control: Biological control using native predators One replicated, controlled study conducted in Belgium found the introduction of the northern pike led to a strong decline in bullfrog tadpole numbers.  Collected Evidencehttps%3A%2F%2Fconservationevidence.com%2Factions%2F1039https%3A%2F%2Fconservationevidence.com%2Factions%2F1039Fri, 03 Jul 2015 15:18:58 +0100Collected Evidence: Collected Evidence: American bullfrog control: Biological control of co-occurring beneficial species No evidence was captured on the effects of removing co-occurring beneficial species on the control of American bullfrogs. '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%2Fconservationevidence.com%2Factions%2F1040https%3A%2F%2Fconservationevidence.com%2Factions%2F1040Fri, 03 Jul 2015 15:19:09 +0100Collected Evidence: Collected Evidence: American bullfrog control: Habitat modification No evidence was captured on the effects of habitat modification on the control of American bullfrogs. '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%2Fconservationevidence.com%2Factions%2F1041https%3A%2F%2Fconservationevidence.com%2Factions%2F1041Fri, 03 Jul 2015 15:19:26 +0100Collected Evidence: Collected Evidence: American bullfrog control: Draining ponds and altering the length of time for which the pond contains water No evidence was captured on the effects of draining ponds or altering the length of time for which ponds contain water on the control of American bullfrogs. '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%2Fconservationevidence.com%2Factions%2F1042https%3A%2F%2Fconservationevidence.com%2Factions%2F1042Fri, 03 Jul 2015 15:20:07 +0100Collected Evidence: Collected Evidence: American bullfrog control: Pond destruction No evidence was captured on the effects of pond destruction on the control of American bullfrogs. '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%2Fconservationevidence.com%2Factions%2F1043https%3A%2F%2Fconservationevidence.com%2Factions%2F1043Fri, 03 Jul 2015 15:20:20 +0100Collected Evidence: Collected Evidence: American bullfrog control: Fencing No evidence was captured on the effects of fencing on the control of American bullfrogs. '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%2Fconservationevidence.com%2Factions%2F1044https%3A%2F%2Fconservationevidence.com%2Factions%2F1044Fri, 03 Jul 2015 15:20:33 +0100Collected Evidence: Collected Evidence: American bullfrog control: Direct removal of adults One replicated study in Belgium found catchability of adult bullfrogs in small shallow ponds using one double fyke net for 24 h to be very low. One small study in the USA found that bullfrog adults can be captured overnight in a single trap floating on the water surface. One replicated, controlled study in the USA found that bullfrog populations rapidly rebounded following intensive removal of the adults. One before-and-after study in France found a significant reduction in the number of recorded adults and juveniles following the shooting of metamorphosed individuals before reproduction, when carried out as part of a combination treatment.  Collected Evidencehttps%3A%2F%2Fconservationevidence.com%2Factions%2F1045https%3A%2F%2Fconservationevidence.com%2Factions%2F1045Fri, 03 Jul 2015 15:20:46 +0100Collected Evidence: Collected Evidence: American bullfrog control: Direct removal of juveniles One replicated study in Belgium found double fyke nets were effective in catching bullfrog tadpoles in small shallow ponds. One before-and-after study in France found a significant reduction in the number of recorded adults and juveniles following the removal of juveniles by trapping, when carried out as part of a combination treatment.  Collected Evidencehttps%3A%2F%2Fconservationevidence.com%2Factions%2F1046https%3A%2F%2Fconservationevidence.com%2Factions%2F1046Fri, 03 Jul 2015 15:20:59 +0100Collected Evidence: Collected Evidence: American bullfrog control: Collection of egg clutches Despite reference to removal of egg clutches in some studies using bilge pumps or nets, no evidence was captured on the effects of egg collection on American bullfrogs. '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%2Fconservationevidence.com%2Factions%2F1047https%3A%2F%2Fconservationevidence.com%2Factions%2F1047Fri, 03 Jul 2015 15:21:15 +0100Collected Evidence: Collected Evidence: American bullfrog control: Application of a biocide One replicated, controlled study in the USA found a number of chemicals killed American bullfrogs, including caffeine (10% solution), chloroxylenol (5% solution), and a combined treatment of Permethrin (4.6% solution) and Rotenone (1% solution).  Collected Evidencehttps%3A%2F%2Fconservationevidence.com%2Factions%2F1048https%3A%2F%2Fconservationevidence.com%2Factions%2F1048Fri, 03 Jul 2015 15:21:26 +0100Collected Evidence: Collected Evidence: American bullfrog control: Public education No evidence was captured on the effects of public education on the control of American bullfrogs. '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%2Fconservationevidence.com%2Factions%2F1049https%3A%2F%2Fconservationevidence.com%2Factions%2F1049Fri, 03 Jul 2015 15:21:38 +0100Collected Evidence: Collected Evidence: Brown and black bullheads: Application of a biocide A study in the UK reported that use of a piscicide containing rotenone achieved eradication of black bullhead. A study in the USA found that rotenone successfully eradicated black bullhead, but one of two ponds required two separate doses.  Collected Evidencehttps%3A%2F%2Fconservationevidence.com%2Factions%2F1050https%3A%2F%2Fconservationevidence.com%2Factions%2F1050Wed, 07 Oct 2015 10:41:27 +0100Collected Evidence: Collected Evidence: Asian clams: Drain the invaded water body No evidence was captured for the use of dewatering as a management tool for 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%2Fconservationevidence.com%2Factions%2F1110https%3A%2F%2Fconservationevidence.com%2Factions%2F1110Tue, 13 Oct 2015 14:41:00 +0100Collected 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%2Fconservationevidence.com%2Factions%2F1111https%3A%2F%2Fconservationevidence.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%2Fconservationevidence.com%2Factions%2F1112https%3A%2F%2Fconservationevidence.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%2Fconservationevidence.com%2Factions%2F1113https%3A%2F%2Fconservationevidence.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%2Fconservationevidence.com%2Factions%2F1114https%3A%2F%2Fconservationevidence.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%2Fconservationevidence.com%2Factions%2F1115https%3A%2F%2Fconservationevidence.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%2Fconservationevidence.com%2Factions%2F1116https%3A%2F%2Fconservationevidence.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%2Fconservationevidence.com%2Factions%2F1117https%3A%2F%2Fconservationevidence.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%2Fconservationevidence.com%2Factions%2F1118https%3A%2F%2Fconservationevidence.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%2Fconservationevidence.com%2Factions%2F1119https%3A%2F%2Fconservationevidence.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%2Fconservationevidence.com%2Factions%2F1120https%3A%2F%2Fconservationevidence.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%2Fconservationevidence.com%2Factions%2F1121https%3A%2F%2Fconservationevidence.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%2Fconservationevidence.com%2Factions%2F1122https%3A%2F%2Fconservationevidence.com%2Factions%2F1122Tue, 13 Oct 2015 15:10:26 +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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