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%2Fwww.conservationevidence.com%2Factions%2F1039https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1039Fri, 03 Jul 2015 15:18:58 +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%2Fwww.conservationevidence.com%2Factions%2F1041https%3A%2F%2Fwww.conservationevidence.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%2Fwww.conservationevidence.com%2Factions%2F1042https%3A%2F%2Fwww.conservationevidence.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%2Fwww.conservationevidence.com%2Factions%2F1043https%3A%2F%2Fwww.conservationevidence.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%2Fwww.conservationevidence.com%2Factions%2F1044https%3A%2F%2Fwww.conservationevidence.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%2Fwww.conservationevidence.com%2Factions%2F1045https%3A%2F%2Fwww.conservationevidence.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%2Fwww.conservationevidence.com%2Factions%2F1046https%3A%2F%2Fwww.conservationevidence.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%2Fwww.conservationevidence.com%2Factions%2F1047https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1047Fri, 03 Jul 2015 15:21:15 +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%2Fwww.conservationevidence.com%2Factions%2F1049https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1049Fri, 03 Jul 2015 15:21:38 +0100Collected Evidence: Collected Evidence: Amphibians: Identify and breed a similar species to refine husbandry techniques prior to working with target species Two small, replicated interlinked studies in Brazil found that working with a less-threatened surrogate species of frog first to establish husbandry interventions promoted successful breeding of a critically endangered species of frog. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1862https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1862Thu, 18 Jan 2018 16:03:54 +0000Collected Evidence: Collected Evidence: Amphibians: Allow temperate amphibians to hibernate No evidence was captured for the effects of allowing temperate amphibians to hibernate. '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%2F1868https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1868Fri, 19 Jan 2018 08:59:37 +0000Collected Evidence: Collected Evidence: Amphibians: Allow amphibians from highly seasonal environments to have a period of dormancy during a simulated drought period No evidence was captured for the effects of allowing amphibians from highly seasonal environments to have a period of dormancy during a simulated drought period. '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%2F1869https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1869Fri, 19 Jan 2018 09:02:52 +0000Collected Evidence: Collected Evidence: Amphibians: Manipulate adult density within the enclosure No evidence was captured for the effects of manipulating adult density within the enclosure. '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%2F1878https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1878Fri, 19 Jan 2018 10:57:57 +0000Collected Evidence: Collected Evidence: Amphibians: Manipulate sex ratio within the enclosure One replicated study in Australia found that frogs only bred once sex ratios were manipulated, along with playing recorded mating calls and moving frogs into an indoor enclosure which allowed temporary flooding, and had various types of organic substrate. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1879https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1879Fri, 19 Jan 2018 11:00:23 +0000Collected Evidence: Collected Evidence: Amphibians: Allow female mate choice One replicated study in Australia found that frogs only bred after females carrying eggs were introduced to males, sex ratios were manipulated, recorded mating calls were played, and after being moved to an indoor enclosure which allowed temporary flooding and had various types of organic substrates. One replicated, before-and-after study in Australia found that clutch size of frogs increased when female mate choice was provided, alongside playing recorded mating calls, sexes being separated in the non-breeding periods, and allowing females to increase in weight before breeding. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1882https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1882Fri, 19 Jan 2018 13:50:02 +0000Collected Evidence: Collected Evidence: Amphibians: Formulate adult diet to reflect nutritional composition of wild foods No evidence was captured for the effects of formulating diet to reflect nutritional composition of wild foods. '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%2F1884https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1884Fri, 19 Jan 2018 13:53:40 +0000Collected Evidence: Collected Evidence: Amphibians: Increase caloric intake of females in preparation for breeding One replicated, before-and-after study in Australia found that clutch size of frogs increased when females increased in weight before breeding, as well as having mate choice, recorded mating calls, and sexes being separated in the non-breeding periods. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1888https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1888Fri, 19 Jan 2018 14:36:09 +0000Collected Evidence: Collected Evidence: Amphibians: Formulate larval diets to improve development or survival to adulthood One randomized, replicated, controlled study in the USA found that tadpoles had a higher body mass and reached a more advanced developmental stage when fed a control diet (rabbit chow and fish food) or freshwater algae, compared to those fed pine or oak pollen. Tadpoles fed only pine or oak pollen did not undergo metamorphosis. One randomised, replicated study in Portugal found that tadpoles reared on a diet containing 46% protein had higher growth rates, survival and body weights at metamorphosis compared to diets containing less protein. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1889https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1889Fri, 19 Jan 2018 14:42:14 +0000Collected Evidence: Collected Evidence: Amphibians: Leave infertile eggs at spawn site as food for egg-eating larvae No evidence was captured for the effects of leaving infertile eggs at spawn site as food for egg-eating larvae. '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%2F1890https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1890Fri, 19 Jan 2018 14:49:45 +0000Collected Evidence: Collected Evidence: Amphibians: Manipulate humidity to improve development or survival to adulthood No evidence was captured for the effects of manipulating humidity to improve development or survival to adulthood. '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%2F1891https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1891Fri, 19 Jan 2018 14:52:17 +0000Collected Evidence: Collected Evidence: Amphibians: Manipulate quality and quantity of enclosure lighting to improve development or survival to adulthood No evidence was captured for the effects of manipulating quality and quantity of lighting to improve development or survival to adulthood. '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%2F1892https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1892Fri, 19 Jan 2018 14:54:25 +0000Collected Evidence: Collected Evidence: Amphibians: Manipulate temperature of enclosure to improve development or survival to adulthood One replicated study in Spain found that salamander larvae had higher survival rates when reared at lower temperatures. One replicated study in Germany found that the growth rate and development stage reached by harlequin toad tadpoles was faster at a higher constant temperature rather than a lower and varied water temperature. One replicated study in Australia found that frog tadpoles took longer to reach metamorphosis when reared at lower temperatures. One replicated, controlled study in Iran found that developing eggs reared within a temperature range of 12-25°C had higher survival rates, higher growth rates and lower abnormalities than those raised outside of that range. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1893https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1893Fri, 19 Jan 2018 15:02:07 +0000Collected Evidence: Collected Evidence: Amphibians: Manipulate larval density within the enclosure A replicated study in the USA found that reducing larval density of spotted salamanders increased larval survival and body mass. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1894https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1894Fri, 19 Jan 2018 15:05:40 +0000Collected Evidence: Collected Evidence: Amphibians: Allow adults to attend their eggs No evidence was captured for the effects of allowing adults to attend their eggs. '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%2F1895https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1895Fri, 19 Jan 2018 15:07:03 +0000Collected Evidence: Collected Evidence: Amphibians: Freeze sperm or eggs for future useFor summarised evidence see Smith, R.K. and Sutherland, W.J. (2014) Amphibian conservation: Global evidence for the effects of interventions. Exeter, Pelagic Publishing.   Key messages and summaries are available here: http://www.www.conservationevidence.com/actions/876Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1899https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1899Fri, 19 Jan 2018 15:11:58 +0000
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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