Collected Evidence: Collected Evidence: Ponto-Caspian gammarids: Change water pH A controlled laboratory study from the UK found that lowering the pH of water did not kill invasive killer shrimp.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1093https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1093Tue, 13 Oct 2015 13:41:18 +0100Collected Evidence: Collected Evidence: Ponto-Caspian gammarids: Dewater (dry out) the habitat A replicated, controlled laboratory study from Poland found that lowering water levels in sand killed three species of invasive freshwater shrimp, although one species required water content levels of 4% and below before it was killed.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1094https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1094Tue, 13 Oct 2015 13:44:55 +0100Collected Evidence: Collected Evidence: Ponto-Caspian gammarids: Add chemicals to the water A controlled laboratory study in the UK found that iodine solution, acetic acid, Virkon S and sodium hypochlorite added to freshwater killed invasive killer shrimp, but were considered impractical for field application. Methanol, citric acid, urea, hydrogen peroxide and sucrose did not kill invasive killer shrimp when added to freshwater.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1095https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1095Tue, 13 Oct 2015 13:48:43 +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 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: 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: 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: 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: 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: Water primrose: Physical removal A study in the USA found that hand pulling and raking water primrose failed to reduce its abundance, whereas hand-pulling from the margins of a pond eradicated a smaller population of water primrose. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1138https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1138Tue, 13 Oct 2015 16:11:51 +0100Collected Evidence: Collected Evidence: Crassula helmsii: Use hydrogen peroxide to control plants One controlled study in the UK using tank trials found that hydrogen peroxide did not control Crassula helmsii.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1281https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1281Tue, 12 Jul 2016 08:42:23 +0100Collected Evidence: Collected Evidence: Crassula helmsii: Use dyes to reduce light levels One replicated, controlled study in the UK found that applying aquatic dye, along with other treatments, did not reduce coverage of Crassula helmsii. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1293https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1293Tue, 12 Jul 2016 09:32:38 +0100Collected Evidence: Collected Evidence: Crassula helmsii: Decontamination to prevent further spread One controlled, replicated container study in the UK found that submerging Crassula helmsii in hot water led to higher mortality than drying out plant fragments or a control.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1308https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1308Tue, 12 Jul 2016 10:57:56 +0100Collected Evidence: Collected Evidence: Crassula helmsii: Use a combination of control measures One before-and-after study at a single pond in the UK found covering Crassula helmsii with carpet, followed by treatment with the herbicide glyphosate, killed 80% of the plant. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1313https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1313Tue, 12 Jul 2016 11:04:35 +0100Collected Evidence: Collected Evidence: Primates: Present food in water (including dishes and ponds) One replicated, before-and-after study in the USA found that when exposed to water-filled troughs, monkeys were more active and increased their use of tools.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1320https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1320Wed, 12 Oct 2016 15:01:04 +0100Collected Evidence: Collected Evidence: Primates: Present food dipped in food colouring One before-and-after study in the USA found that when food was dipped in food colouring juvenile and adult orangutans ate more and took less time to consume it.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1322https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1322Wed, 12 Oct 2016 15:12:41 +0100Collected Evidence: Collected Evidence: Primates: Present food items whole instead of processed One before-and-after study in the USA found that when macaques were presented with whole foods instead of chopped foods the amount consumed and time spent feeding increased.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1323https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1323Wed, 12 Oct 2016 15:33:43 +0100Collected Evidence: Collected Evidence: Primates: Present feeds at different crowd levels One before-and-after study in the USA found that when smaller crowds were present foraging and object use in chimpanzees increased. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1324https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1324Wed, 12 Oct 2016 15:38:41 +0100Collected Evidence: Collected Evidence: Primates: Provide live vegetation in planters for foraging One replicated, before-and-after study in the USA reported that chimpanzees spent more time foraging when provided with planted rye grass and scattered sunflower seeds compared to browse and grass added to the enclosure with their normal diet.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1327https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1327Thu, 13 Oct 2016 08:18:54 +0100Collected Evidence: Collected Evidence: Parrot’s feather: Water level drawdown One replicated, randomized, controlled laboratory study in the USA found that water removal to expose plants to drying during the summer led to lower survival of parrot’s feather plants than exposing plants to drying during the winter. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1585https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1585Fri, 20 Oct 2017 13:07:37 +0100Collected Evidence: Collected Evidence: Parrot’s feather: Biological control using plant pathogens One study in South Africa found that parrot’s feather plants survived after being treated with a strain of the bacterium Xanthomonas campestris. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1601https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1601Fri, 20 Oct 2017 15:05:32 +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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