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Individual study: Common frog and European toad tadpole survival, mass and behaviour was similar to untreated pools when low and high disinfectant doses of Virkon S, but not bleach were added

Published source details

Schmidt B.R., Geiser C., Peyer N., Keller N. & vonRütte M. (2009) Assessing whether disinfectants against the fungus Batrachochytrium dendrobatidis have negative effects on tadpoles and zooplankton. Amphibia-Reptilia, 30, 313-319


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Sterilize equipment when moving between amphibian sites Amphibian Conservation

A randomized, replicated, controlled study in 30 artificial pools in Switzerland (Schmidt et al. 2009) found that Virkon S disinfectant did not affect survival, mass or behaviour of common frog Rana temporaria and common toad Bufo bufo tadpoles, but bleach did. Survival did not differ between Virkon treatments for frogs (untreated: 70–100%; low dose: 90–100%; high dose: 40–100%) or toads (untreated: 90–100%; low dose: 100%; high dose: 70–100%). All tadpoles died within 1–2 days in high dose bleach. Survival was significantly lower in low dose bleach than untreated water for frogs (20–100 vs 70–100%) and toads (40–100 vs 90–100%). Frog tadpole mass was significantly higher in low dose bleach (0.5–0.6 g) than other treatments (0.3–0.5 g). Toad tadpole mass did not differ (0.2–0.4 g). The proportion of tadpoles feeding did not differ significantly for frogs (0.4–0.9) or toads (0.6–0.9). Local leaves, phytoplankton, zooplankton and a snail were added to artificial pools (80 L). Disinfectants (bleach 2%; Virkon 10 g/L) that would be used for boots and field equipment were applied to pools once a week at high (0.04 L) or low doses (0.004 L), with 0.060 L or 0.096 L of water respectively. Water was added as the control. Treatments were replicated five times and assigned randomly to tubs. Ten frog and toad tadpoles were added to each treatment.