We have uploaded a range of files informding about ergosterol and bacteria levels on leaf litter (LeafMicrobes.xlsx); the feces production, leaf consumption and legnth development of tadpoles during the study and among the two experimental phases as detailed in the mansucript (FecesFeedingLength.xlxs); composition of fatty acids in tadpoles and leaf litter (NFLA.xlxs); metamophoses event (Metamorphosis.xlsx)

Paper abstract as submitted:

Biodiversity is under pressure world-wide, with amphibians being particularly threatened. Stressors related to human activity, such as chemicals, are contributing to this decline. It remains, however, unclear whether chemicals exhibiting a fungicidal activity could indirectly affect tadpoles, that depend on microbially conditioned leaf litter as food source. The indirect effect of fungicides (sum concentration of a fungicide mixture composed of azoxystrobin, carbendazim, crybrodinil, quinoxifen and tebuconcazole: 100 µg/L) on tadpoles was assessed relative to leaf litter colonised by microbes in absence of fungicides (control) and a worst case scenario, that is leached leaf litter without microbial colonisation. The quality of leaf litter as food for tadpoles of the European common frog (Rana temporaria) was characterised through neutral lipid fatty acid profiles and microbial sum parameters and verified by sublethal responses in tadpoles (i.e. feeding rate, feces production, growth and fatty acid composition). Fungicides changed the nutritious quality of leaf litter likely through alterations in leaves’ neutral lipid fatty acid profiles (i.e., changes in some physiologically important highly unsaturated fatty acids reached more than 200%) in combination with a potential adsorption onto leaves during conditioning. These changes were reflected by differences in the development of tadpoles ultimately resulting in an earlier start of metamorphosis. Our data provide a first indication that fungicides potentially affect tadpole development indirectly through bottom-up effects. This pathway is so far not addressed in fungicide environmental risk assessment and merits further attention.

The methods are detailed in the paper at Ecology and Evolution, which is published open access. 

LeafMicrobes.xlsx
the file contains data on ergosterol and bacteria associated with leaf litter normalised to leaf mass (sie line 1 of the respective sheets)

FecesFeedingLength.xlsx
the file contains data on feces production, leaf consumption and length development of tadpoles in both experimental phases. The first two variabels are normalised to the lengths of the respective tadpoles and scaled to a day. The length is reported in mm.

NLFA.xlsx
the file reports mean concentrations of individual fatty acids in leaf litter and tadpoles together with confidence intervals of the respective treatment.