The influence of abiotic factors on the availability of prey and on the diet of the most abundant snake species in the middle plateau region of Rio Grande do Sul was studied in two areas: forest and field. Snakes captured using time-constrained search, occasional encounters and pitfall traps and snakes deposited in the reptile collection of the University of Passo Fundo were studied. The feeding guilds of the six most abundant species were recorded: anurophagous (n = 2: Echinanthera cyanopleura (Cope, 1885) and Thamnodynates cf. strigatus (Günther, 1858)); rodent-eating (n = 1: Bothrops alternatus Duméril, Bibron & Duméril, 1854); molluscophagous (n = 1: Tomodon dorsatus Duméril, Bibron & Duméril, 1854) and generalist (n = 2: Liophis poecilogyrus (Wied-Neuwied, 1825) and Philodryas patagoniensis (Girard, 1858)). Among the abiotic factors analyzed, snake abundance was associated with maximum temperature (R² = 0.66) and showed no significant association with rainfall. Amphibian abundance showed a positive association with rainfall (R² = 0.54) and was not significantly associated with minimum temperature. Snake abundance was not correlated with the abundance of amphibians or rodents.
Feeding; diet; guilds
