| Resumo: |
The effectiveness of pitfall traps associated with drift fences to capture amphibians and reptiles in three field studies, in Rio Grande do Sul (extreme southern Brazil), São Paulo (São Paulo, southeastern Brazil), and Amazonas (Amazonas, northern Brazil) is described. At Santa Maria, a total of 2040 amphibians and reptiles were caught in 30 pitfalls (200 L, with drift fence) during 18 months of study (capture efficiencies of 3.78 amphibians and reptiles/pitfall/month and 0.14 snake/pitfall/month). At Itirapina, São Paulo, 1262 amphibians and reptiles were obtained in 72 pitfalls (100 L, with drift fence) during six months (capture efficiencies of 11,9 amphibians and reptiles/pitfall/month and 0,38 snake/pitfall/month). At Rio Pitinga, Amazonas, over 600 amphibians and reptiles were caught in 50 pitfalls (100-150 L, with drift fence) during three months (capture efficiencies of ca. 4.00 amphibians and reptiles/pitfall/month and 0.87 snake/pitfall/month). Capture efficiencies of 1.25 to ~3.92 amphibians and reptiles/pitfall/month were obtained in four other unpublished studies made by other authors in Brazil, all of them using 20-35 L traps, either with or without drift fences. Higher capture efficiencies for snakes were obtained in those studies in which larger containers (100-200 L) were used. The results presented here indicate that pitfall traps are extremely useful to sample amphibians and reptiles in Brazil, especially anurans and lizards. From these results, it is possible to preview the capture of 125 to 1200 amphibians and reptiles with 100 pitfalls during one month, regardless of the size of the pitfalls and sampling design of the trap arrays. The main advantages and disadvantages of the method and detailed guidelines on how to design, install, and use the traps is discussed.
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