Taxocenosis of snakes in the middle plateau region of Rio Grande do Sul, Brazil.

摘要

The present study was conducted on the Brigada Farm (28 degrees 14'39 '' S, 52 degrees 14'42 '' W), Passo Fundo, middle plateau region of Rio Grande do Sul. The objective of the Study was to provide data regarding the richness and abundance of snakes and to compare sampling methods. The study was carried out in two areas, i.e., forest and Field, between January 2001 and March 2003. Data were collected using the following methods: time-constrained search (TCS), occasional encounters by local collectors (OEC), occasional encounters by the team (OET), and by pitfall traps (PT). Using the four methods, 19 snake species belonging to three families (Colubridae, Elapidae and Viperidae) were recorded, and 284 individuals were collected, including 128 by OEC, 36 by TICS, 112 by PT, and 8 by OET. Taking the results of all four methods into account, the three most abundant species were Thamnodynastes strigatus (Gunther, 1858) (16.9%), Echinanthera cyanopleura (Cope, 1885) (15.2%) and Bothrops alternatus Dumeril, Bibron & Dumeril, 1854 (13.4%). The Study of this taxocenosis reveals important characteristics of the ecology of snakes and may contribute to future conservation studies in this area.