Smaniotto N. P., L. F. B. Moreira, J. A. Rivas & C. Strüssmann

Home range size, movement, and habitat use of yellow anacondas (Eunectes notaeus). pp. 159-167 plus Supplementary documents.

Abstract. Movement ecology is an important tool for understanding animal behaviour toward basic needs, as well as to design conservation and management priorities. Animals usually do not move randomly and may prefer certain types of habitats over others. The yellow anaconda (Eunectes notaeus) is one of the largest snakes in South America. However, little is known about its natural history. Here, we present results from a telemetry study to quantify movement patterns and habitat use of eight yellow anacondas in a protected, seasonally flooded area in Midwestern Brazil. Yellow anacondas were associated to small channels with macrophyte stands and bushy vegetation. They moved relatively little (188 m monthly) and had small home range (mean 6.2 ha); they used native pastures and abandoned farmlands with forest patches more than expected by chance. Our results contribute to the understanding of dispersal patterns, habitat choices, and life history of this large aquatic snake and to the body of knowledge needed for management and conservation of its populations and habitats.

Key words. Squamata, Serpentes, Boidae, home range, wetland, landscape ecology, South America.