Observations on Problems with Using Funnel Traps to Sample Semi-Aquatic Snakes

摘要

Funnel traps have been shown to be an effective method for sampling snakes in many different aquatic habitats (Fitch 1999; Greene et al. 1999; Karns et al. 2000; Keck 1994). However, any technique can have biases which need to be considered when choosing an appropriate sampling method. In this note I report problems encountered using funnel traps to sample snakes. These problems include: 1) predation upon trapped Banded Watersnakes (Nerodiafasciatafasciata) by Eastern Cottonmouths (Agkistrodon piscivorus piscivorus); 2) potentially biased sex ratios ofN.fasciata and A. piscivorus; and 3) predation upon trapped snakes by red imported fire ants (Solenopsis invicta).