Sampling Carabid Assemblages With Pitfall Traps: The Madness and the Method

Abstract

We describe a litter-washing technique for collecting quantitative samples of ground-beetles (Carabidae), and compare the results with those from liner extraction by Tullgren funnels and pitfall (rapping. We also compare performance of four types of pitfall traps across five habitats. Carabid species composition from litter washing and funnel extraction was similar but washing revealed higher densities. Large-bodied species predominated in pitfall samples and small-bodied species predominated in litter samples. Uncovered, round pitfall traps yielded generally higher catches than rectangular or covered, round traps but the pattern was not consistent over all species or the five habitats. Ecological studies of carabid populations and assemblages using pitfall traps may be improved if they are both designed and interpreted in light of the biology of the group and with regard to the deficiencies of pitfall trapping as discussed here and elsewhere.

Reverting Conservation Reserve Program Lands to Wheat and Livestock Production: Effects on Ground Beetle (Coleoptera: Carabidae) Assemblages

“…Although pitfall traps are the most widely used devices for capturing ground beetles and other epigeal arthropods, they are not without their flaws. Trap efficiency in capturing ground beetles, the proportion captured to total possible captures, is affected by trap design, individual behavior of species, and type of habitats in which the traps are placed (Greenslade 1964, Halsall and Wratten 1988, Morrill et al 1990, Spence and Niemela 1994. Some habitats restrict the movement of ground beetles, thus 2 habitats may have the same density of ground beetles, but one may be more conducive to beetle movement, and hence catch-ability (Frampton et al 1995, Mauremooto et al 1995.…”

Application of Semiochemicals to Assess the Biodiversity of Subcortical Insects following an Ecosystem Disturbance in a Sub-boreal Forest

“…inside a 1.0 l plastic liner buried in the ground (Spence and Niemelä 1994). Propylene glycol (200 ml; recreational vehicle antifreeze, Peak Co., Northbrook, IL, USA) in the plastic container served as killing agent and preservative for trapped beetles (Weeks and McIntyre 1997).…”

Succession of ground beetle (Coleoptera: Carabidae) communities after windthrow disturbance in a montane Norway spruce forest in the Hrubý Jeseník Mts. (Czech Republic)

“…Ground beetles were sampled using pitfall traps (8 cm in diameter, 15 cm deep, one-third filled with a 4% formaldehyde solution), a standard method used to sample epigeic invertebrates (Spence & Niemelä 1994). In each study stand, 8 traps were installed in a line at a spacing of 10 m. The trap lines were located in the centres of the study stands, and no trap was closer than 10 m from the stand edge.…”