A comparison of live versus kill pitfall trapping techniques using various killing agents

Abstract

We compared the efficacies of two arthropod pitfall trapping techniques: live (dry) trapping and kill trapping with three killing agents (water, ethylene glycol, and the recently developed propylene glycol, whose efficacy has not been previously assessed). Kill pitfall traps caught more species than did live pitfalls. Forty‐one species were collected only from kill traps (3 being unique to water, 11 to ethylene glycol, and 8 to propylene glycol), 12 were collected only from live traps, and 32 were collected from both kill and live traps. The same average number of individuals per species was caught for most of those taxa that were collected in both trap types, indicating that better retention of captured arthropods by the killing agent was not responsible for the differences observed in the two pitfall trapping methods. There were no significant differences in captures between propylene and ethylene glycol traps or between water and live traps. Because of species‐specific differences in the efficiencies of live and kill pitfall trapping, cross‐study entomological comparisons made using kill pitfall trapping and live pitfalling may be confounded.

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). The trap was covered with a 100 cm 2 plywood board suspended 4 cm above the trap to minimize flooding and disturbance by animals.…”

Does your preservative preserve? A comparison of the efficacy of some pitfall trap solutions in preserving the internal reproductive organs of dung beetles

“…All preservatives were tested in pitfall traps placed in the fi eld, except for 96% ethanol which was tested in sealed vials in the lab. (Weeks and McIntyre 1997;Schmidt et al 2006;Th omas 2008). Th e reduced preservation eff ect of brine and ethylene glycol was also reported for a study involving carabid beetles (Sasakawa 2007).…”

“…Th ese preservatives were chosen based on their previous use or recommendation as pitfall trap solutions (see Hall 1991;Weeks and McIntyre 1997;Pekar 2002;Perner and Schueler 2004;Norden et al 2005;Schmidt et al 2006;Jud and Schmidt-Entling 2008). Water is also commonly used as a killing agent in pitfall traps but due to its obvious lack of preservative properties it was not tested.…”

“…Pitfall traps have long been recognised as an eff ective and inexpensive technique for sampling arthropods, including Coleoptera (Greenslade and Greenslade 1971;Gist and Crossley 1973;Luff 1975;Newton and Peck 1975;Topping and Sunderland 1992;Weeks and McIntyre 1997). Th e effi ciency of pitfall traps may be infl uenced by aspects of construction, such as shape, size and materials (Luff 1975;Brennan et al 1999); spacing and transect design (Luff 1975;Ward et al 2001;Perner and Schueler 2004;Larsen and Forsyth 2005); and the use of various baits, killing agents, and preservatives (Luff 1968;Greenslade and Greenslade 1971;Weeks and McIntyre 1997;Pekar 2002).…”

“…Th e effi ciency of pitfall traps may be infl uenced by aspects of construction, such as shape, size and materials (Luff 1975;Brennan et al 1999); spacing and transect design (Luff 1975;Ward et al 2001;Perner and Schueler 2004;Larsen and Forsyth 2005); and the use of various baits, killing agents, and preservatives (Luff 1968;Greenslade and Greenslade 1971;Weeks and McIntyre 1997;Pekar 2002). Although various killing agents and preservatives are commonly used in pitfall traps, there is a lack of studies testing the effi cacy of preservative type in preventing the decomposition of collected samples.…”