Pitfall traps

A probabilistic risk assessment (PRA) deals with many types of uncertainties. In addition to the uncertainties associated with the model itself and model input, there is also the meta-uncertainty about whether the entire PRA process has been performed properly. Employment of sophisticated mathematical and statistical methods may easily convey the false impression of accuracy, especially when numerical results are presented with a high number of significant figures. But those who produce PR As, and those who evaluate them, should exert caution there are many possible pitfalls, traps, and potential swindles that can arise. Because of the potential for generating seemingly correct results that are far from the intended model of reality, it is imperative that the PRA practitioner carefully evaluates not only model input data but also the assumptions used in the PRA, the model itself, and the calculations inherent within the model. This chapter presents information on performing PRA in a manner that will minimize the introduction of errors associated with the PRA process. 

Pitfall traps Pitfall, probe, or pitfall cone (PC) traps are physical traps that are placed at surface level or buried inside bulk grain. The pitfall trap consists of a plastic jar with a mesh screen over the top. The trap is placed inside the grain or on the surface layer of the bulk grain so that insects... 

Dowdy, A.K. and Mullen, M.A. 1998. Multiple stored-product insect pheromone use in pitfall traps. 

Reed, C.R., Wright, V.F., Mize, T.W., Pedersen, J.R., and Brockschmidt, EJ. 1991. Pitfall traps and grain samples as indicators of insects in farm-stored wheat. J. Econ. Entomol. 84, 1381-1387. 

Monitored compoimd-spedfic data were the survival rates of adults and nestlings within the treated area (effects imder field conditions). Furthermore, residues in/on food items (arthropod prey) within treated fields (term C within the ETE-calculation) were analyzed in arthropod samples collected with suitable methods (e.g., pitfall traps, inventory spray) from treated fields. 

For collecting and inventorying ground-dwelling insects and other arthropods, pitfall traps together with Barber traps (Barber 1931) are the most effective and long-established methods, for which a considerable body of literature exists (e.g. Houseweart et al., 1979 Borges and Brown, 2003 Woodcock, 2005). They consist... 

Borges, P. A. and Brown, V. K. 2003. Estimating species richness of arthropods in Azorean pastures the adequacy of suction sampling and pitfall trapping. Graellsta, 59 7-24. 

Woodcock, B. A. (2005). Pitfall trapping in ecological studies. In Insect sampling in forest ecosystems, S. Leather (ed). Oxford Blackwell, pp. 37-57. 

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