I suppose that carrion (wherever it is placed) will at least be a starting point for succession. There will be flies and pupae possibly attracting predators like Carabidae in further stages of succession. That might well happen with a dead mouse in a pitfall trap, depending on the used liquid. These would be some papers on the succession topic:

Peschke, K., D. Krapf & D. Fuldner (1987): Ecological separation, functional relationships, and limiting resources in a carrion insect community. – Zool. Jahrbuch Systematik 114: 241-265.

Schoenly, K. (1992): A Statistical Analysis of Successional Patterns in Carrion Arthropod Assemblages - Implications for Forensic Entomology and Determination of the Postmortem Interval. - Journal of Forensic Sciences 37 (6): 1489-1513.

Wolff, M., A. Uribe, A. Ortiz & P. Duque (2001): A Preliminary Study of Forensic Entomology in Medellin, Colombia. – Forensic Science International 120 (1-2): 53-59.

Best regards

Armin

Well, necrophagous (or sometimes necrophagous) insects could be attracted by small mammals, reptiles or insects dead in the pitfall trap. But these insects are present in the area surveyed by the pitfall. What is the problem with this? Whether there is a problem with it will depend on what is the thing you want to analyze with pitfall traps (species presence? soil entomofauna biodiversity? Differences among habitats? these three anwsers are not affected wheter a small mammal dead in the trap, buy you can also control the situation using replicates or pseudoreplicates of the pitfall trap in each location and testing if significant differences occur.

Best wishes,

Antonio.

Dear Adela,

carabids are unfortunately very sensitive to conditions they can find in or close to Barber traps. Just presence of fresh formalin/ monoethylen glycol might attract or distract different species (Luff 1968), attractiveness of these preservatives is different in different parts of season (Holopainen 1992) etc. So presence of rotting animals would have similar but likely much stronger consequences. Note that just a presence of living carabid attracts other carabids as noted by Leśniak (1977), so it might be similar with some necrophags.

Overall don't get upset about Barber traps. They have plenty of weaknesses but other methods have other limitations too.

You might have a look at my small review paper in Polish :)) but abstract drawings and references are in English

https://www.researchgate.net/publication/232724777_Strange_fauna_of_Barber_traps?ev=prf_pub

good luck

Article Strange fauna of Barber traps