Carrion Beetles (Coleoptera: Silphidae) of Northeastern Iowa: A Comparison of Baits for Sampling

Carrion beetles (Coleoptera: Silphidae) were inventoried over a 8-week period from June into August of 1996 at 10 sites in 4 counties of extreme northeastern Iowa. Carrion preference and relative abundance of carrion beetles were studied by use of non-lethal pitfall traps constructed from large plastic plant pots and baited with aged fish, beef liver, chicken, or piglets. A total of 3,183 carrion beetles were collected, representing 11 different species. The most commonly encountered species of carrion beetles in northeastern Iowa included Necrophila americana (71.5%) and Oiceoptoma novaboracense (18.5%). When comparing baits, chicken and fish attracted the greatest number of carrion beetle species, individual beetles, and the most diverse assemblage of beetles as compared to beef liver and piglets. No American Burying Beetles (Nicrophorus americanus), a federally-listed endangered species last documented in Northeastern Iowa in 1921, were found. We propose aged chicken as the most useful bait for future surveys of carrion beetles