Diversity of saproxylic Coleoptera in Great Smoky Mountains National Park

A study of saproxylic beetles was conducted during 2006 and 2007 in Great Smoky Mountains National Park, Tennessee, USA. Six sites, three each in primary and secondary forests were sampled. Emergence chambers were used to collect beetles from dead wood of two sizes (fine=2.5-7.0 cm diameter, coarse=8.0-20.0 cm diameter) and three decay classes from each site. Primary forest sites had a significantly higher volume of CWD than secondary sites. During two years a total of 5692 adult Coleoptera specimens representing 50 families, 226 genera, and 275+ species were collected with emergence chambers. Samples (three each) of leaf litter and CWD decay class 5 were collected at each site during fall and spring, resulting in the collection of 4263 adult Coleoptera specimens in 143+ genera. During summer 2007 flight intercept traps (FIT) were used to collect beetles at one primary and one secondary forest site resulting in the collection of 2472 adult Coleoptera specimens. Preliminary results include: 1) the collection of numerous saproxylic beetle species that are presumed to be rare, many species not previously reported from the park, and several undescribed species; 2) conclusive evidence that leaf litter and CWD decay class 5 have distinctly different beetle communities; 3) and data showing that short term FITs are a poor collection method for saproxylic beetles, but does yield beetle species not collected from litter or emergent from wood.