Baseline egg load of southern pine beetle parasitoid complex

Egg load of newly emerged adult parasitoids of the southern pine beetle, Dendroctonus frontalis Zimmermann (Coleoptera: Scolytidae), was examined. Infested bark was collected from D. frontalis infestations in southwestern Arkansas (Clark and Montgomery counties; 1995), the Bankhead National Forest in Alabama (1999), and the Talladega National Forest in Alabama (1998-2000) between June and September of each collection year. Newly emerged parasitoid females were dissected and numbers of mature and immature eggs counted. There was no significant difference in number of eggs within a species and between parasitoids from the Bankhead National Forest compared with those from the Talladega National Forest in Alabama in 1999. There were differences in number of eggs within a species between years at the same location. Dendroctonus frontalis parasitoids in the family Pteromalidae (Hymenoptera) had the most mature eggs, followed by Braconidae (Hymenoptera) and Eurytomidae (Hymenoptera). Within the D. frontalis parasitoids in the family Pteromalidae, Dinotiscus dendroctoni (Ashmead) and Heydenia unica Cook and Davis had more mature eggs than did Roptrocerus xylophagorum Ratzeburg. Within the D. frontalis parasitoids in the family Braconidae, Meteorus hypophloei Cushman females contained the most mature eggs, followed by Dendrosoter sulcatus Muesebeck, Spathius pallidus Ashmead, and Coeloides pissodis (Ashmead). These data constitute a foundation for defining baseline egg load of the D. frontalis parasitoid complex

Effect of Investigator Disturbance in Experimental Forensic Entomology: Succession and Community Composition

Carrion insect succession studies have historically used repeated sampling of single or a few carcasses to produce data, either weighing the carcasses, removing a qualitative subsample of the fauna present, or both, on every visit over the course of decomposition and succession. This study, conducted in a set of related experimental hypotheses with two trials in a single season, investigated the effect that repeated sampling has on insect succession, determined by the number of taxa collected on each visit and by community composition. Each trial lasted at least 21 days, with daily visits on the first 14 days. Rat carcasses used in this study were all placed in the field on the same day, but then either sampled qualitatively on every visit (similar to most succession studies) or ignored until a given day of succession, when they were sampled qualitatively (a subsample) and then destructively sampled in their entirety. Carcasses sampled on every visit were in two groups: those from which only a sample of the fauna was taken and those from which a sample of fauna was taken and the carcass was weighed for biomass determination. Of the carcasses visited only once, the number of taxa in subsamples was compared to the actual number of taxa present when the carcass was destructively sampled to determine if the subsamples adequately represented the total carcass fauna. Data from the qualitative subsamples of those carcasses visited only once were also compared to data collected from carcasses that were sampled on every visit to investigate the effect of the repeated sampling. A total of 39 taxa were collected from carcasses during the study and the component taxa are discussed individually in relation to their role in succession. Number of taxa differed on only one visit between the qualitative subsamples and the actual number of taxa present, primarily because the organisms missed by the qualitative sampling were cryptic (hidden deep within body cavities) or rare (only represented by very few specimens). There were no differences discovered between number of taxa in qualitative subsamples from carcasses sampled repeatedly (with or without biomass determinations) and those sampled only a single time. Community composition differed considerably in later stages of decomposition, with disparate communities due primarily to small numbers of rare taxa. These results indicate that the methods used historically for community composition determination in experimental forensic entomology are generally adequate