Natural History and Taxonomy of the Carabidae
June 22-25, 2008 • Oak Lake Field Station, Brookings Co, South Dakota
In partnership with the Midwest Institute for Biological Control
Jonathan Lundgren, USDA-ARS, Brookings SD
Kirk Larsen, Luther College, IA
Foster Purrington, Ohio State University, OH
Don Weber, USDA-ARS, Beltsville, MD
Kip Will, Essig Museum of Entomology, Berkeley, CA
Coupling hands-on activities and discussions with lecture-style presentations by world experts, we trained students in the taxonomy, feeding ecology, defensive capabilities, community patterns, and activity cycles of the Carabidae.
Taxonomy (Purrington, Will, Lundgren)
A major challenge facing students interested in working with ground beetles is identifying specimens of this diverse and sometimes cryptic group. Students were introduced to pertinent keys and terminology that are used to identify the most commonly encountered genera of Carabidae. A worldwide perspective of the phylogeny of the group was also presented.
Collecting (Weber, Lundgren)
The strengths and weaknesses of different collecting and sampling techniques were discussed by instructors, and the implications of sampling regimens on research outcomes were presented. Activity patterns of Carabidae (especially diel cycles) were a major focus of this unit, and an activity on emplacing and observing sentinel prey during the day and night was conducted.
Feeding Ecology of the Carabidae (Lundgren, Weber)
Carabidae are a diverse group, best appreciated for their ability to consume insect prey. But the reality is that we don’t know the full dietary breadth for even a single species, and this has major implications for studying and using carabids in biological control. Current methodologies for diagnosing feeding behavior of carabids were discussed extensively, and the importance of non-prey foods (especially seeds) to the life histories of Carabidae was highlighted. A laboratory on gut dissection and microscopic analysis of feeding contents was conducted.
Defensive Chemistry of Carabidae (Will)
Defensive secretions, best known in the bombardier beetles, are an important aspect of the natural history (and phylogeny) of Carabidae. Students dissected the defensive glands from carabid specimens, and collected the secretions for chemical analysis, after listening to a lecture on the current knowledge of the defensive chemistry of the group.
Habitat Management (Larsen)
Because of their abundance and diversity, carabid communities are often used as bio-indicators of various environmental qualities and habitat restoration practices. Their sensitivity to environmental disturbance and various habitat traits have resulted in very different communities within managed and natural habitats. A round-table discussion of these community patterns and how to study and analyze them was directed among the students.