Life Sciences Commons^™

Evaluation Of Ecological Risk To Populations Of A Threatened Plant From An Invasive Biocontrol Insect, Svata M. Louda, Tatyana A. Rand, A. E. Arnett, A. S. Mcclay, K. Shea, K. Mceachern

Svata M. Louda Publications

Controversy exists over estimation of ecological risk in biological control. At present, the risk to the rare, federally listed Pitcher’s thistle (Cirsium pitcheri) in North America from Rhinocyllus conicus, a biological control weevil now feeding on many native thistles, is unknown. We hypothesized that quantification of host specificity and potential phenological overlap between insect and plant would improve assessment of the magnitude of risk. In laboratory host specificity tests, we found no significant difference in R. conicus feeding or oviposition preference between the rare C. pitcheri and the targeted exotic weed (Carduus nutans) or between …