Deguang Liu, dgliu@ucdavis.edu1, Robert C. Venette, rvenette@fs.fed.us2, Steve Munson, smunson@fs.fed.us, Beverly Bulaon, bbulaon@fs.fed.us3, Mary Louise Flint, mlflint@ucdavis.edu4, and Steven J Seybold, sseybold@fs.fed.us5. (1) University of California, Davis, Entomology, 720 Olive Drive, Suite D, Davis, CA, (2) USDA Forest Service, Northern Research Station, 1561 Lindig St, St. Paul, MN, (3) USDA Forest Service, Forest Health Protection, 19777 GREENLEY ROAD, Sonora, CA, (4) University of California, Entomology, One Shields Ave, Davis, CA, (5) USDA Forest Service, Pacific Southwest Research Station, Chemical Ecology of Forest Insects, 720 Olive Drive, Suite D, Davis, CA
Mediterranean pine engraver, Orthotomicus erosus (Wollaston), is a nonnative species that was first detected in North America in 2004. The dispersal characteristics of this insect are not known, but they are needed to accurately predict how quickly populations might spread. To estimate its intrinsic dispersal capacity, three mark-recapture trials were conducted in the Tulare Lake area near Kettleman City, California (Kings Co.), a homogenous agricultural landscape with no hosts and very few trees or shrubs. About 6000 marked beetles were released for each trial. Traps were placed in pairs with one trap baited with a commercially available bait for O. erosus, and the other baited with an improved pheromone bait. Pairs of traps were placed in the cardinal directions at 0.1, 0.5, 1, 2, 4, 6, 8, and 10 km radii. Preliminary assessment of the results suggests that O. erosus was captured primarily in the southern and eastern traps, reflecting the prevailing winds from the northwest. Recapture rates were approximately 10%. Most recaptured beetles were trapped at distances 100 and 500 m from the release point, and these moved to these locations within 20 to 60 minutes of release. A few individuals were recaptured between 4 and 10 km from the release point. There was no evidence of a wild population of O. erosus at this site. In a companion survival study of unreleased, marked beetles in cages, about 85% died after 48 hrs of outdoor exposure in the windy, hot, and dry weather of California Central Valley.
Species 1: Coleoptera Curculionidae
Orthotomicus erosus (Mediterranean pine engraver)