title: Cold Tolerance of Halyomorpha halys (Hemiptera: Pentatomidae) Across Geographic and Temporal Scales.
abstract: The brown marmorated stink bug, Halyomorpha halys (Stål), is native to eastern Asia and is presently invading North America. Little is known about the exposure to and effects of winter temperatures in newly invaded regions on H. halys The overwintering habitats that this species utilizes vary greatly in their thermal buffering capacity. They naturally overwinter in aggregations beneath loose bark on trees and in cliff outcroppings, but will also commonly aggregate in buildings. Effects of cold temperatures such as mortality and freezing have yet to be quantified in the invading population. We report that H. halys is chill intolerant (i.e., dies before reaching its freezing point), and that the degree of cold tolerance of populations in North America differs by season, sex, and acclimation location. The mean winter supercooling point (± SEM) of individuals acclimated in Minnesota was -17.06 °C ± 0.13 and in Virginia was -13.90 °C ± 0.09. By using laboratory assays of lower lethal temperatures and ambient air temperature records, we accurately forecasted mortality for field experiments in Minnesota and Virginia. Temperature refugia provided by human-built structures are likely crucial for overwintering survival during atypically cold winters and possibly contribute to the northern geographic range expansion of this economically damaging insect in the temperate climates of North America.
authors.affiliation: Department of Entomology, University of Minnesota, 219 Hodson Hall 1980 Folwell Ave., St. Paul, MN 55108 (cirax002@umn.edu; hutch002@umn.edu), cirax002@umn.edu.
authors.forename: Theresa M
authors.initials: TM
authors.lastname: Cira
authors.affiliation: Northern Research Station, Forest Service, United States Department of Agriculture, 1992 Folwell Ave., St. Paul, MN 55108 (rvenette@fs.fed.us), and.
authors.forename: Robert C
authors.initials: RC
authors.lastname: Venette
authors.affiliation: Department of Entomology, Virginia Tech, 170 Drillfield Dr., Blacksburg, VA 2406 (daigner@vt.edu; tkuhar@vt.edu; mullinsd@vt.edu; sgabbert@vt.edu).
authors.forename: John
authors.initials: J
authors.lastname: Aigner
authors.affiliation: Department of Entomology, Virginia Tech, 170 Drillfield Dr., Blacksburg, VA 2406 (daigner@vt.edu; tkuhar@vt.edu; mullinsd@vt.edu; sgabbert@vt.edu).
authors.forename: Thomas
authors.initials: T
authors.lastname: Kuhar
authors.affiliation: Department of Entomology, Virginia Tech, 170 Drillfield Dr., Blacksburg, VA 2406 (daigner@vt.edu; tkuhar@vt.edu; mullinsd@vt.edu; sgabbert@vt.edu).
authors.forename: Donald E
authors.initials: DE
authors.lastname: Mullins
authors.affiliation: Department of Entomology, Virginia Tech, 170 Drillfield Dr., Blacksburg, VA 2406 (daigner@vt.edu; tkuhar@vt.edu; mullinsd@vt.edu; sgabbert@vt.edu).
authors.forename: Sandra E
authors.initials: SE
authors.lastname: Gabbert
authors.affiliation: Department of Entomology, University of Minnesota, 219 Hodson Hall 1980 Folwell Ave., St. Paul, MN 55108 (cirax002@umn.edu; hutch002@umn.edu).
authors.forename: W D
authors.initials: WD
authors.lastname: Hutchison
mesh_terms: D000064:Acclimatization; D000818:Animals; D003080:Cold Temperature; D005260:Female; D020062:Heteroptera / Q000254:growth & development / Q000502:physiology*; D058865:Introduced Species; D008297:Male; D008910:Minnesota; D009758:Nymph / Q000254:growth & development / Q000502:physiology; D012621:Seasons; D014768:Virginia
keywords: chill intolerance; cold hardiness; invasive species; supercooling point