title: Nonlethal Effects of Nematode Infection on Sirex noctilio and Sirex nigricornis (Hymenoptera: Siricidae).
abstract: A nonnative woodwasp, Sirex noctilio F., has established in pine forests in eastern North America. To facilitate prediction of the full range of impacts S. noctilio could have as it continues to spread in North American forest ecosystems, we studied the effects of infection by a nonsterilizing parasitic nematode on S. noctilio size, fecundity, and flight capacity and on the native woodwasp, S. nigricornis, size and fecundity. We also developed predictive models relating size to fecundity for both species. On average, S. noctilio (3.18 ± 0.05 mm) were larger than S. nigricornis (2.19 ± 0.04 mm). For wasps of similar size, S. nigricornis was more fecund. Nematode infection negatively affected potential fecundity by a mean difference of 36 and 49 eggs in S. noctilio and S. nigricornis, respectively. Nematode-infected males of S. noctilio, however, were larger than uninfected individuals. Nematode infection showed inconsistent results on mean speed and total distance flown by S. noctilio males and females. Nematode infection did not affect total distance flown by females, and so is unlikley to have a direct, or strong influence on S. noctilio flight capacity. Models developed to predict fecundity of Sirex spp. from body size, based on the close relationship between pronotum width and potential fecundity for both species (R(2) ≥ 0.69), had low measures of error when compared with true values of fecundity (± 25-26 eggs).
authors.affiliation: Natural Resources Canada Canadian Forest Service, Great Lakes Forestry Centre, 1219 Queen St. E, Sault Ste. Marie, ON, P6A 2E5, Canada (ljhaavik@gmail.com; jeremy.allison@nrcan-rncan.gc.ca; christian.macquarrie@nrcan-rncan.gc.ca; reg.nott@nrcan-rncan.gc.ca; jean.turgeon@nrcan-rncan.gc.ca), Corresponding author, e-mail: ljhaavik@gmail.com.
authors.forename: Laurel J
authors.initials: LJ
authors.lastname: Haavik
authors.affiliation: Natural Resources Canada Canadian Forest Service, Great Lakes Forestry Centre, 1219 Queen St. E, Sault Ste. Marie, ON, P6A 2E5, Canada (ljhaavik@gmail.com; jeremy.allison@nrcan-rncan.gc.ca; christian.macquarrie@nrcan-rncan.gc.ca; reg.nott@nrcan-rncan.gc.ca; jean.turgeon@nrcan-rncan.gc.ca).
authors.forename: Jeremy D
authors.initials: JD
authors.lastname: Allison
authors.affiliation: Natural Resources Canada Canadian Forest Service, Great Lakes Forestry Centre, 1219 Queen St. E, Sault Ste. Marie, ON, P6A 2E5, Canada (ljhaavik@gmail.com; jeremy.allison@nrcan-rncan.gc.ca; christian.macquarrie@nrcan-rncan.gc.ca; reg.nott@nrcan-rncan.gc.ca; jean.turgeon@nrcan-rncan.gc.ca).
authors.forename: Chris J K
authors.initials: CJ
authors.lastname: MacQuarrie
authors.affiliation: Natural Resources Canada Canadian Forest Service, Great Lakes Forestry Centre, 1219 Queen St. E, Sault Ste. Marie, ON, P6A 2E5, Canada (ljhaavik@gmail.com; jeremy.allison@nrcan-rncan.gc.ca; christian.macquarrie@nrcan-rncan.gc.ca; reg.nott@nrcan-rncan.gc.ca; jean.turgeon@nrcan-rncan.gc.ca).
authors.forename: Reginald W
authors.initials: RW
authors.lastname: Nott
authors.affiliation: Faculty of Forestry, University of Toronto, 33 Willcocks St., Toronto, ON, M5S 3B3, Canada (kathleen.ryan@silvecon.com).
authors.forename: Kathleen
authors.initials: K
authors.lastname: Ryan
authors.affiliation: Natural Resources Canada Canadian Forest Service, Great Lakes Forestry Centre, 1219 Queen St. E, Sault Ste. Marie, ON, P6A 2E5, Canada (ljhaavik@gmail.com; jeremy.allison@nrcan-rncan.gc.ca; christian.macquarrie@nrcan-rncan.gc.ca; reg.nott@nrcan-rncan.gc.ca; jean.turgeon@nrcan-rncan.gc.ca).
authors.forename: Peter
authors.initials: P
authors.lastname: de Groot
authors.affiliation: Natural Resources Canada Canadian Forest Service, Great Lakes Forestry Centre, 1219 Queen St. E, Sault Ste. Marie, ON, P6A 2E5, Canada (ljhaavik@gmail.com; jeremy.allison@nrcan-rncan.gc.ca; christian.macquarrie@nrcan-rncan.gc.ca; reg.nott@nrcan-rncan.gc.ca; jean.turgeon@nrcan-rncan.gc.ca).
authors.forename: Jean J
authors.initials: JJ
authors.lastname: Turgeon
mesh_terms: D000818:Animals; D049628:Body Size; D005260:Female; D005298:Fertility; D005426:Flight, Animal; D058865:Introduced Species; D008297:Male; D009864:Ontario; D010572:Pest Control, Biological; D013045:Species Specificity; D014431:Tylenchoidea / Q000502:physiology*; D014863:Wasps / Q000469:parasitology* / Q000502:physiology*
keywords: Deladenus spp.; dispersal; flight mill; size–fecundity relationship; woodwasp