. The Canadian field-naturalist. Natural history; Sciences naturelles. 346 The Canadian Field-Naturalist Vol. 119 the temporal data, the translocation of EGS by humans also explains the discontiguous pattern of expansion. The surveys revealed that residents and pest control companies translocated live EGS, often beyond a "bar- rier" such as a river or mountain in the hopes that nuisance EGS would not return (Pynn 1999*). By 2004, EGS occurred throughout the Lower Mainland (Figure 3) and the Victoria region (Figure 4). The habitat selection analysis revealed that EGS did not use the l
. The Canadian field-naturalist. Natural history; Sciences naturelles. 346 The Canadian Field-Naturalist Vol. 119 the temporal data, the translocation of EGS by humans also explains the discontiguous pattern of expansion. The surveys revealed that residents and pest control companies translocated live EGS, often beyond a "bar- rier" such as a river or mountain in the hopes that nuisance EGS would not return (Pynn 1999*). By 2004, EGS occurred throughout the Lower Mainland (Figure 3) and the Victoria region (Figure 4). The habitat selection analysis revealed that EGS did not use the land types in proportion to their prevalence (X2 « , df = 5). EGS were found predominantly in the land type when the proportion of EGS is signif- icantly above the proportion of the land type's avail- ability (Figures 5 and 6). EGS in the Lower Mainland were found predominantly in Residential land types and not in Agricultural or Open land types (Figure 5). EGS in the Victoria region were also found predomi- nately in Residential land types and not in Agricul- tural, Open, or Parks land types (Figure 6). Discussion EGS have spread predominantly toward Residential areas. In the Lower Mainland, the Pacific Ocean to the west and conifer forest and mountains to the north have acted as barriers to their spread. Suitable habi- tat, specifically residential development, is available south and east and spread has proceeded further and more quickly in these directions. A similar pattern was seen in the Victoria region where EGS spread through- out the eastern peninsula of Vancouver Island, toward residential areas rather than west and north into areas dominated by conifer forests. The results suggest that EGS may continue to invade British Columbia, but are more likely to do so in residential areas and are un- likely to spread in areas still dominated by conifer forests. The land type categories were very general, however, because of the size of the region. I used the most detailed
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