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| The Dragonflies
(Insecta: Odonata) of the Columbia Basin, British Columbia: Field Surveys, Collections Development and Public Education Dragonflies
of the CB Table of Contents
By the end of the 1999 season we had visited over 291 sites and had identified 4,466 dragonflies during the two-year project. RBCM collections made before the survey accounted for 75 different sites and 594 specimens; thus, in total there are 366 Columbia Basin sites and 5,060 specimens in the RBCM database. Distribution maps and collection data for all species are found in Appendix 4 and can also be reached through individual species accounts in the Systematic Review section. Fifty-seven species were known from the Columbia Basin in British Columbia before the start of the project: at the completion, sixty-six species were on the list. The nine additions were: Calopteryx
aequabilis (River Jewelwing),
The inventory has also improved our understanding of the status of other species rarely recorded in the Columbia Basin. Thirteen of the inventoried species are considered rare, based on collections in museums. However, with increased study, species such as Aeshna tuberculifera (Black-tipped Darner), Somatochlora cingulata (Lake Emerald) and Gomphus graslinellus (Pronghorn Clubtail) will prove to be more widespread than initial records suggested. Others, such as Argia vivida (Vivid Dancer), live in restricted habitats that are threatened by human-caused development, and are more likely to be at risk, even if more populations are discovered. Several species, including Enallagma clausum (Alkali Bluet), E. hageni (Hagen's Bluet), Aeshna septentrionalis (Azure Darner) and Somatochlora hudsonica (Hudsonian Emerald), remain to be found in the region, but probably occur there. Calopteryx aequabilis (River Jewelwing), Lestes forcipatus (Sweetflag Spreadwing) and Somatochlora forcipata (Forcipate Emerald) are species new to British Columbia. C. aequabilis represents a new family of Odonata for B.C.: the Calopterygidae. This spectacular damselfly is recorded from Stevens County, Washington; and for several decades we had suspected that it lived in the streams of the Boundary district. However, we had not managed to find it there until July 1999, when Leah Ramsay discovered it near Christina Lake. In 1998, in a wetland near Donald in the Rocky Mountain Trench, Ramsay also found Lestes forcipatus, not confirmed elsewhere in Canada west of Saskatchewan. This is a good example of an uncommon species that had been overlooked simply because it was not expected, and because it very closely resembles the widespread Lestes disjunctus (Common Spreadwing). The species was subsequently discovered in 15 more sites in the region. Finding Somatochlora forcipata (Forcipate Emerald) was also a goal that had eluded us for years. This species had been collected about 3 kilometres from the British Columbia/Alberta boundary in Banff National Park in the 1920s (Walker and Corbet 1975). This ancient collection had remained the only record west of Manitoba. Surely it also had to live in "small spring runs" following "devious courses" (as described by Edmund Walker, the 1920s collector) west of the Continental Divide. After much searching, S. forcipata was located at three peatland sites in Yoho and Kootenay national parks. It is clearly a sparsely distributed member of the Rocky Mountain dragonfly community, and an inhabitant of an apparently rare habitat as well. The 66 species now known from the Columbia Basin represent 77% of the 86 species recorded from British Columbia, and 33 % of the 202 recorded in Canada. At least six more species are thought to occur in the region, and several more than that will probably be added to the list. All these species are native to Canada. Thirteen species in the Columbia Basin are considered rare or potentially at risk (Appendix 1).
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