RESULTS
1. Summary of Results 2000-2005
- Approximately 780 separate sites were visited at least
once.
- Approximately 10,340 adult and 1400 larval dragonflies (total
of 11,740) were collected and deposited in the Royal BC Museum. The amount of
new habitat-association information that can be gleaned from associating these
dragonfly records with the ecological data of sites is considerable. The
ensuing baseline information for long-term monitoring of ecosystem health is
also considerable. The risks to dragonfly populations and other organisms from
these collecting efforts is minimal. There are essentially no risks to
populations, even of rare species, from this sort of collecting. Specimens in
research collections have many values. For example, they serve as standards
for species identification and unequivocally document historical status,
distribution, and present geographical variation, including 'hidden', as yet
undescribed species. In addition, they contain life-history and ecological
information such as the habitat choice of species and the time of adult
emergence and breeding.
- 56 species were known in the region at the beginning of the
survey; 9 more species were discovered: Lestes forcipatus,
Amphiagrion abbreviatum,
Aeshna tuberculifera,
Rhionaeschna californica, Epitheca
spinigera, Somatochlora
brevicincta, S. forcipata,
Sympetrum corruptum and S. madidum. Two of these, Amphiagrion and Epitheca,
were not on the list of probable species at the start. Three species from the
original probable list still remain to be found in the study area. A total of
65 species is now known for the study area (north of latitude 52º) and at
least three additional species probably occur in the region. The total of 68
species represents 78% of the provincial fauna.
- One species, Somatochlora brevicincta, was the
only species recorded new to BC. This was a surprising discovery; previously
it was known from only a few locations in Quebec, Maine and the Atlantic
provinces. After its initial discovery on Bell Mountain near McBride in 2000,
we collected it at another nine locations, all along the western margin of the
Rocky Mountains.
- Between 2000 and 2003 the conservation status ranks of 15
species found in northern BC were changed. This is 17% of BC species; 14
species are now less at risk and one is considered more at risk. Of the 14
species considered of management concern at the beginning of the surveys in
2000, only nine were so designated as of December 2005. The changes to the
provincial Red and Blue lists as a result of this inventory mean that
conservation studies are more able to focus on species truly in need of
individual attention. Our knowledge of the distribution and status of northern
dragonfly taxa has been enhanced. As the region they inhabit is being altered
by human development, such improved understanding of the fauna will help in
their conservation. Locating viable populations will give agencies and
organizations concerned with conservation critical knowledge to enable them to
secure habitat through land designation, habitat enhancement, or stewardship
agreements with landowners. Once the true status and detailed distribution of
the rarer dragonflies is known, management guidelines can be drawn up.
Preliminary management information is a product of the project.
- Four types of colour distribution maps (including histograms
showing flight period) for each dragonfly species in BC were produced. These
348 maps (plus 3 summary maps) are a major product of this project.
- Public knowledge and appreciation will increase significantly
as a result of the information gathered by the inventory and distributed via
publications, presentations, and the RBCM's Living Landscapes Web
page.
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