Grylloblattids in managed forests of South-central British Columbia
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We collected 147 specimens of grylloblattids (Grylloblatta campodeiformis) in pitfall traps in subalpine spruce-fir forest and lower elevation cedar-hemlock forest at two study sites in south-central British Columbia, Canada. Grylloblattids are of conservation interest because of the high degree of endemism in western North America and because little is known of the ecology of these insects. Mature grylloblattid individuals were caught primarily in early spring or late fall, while immature individuals were caught in traps set under the snow in winter. Grylloblattids occurred in clearcuts, partial cuts and uncut forest at both sites. Year-round collections of grylloblattids from a variety of forest habitats have not previously been reported. However, the insects were rare at one study site in old clearcuts and had different seasonal patterns of captures in recent clearcuts with intensive site preparation compared to partially-cut or uncut areas. At a second study site, they showed an affinity for cutblock edges and small patch cut harvest treatments that produce abundant edge. No grylloblattids were collected during similar sampling at a third site in dry Douglas-fir (Pseudotsuga menziesii) forest. The unexpected abundance of grylloblattids at two sites suggests that they may be widespread in wetter forest sites, but dry forests with low snowfall may act as a geographic barrier. Grylloblattids appear to tolerate or benefit from forest harvesting, other than in large clearcuts with intensive site preparation.