Dendroctonus brevicomis Western pine beetles "swimming"
in oleoresin exuding from a pitch tube on the bark of ponderosa pine. The
beetle (in center of picture) and its mate underneath were observed
to burrow down through the viscous liquid into the entrance of the
gallery (directly under and to right of beetles) for up to several
minutes before returning and shoving out more resin. The resin is slightly toxic
and may exhaust the beetles; it also may eventually crystallize to
image (C) 1995 by John A. Byers