Chris Hill wrote:
>To add my two bits - a weekend trip to Fisher Creek in North Cascades
>National Park to collect aquatic insects (fully permitted by NCNP!)
>produced no dragonflies at all, neither larvae nor flying. There was
>habitat that I would consider prime for larvae, i.e., shallow warmish
>pools with submerged grass and abundant mosquito larvae to eat. But no
>odonates. So either we missed them, or the elevation (about 5,600 feet)
>precludes dragonflies. Incidentally, I was just a pack animal, assisting
>my wife who is doing her thesis research on the bugs.

If it was a hot, sunny day, I would have expected at least some dragons
even at 5,600 feet. They are common and diverse (at least 16 spp.) at
Roger Lake, in the Okanogan Highlands, at slightly higher elevation, and at
some lakes at 5,800 ft. below Sunrise in Mt. Rainier NP. However, the
Okanogan is drier than the North Cascades and probably supports more
dragonflies (warmer summers really make a difference).

If you found no larvae, that probably means there aren't any there, as the
few species of dragonflies of high-elevation marshes are often quite
common, and it's easy to find their larvae. Shallow bog/lake combinations
are the best habitats for dragonflies up in the mountains. Streams lack
them entirely, but there is one species (Black Petaltail, Tanypteryx
hageni) the larvae of which live in burrows in hillside seeps in the
Cascades and Olympics. They come out and walk around at night and eat
spiders! The black-and-yellow two-inch-long adults are rather tame,
sometimes landing on a light shirt. This is an ancient relict species,
with other family members in Gondwanaland, Japan, and southeastern U.S. It
or something like it was flying around these parts long before some
dinosaurs happened to grow feathers and take to the air.

Dennis Paulson, Director phone 206-756-3798
Slater Museum of Natural History fax 206-756-3352
University of Puget Sound e-mail dpaulson at ups.edu
Tacoma, WA 98416