Tweeters,

I forgot to mention that due to some combination of water levels, weather, and previous abundance, two species of Odonata are more common in the Malheur basin than anyone has ever seen before, and it is a real phenomenon. The people who live there have never seen anything quite like this.

Striped Meadowhawk (Sympetrum pallipes) is a small dragonfly with red males and yellow-brown females. There must be millions of them in the basin, as everywhere we stopped they were superabundant. They were especially notable at oases such as Frenchglen, P Ranch, and the refuge HQ, but they really were everywhere. They were flying southeast into a light breeze by the hundreds on several occasions, once single dragonflies and - around midday yesterday just east of Hines - as copulating pairs. They passed us at 10-20/minute within close vision, a flight more like a migratory flight than a local dispersal, yet the species is not known to be migratory, so I don't know what was going on. It was a never-before-observed phenomenon.

Spotted Spreadwing (Lestes congener) is a rather large, dull damselfly in which the wings are held out from the body, not over it as in most damselflies. These too were superabundant, in some places astonishingly so. At the refuge HQ, they flew up from the grass almost in clouds, and they were arrayed all along the sunny sides of tree trunks up to the canopy level in the cool early morning.

Both of these species breed in seasonal wetlands. They lay their eggs in dry places low enough that they fill with water during the winter. The eggs hatch in spring, the larvae develop, and the adults emerge in summer and begin the cycle again. For some reason, conditions last fall, winter, and spring were just perfect for a massive emergence of these species from that area. We saw them in numbers all the way west to the rest area 16 miles W of Burns, but not many beyond that. These all were sexually mature, although I never saw any of the spreadwings mating. I should add that both species are common throughout the PNW, but not usually in these numbers.

Other than a few Blue-eyed Darners (Rhionaeschna multicolor), we saw no other species of dragonflies or damselflies at all, which in itself was quite a surprise.

Anyone who goes there will see these critters, and I thought I would add a comment about them.

Dennis
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Dennis Paulson
1724 NE 98 St.
Seattle, WA 98115
206-528-1382
dennispaulson at comcast.net



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