Wednesday, June 22, 2011

Alvord Basin Weekend, 17–19 June 2011

I spent last weekend (17–19 June) in the Alvord Basin of southeastern Oregon to check out the odonate action with several friends. This is a stunning area of wide-open high desert vistas below the humbling east face of Steens Mountain and it’s a special area for odonates. Several species reach their northern or northwestern limit at wetlands associated with hot springs in this area. In particular we visited Mickey Hot Springs, Alvord Hot Spring, Borax Lake, and Twin Springs, but only Mickey Hot Springs had any appreciable activity. At most of these hot springs, the water is too hot to support insect life where it leaves the ground, so follow the little streams to wetlands where the water has cooled sufficiently.




The "top" pool at Mickey Hot Springs. Sometimes you see odonates ovipositing here, but I'm sure it's too
hot for eggs/nymphs to survive.


Boiling water is leaving the ground further downslope—way too hot!

Just right! Eventually water drains into this well-vegetated wetland. By the time it gets here, the water has
cooled enough to support all sorts of life.



Within Oregon, the Alvord Basin is the only area where Bleached Skimmer (Libellula composita), Comanche Skimmer (L. comanche), and Red Rock Skimmer (Paltothemis lineatipes) are known, and Oregon’s first Desert Forktail (Ischnura barberi) was found here just last year. Some other “specialties” of desert wetlands in Oregon’s corner of the Great Basin include Hoary Skimmer (L. nodisticta), Desert Whitetail (Plathemis subornata), Paiute Dancer (Argia alberta), and Black-fronted Forktail (I. denticollis).

It’s been a very cool, wet spring all over the Pacific Northwest and it is just as evident—if not more so, in this normally arid basin where the average annual precipitation is about eight inches. All of the seasonally wet lakes and streams that are typically dry this time of year (or entirely dry some years) are full of water. The Alvord Desert—a dry lake bed of about 80 square miles was full of water right up to the brim. I’ve never seen that before. Steens Mountain was especially impressive for this time of year with lots of snow still clinging to its craggy eastern face (photo above).

The odonate activity was certainly anemic for this time of year. There were quite a few damselflies out, but not many dragonflies. Of the “specialties”, we saw only a few Bleached Skimmers, a couple Hoary Skimmers, and several Desert Whitetails. The widespread Western Pondhawk (Erythemis collocata) was fairly numerous and there were several Variegated Meadowhawks (Sympetrum corruptum), but we saw only a couple of darners (likely California Darner, Rhionaeschna californica) cruising the wetlands. Paiute Dancer, Black-fronted Forktail, and Western Red Damsel (Amphiagrion abbreviatum) were out in good numbers and there were scattered Western Forktail (I. perparva) and Pacific Forktail (I. cervula). We did not see a single bluet (Enallagma), however, which seemed very strange.

Below are a few odonates photographed at Mickey Hot Springs.

A male Paiute Dancer (Argia alberta).

A male Black-fronted Forktail (Ischnura denticollis).

An immature male Bleached Skimmer (Libellula composita). With maturity, the abdomen and thorax
will be covered with pale bluish-gray pruinescence and the eyes will turn pearly gray.


A male Desert Whitetail (Plathemis subornata)—again an immature. As he matures, the abdomen will
become covered with white pruinescence and the two zig-zaggy dark bands on each wing will coalesce
into a singe wide band.

Another Desert Whitetail, but a female this time.

In another week or two, there ought to be a lot more more dragonflies including additional species. It’s worth the trip!

3 comments:

  1. Awesome photos, Jim! I am inspired to get out there. Maybe I'll go next weekend!

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  2. @Ivan Phillipsen Ivan, the Alvord Basin is a really cool area for lots of reasons. Yes, you have to go!

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  3. Well, I went and it was awesome! Thanks for the inspiration. I put up a blog post about Mickey Hot Springs today. Cheers!

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