Wednesday, August 24, 2016

23-Aug-2016 Carnation, Washington

Site location map.  Click to enlarge.
Key: Blue - Ozyptila praticola confirmed, Yellow - O. praticola suspected,
Red - No O. praticola found
Yesterday I returned to my search for the introduced crab spider Ozyptila praticola (Thomisidae).  Since I've already found it in two places in the Snoqualmie River valley (Snoqualmie and Duvall), I wanted to continue my search into the foothills of the Cascades mountains east of the river valley.

Maybe not the best place to collect spiders...
My focal point was the Tolt Reservoir.  On a mountain biking website I had found a detailed description of a circular route to near that point which started in Tokul and ended near Duvall.  What a windfall!  Or so it seemed until I tried driving it.  Not too far beyond Tokul, the roads were gated and posted with warning signs about written permission being required before entering.  This approach being unavailable, I decided to try driving the final segment of the route "backwards" from Duvall.  Whether that approach is open to the public I still don't know, since road names on the signs and in the instructions didn't always match up, and I didn't have all the maps with me that I thought I had.  It was one of those days...  I'll have to return another time better prepared.

Cone source, a lone pine
A fallen cone
But the day wasn't a total loss since I was able to find cones to tap in Carnation and confirm that O. praticola is present at the midpoint of the Snoqualmie River valley.  The cone source was a black pine (Pinus nigra) growing on a street corner in the business district.  Its fallen cones were on a bed of pine needles through which sparse herbs were growing.  Tapping 50 cones I collected 18 spiders, 10 of them O. praticola.  Other spiders present in these cones included a Diplostyla (Linyphiidae) female and penultmiate male, a pair of mature Tenuiphantes tenuis (Linyphiidae) and two juvenile Clubiona (Clubionidae).  The cones also contained 25 harvestmen and a number of tiny snails.

A wall of corn marks the edge of town in Carnation

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