Saturday, October 17, 2015

14-Oct-2015 Everett, Tulalip, and Marysville, Washington

Site location map. Click to enlarge
I continued my search for the introduced crab spider Ozyptila praticola (Thomisidae) by traveling north along the I-5 urban corridor.  I stopped first in south Everett, then crossed the Snohomish River and sampled in Tulalip and Marysville.


Everett site, P. sylvestris in center.
Having found that commercial areas are among the easiest places to find accessible fallen cones, I cruised the Everett Mall area and quickly found a fencerow of conifers that included Scots pine (Pinus sylvestris). 

P. sylvestris cones are tiny
The day was still cloudy and cold when I began collecting.  I enjoyed listening to the chirping of a Pacific tree frog (Pseudacris regilla) while I loaded my net with 50 cones, then retreated to the warm car to tap them.  From those cones I collected 10 spiders and 3 species.  As with my previous sample from Shoreline, the most common species present were O. praticola (another mark on the WA distribution map!) and Tachygyna vancouverana (Linyphiidae).

Snail & friends
Among the non-spider inhabitants of these cones was this diminutive snail, less than 5 mm in diameter.  It immediately began exploring my net while some even tinier creatures began to explore it.

Can you spot the female O. praticola?
Speaking of tiny things, plenty of the spiders that I collect grow to a maximum of 1-2 mm in length.  Adult O. praticola are larger than that (3-4 mm long), but have the habit of curling up and 'playing dead' when in the net.  Unless they start to move about, it takes some skill to distinguish them from the brown bits of detritus in the net.  Fortunately they have a recognizable silhouette, which helps.  I've circled an adult female in orange in the photo to the right.


Tulalip site
P. monticola cones in Tulalip
Having found the cones so quickly in Everett, I had plenty of time left to proceed north to Tulalip and neighboring Marysville for further sampling.  In Tulalip I was once again able to very quickly find fallen pine cones.  Cones beneath an eastern white pine (Pinus monticola) growing next to a McDonald's had miraculously escaped the chopping blades of lawn mowers.

Grammonota kincaidi females
I tapped 50 of these cones and collected 10 spiders and 2 species.  The most common spider looked like Grammonota kincaidi, a linyphiid found on conifer foliage in western Washington.  No O. praticola, though, so I crossed under I-5 and into Marysville to look for another collection site.


P. nigra cones in Marysville
Marysville site
Marysville really knows how to welcome pine cone spider collectors!  Greeting visitors entering the city from northbound I-5 is a mini park with the city's sign and a small grove of black pines (Pinus nigra).  And, unlike many of my recent experiences with P. nigra cones south of Marysville, the scales of the fallen P. nigra cones here were open.  From 50 tapped cones I collected 7 spiders and 2 species of linyphiid microspiders.  But the most numerous denizens of these cones were juvenile Enoplognatha, probably ovata (Theridiidae).  I've tapped them from every set of cones I've sampled this year in the Puget Sound area of Washington.

I found no O. praticola in Marysville.  At present, then, the northern-most known location of Ozyptila praticola in Washington state is the 9800 block of 3rd Ave SE in Everett.

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