25-Nov-2017 Laurelhurst Neighborhood, Seattle, Washington

Site location map. Click to enlarge.

Seattle has about 150 public shoreline access points, called "shoreline street ends", where public roads end at a body of water (map). During a visit to one such street-end mini park in the Laurelhurst neighborhood this summer, I noticed an eastern white pine tree (Pinus strobus) nearby that had dropped numerous open cones. A short break in the rain this day gave me just enough time to go back and tap those cones.

Source tree, an eastern white pine

Fallen cone microhabitat

The tree turned out to have dropped hundreds of open cones, most laying on a thick bed of pine needles undisturbed by groundskeepers. What a gold mine! Since so many cones were available, I tapped a super-sized set of 150 (50 is my standard) and collected 22 spiders.

The sample contained quite a variety of theridiids, including Cryptachaea, Enoplognatha, and Theridion, as well as the linyphiids Erigone, Lepthyphantes, Tachygyna, and Tenuiphantes. The most numerous spider present was Ozyptila probably-praticola (Thomisidae), of which I collected four juveniles.

A newly-planted future grove of redwood trees (Sequoia sempervirens) in
nearby Laurelhurst Park.