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Photo#229936
Spider Cairn 3 - Rhysodromus alascensis
Copyright © 2008 Stephen Hart

Spider Cairn 3 - Rhysodromus alascensis
blue Mountain/Deer Park, Olympic National Park, Clallam County, Washington, USA
September 29, 2008
More spider cairns, as posted in the thumbnail below. In this case, it looks like egg shells, rather than spiderling exoskeletons inside.
This cairn includes, as part of the building material, an exuvia. It looks like it might be from a fire-colored beetle larva.
This spider was a few inches away:


Previous spider cairn photos:

Images of this individual: tag all
Spider Cairn 3 - Rhysodromus alascensis Spider Cairn 3 - Rhysodromus alascensis Spider Cairn 3 - Rhysodromus alascensis Spider Cairn 3 - Rhysodromus alascensis
Contributed by Stephen Hart on 29 September, 2008 - 10:07pm
Last updated 8 October, 2011 - 5:36pm

Reference and many images
I found a reference for the cairn-building behavior
“At least one species, Philodromus alascensis, places its egg sac in a small, rocky recess, where it is covered with grains of sand, wood flakes, and other debris.”

Field Guide to the Spiders of California and the Pacific Coast States
Text by R. J. Adams Illustrations by Tim D. Manolis”
University of California Press 2014

Rhysodromus alascensis on Olympic Natural History, 45 slides
… Stephen Hart, 9 June, 2018 - 6:45pm

Moved
Moved from Unidentified Spider Egg Sacs.
… Charley Eiseman, 8 October, 2011 - 5:36pm

Moved
Moved from Spiders.
… Charley Eiseman, 6 June, 2009 - 11:10pm

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