Tuesday, April 14, 2015

25-Apr-2011 Chelan Butte & Lake Chelan State Park, Washington

Sample sites (click to enlarge)
The summit of Chelan Butte offers towering views of the Columbia River to the south and east, and of Lake Chelan to the northwest.  It also offers a scattered grove of ponderosa pines (Pinus ponderosa) and a modest number of fallen cones.

Chelan Butte sample site
overlooking Columbia River
At this early season and high elevation (3,700 feet), however, those cones didn't offer much in the way of spiders: 3 juveniles and 1 species (Titanoeca nigrella, family Titanoecidae) from 38 tapped cones, or an average of only 0.08 spiders per cone. 

Lake Chelan State Park sampling site
About 2,500 feet below, however, I tapped 31 spiders and 8 species from 80 ponderosa cones outside Lake Chelan State Park (elevation 1,190 ft), an average of 0.4 spiders per cone! We had seen a similar elevational contrast the previous day at Nason Creek Rest Area & Southwest Leavenworth.  Besides spring being noticeably more advanced at the Lake Chelan State Park site, the vegetation there was also structurally more complex than on the summit of Chelan Butte.

A pearl of great price was hidden away in this cone: a spider's egg sac.

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