2-May-2011 Gilhouley Road, Hood River, Oregon

Site location

A most amazing sight awaits visitors to the small city of Hood River, Oregon.  Looking north, one sees the gleaming, rounded cap of Mount Adams.  Looking south, one sees the pointy peak of Mount Hood.  For a former flatlander like me, to be bookended by two snow-capped stratovolcanoes like that is a wonder.

A slightly more diminutive wonder awaits those in Hood River who look down: pine cone spiders.  This field day was my first and so far only time tapping ponderosa pine (Pinus ponderosa) cones in Oregon, but it was enough to put the state on the World Map of Pine Cone Spiders.

Sample site

Cones in clearcut amid Garry oak leaves

The sample site was a working forest of ponderosa pine and Douglas-fir (Pseudotsuga menziezii) containing scattered, shrub-sized Garry oaks (Quercus garryana).  I tapped ponderosa cones that had accumulated along the roadside as well as cones I found lying in an old clearcut.

Roadside cones illuminated by late
afternoon sun

Ebo evansae tapped from a cone

Tapping 99 ponderosa cones I collected 10 spiders from 3 species.  We were excited to find that one of these was a female Ebo evansae (Thomidisae), a species of crab spider with only one record in the Burke Museum's spider database.  But that is a database of Washington spiders.  Perhaps the species is more common in Oregon, where it has been documented in the northeastern part of the state.

Hungry ticks waiting to snag a blood meal from passing deer or a spider collector.

28-Apr-2011 Ginkgo Petrified Forest, Washington

Site location (click to enlarge)

Ginkgo Petrified Forest is located at the intersection of Interstate 90 and the Columbia River in Vantage, Washington, in a mostly treeless region of the state.  The nearest naturally-occurring ponderosa pines (Pinus ponderosa) grow about 35 miles to the west in the foothills of the Cascade Range.  Yet a lone ponderosa pine, perhaps planted for shade, stands in front of the Ginkgo Petrified Forest's ranger station, dropping cones onto the Oregon grape (Mahonia aquifolium), pine needles and rocks below.

Pine cone beneath Oregon grape
in full flower

Lots of old webs on these cones

Tapping 50 of those cones netted (pun intended) me only two spiders, a male and a juvenile Sitticus dorsatus (Salticidae).  This species of jumping spider is uncommon in Washington state - there were only five records in the Burke Museum's spider database previous to this one.  Too bad then that a third specimen I tapped from a cone got away! Despite the low specimen count in this sample, the frequency with which I found old webs on the cones indicated lots of past spider activity.

Showy phlox (Phlox speciosa) growing through tall sagebrush (Artemisia tridentata)

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.

24-Apr-2011 Nason Creek Rest Area & Southwest Leavenworth, Washington

Site locations (click to enlarge)

Marie Rose and I decided to take a mini vacation to see some of the giant landforms in eastern Washington created by the repeated, cataclysmic releases of water from Glacial Lake Missoula about 13,000 years ago.  Naturally, I brought my spider net.

Nason Creek R.A. sample site

Crossing the Cascade crest at Stevens Pass, we quickly descended into ponderosa pine (Pinus ponderosa) country and made a pit stop at Nason Creek Rest Area.  Rod Crawford and I had stopped there the previous summer, so I already knew that it was a convenient place to get a cone sample.  Tapping 71 cones, I collected 6 juvenile spiders.  The "pine cone spider" Euryopis formosa (Theridiidae) was the only identifiable specimen among them.

View of Leavenworth site from above

Me and some cones

Our next stop, the intersection of Route 2 and Icicle Creek Road in Leavenworth, was only a 20 minute drive down the mountain from Nason Creek Rest Area, but 1,000 feet lower in elevation.

Climbing up a small rocky prominence, I was able to find 31 ponderosa cones that hadn't rolled down off the mountain.  Luckily we didn't either!  Though small, this batch of cones was much more productive than the Nason Creek R.A. sample: 11 spiders and 4 species!  Only after several more years of sampling would we realize that 3 of those species, E. formosa, Pholcophora americana (Pholcidae) and Meioneta fillmorana (Linyphiidae), are the first-, second-, and third-most common spider species found in fallen pine cones in eastern Washington.

12-Apr-2011 Washington State Horse Park, Cle Elum, Washington

Site location

Eager to get back into a ponderosa pine (Pinus ponderosa) forest, I drove east from Seattle over Snoqualmie Pass to Washington State Horse Park.  Located on the west side of Cle Elum, this 112-acre forest was dominated by ponderosa pine and dotted with Douglas-fir (Psuedotsuga menziesii).

Sample site

Old ponderosa cones

Although spring had yet to, well, spring forth, most of the snow had melted and exposed extensive accumulations of ponderosa cones and, here and there, Douglas-fir cones too.  Interestingly, the scales on most of the ponderosa cones were open only on the upper, exposed side, whereas all of the scales on many of the Douglas-fir cones were completely open.

Euryopis formosa cryptic
with cone debris

Rod had warned me that it was too early in the season to find much at this elevation (almost 2,000 feet), and he was right.  Tapping 103 ponderosa cones got me only 9 spiders.  But my efforts were not for nothing, since 3 species were identifiable.  These included Euryopis formosa (Theridiidae), a species we'd eventually come to term a true "pine cone spider" since fallen pine cones are, so far, the only reliable microhabitat in which it is found in Washington.

Douglas-fir cone with spider signs

I also tapped 100 Douglas-fir cones and got only 3 spiders, all juveniles.  Despite the high vacancy rate, I could tell that spiders had used these Douglas-fir cones fairly extensively, since they'd left behind numerous webs and refugia.  Deyrup & Deyrup (1978)* noted that "Douglas-fir cones, though occasionally inhabited by spiders, are poor habitats for large or mobile predators because the cones close tightly during wet weather, leaving only a minute space at the base of each scale."  However, their study was conducted in Seattle, known for its damp climate.  I wonder if Douglas-fir cones might provide a more lasting microhabitat for spiders in drier climates like found in Cle Elum and elsewhere on the eastern slope of the Cascade Range?

*Deyrup, M. & N. Deyrup (1978) Pupation of Hemerobius in Douglas-fir cones. Pan-Pacific Entomologist 54:143–146.

First hint of spring, the aptly-name spring-beauty (Claytonia sp.)

8-Apr-2011 Golden Gardens Park, Seattle, Washington

Site location

Since Rod was unavailable for a combined field trip, I did another round of solo cone tapping, this time in Seattle's Golden Gardens Park.  Most of the public activity in this park is on the beach, but I found what I was looking for inland on the forested bluff: fallen pine cones.

Sample site

Try as I might, I never was able to figure out whether the pines here were introduced eastern white pines (Pinus strobus), like those I found in Green Lake Park, or the local native species western white pine (P. monticola).  Both are remarkably similar in appearance, and even the city forester was unable to confirm for me which species made up this stand in Golden Gardens Park.  Since the cones of the two species greatly overlap in size, perhaps the distinction is an academic one and is irrelevant to the spiders using them.

Native understory snuffed out by
invasive English ivy

Cone swallowed in ivy

What I do know for sure is that the entire forest was blanketed with layer upon layer of invasive English ivy (Hedera helix).  The ivy had thoroughly decimated the native forest undergrowth.  The stuff was so thick that my feet "sank" out of view.  Likewise, many cones were fairly well nestled within the ivy's matrix.

Tapping 76 cones I collected 55 spiders and 8 species.  As at Green Lake Park a few weeks before, 3 of these species were introduced: Lepthyphantes tenuis (Linyphiidae), Philodromus dispar (Philodromidae) and Theridion bimaculatum (Theridiidae).  Philodromus dispar was the most numerous identifiable species present (9 individuals), while the native Theridion sexpunctatum (Theridiidae) came in a close second (8 individuals).

A Cryphoeca exlineae in web

Another C. exlineae in web

At the time I was collecting, however, my attention and camera were drawn to individuals of the native agelenid Cryphoeca exlineae because they were conspicuous in their webs.  The concave upper side of P. strobus and P. monticola cone scales is apparently a good place to build such structures.

25-Mar-2011 Green Lake Park, Seattle, Washington

Site location

2011 was the year I began intensively sampling pine cone spiders in Washington state -- 42 sites by the end of the year!  Before 2011, I'd tap cones if there happened to be any at the sites I was assisting Rod Crawford in sampling.  But starting in 2011, Rod agreed to locate our sampling sites in places where ponderosa pine (Pinus ponderosa) was thought to occur.  This way I could tap cones more consistently.

Tennis court & pine cones

Our first sampling location of the year, Pilchuck Tree Farm, reportedly contained ponderosas, but we were unable to find any.  A few days later, though, I found a small grove of eastern white pines (Pinus strobus) on the west side of Seattle's Green Lake Park and tapped 32 spiders from 85 fallen cones.  The 2011 pine cone spider sampling season had begun!

Pinus strobus cone

If finding introduced species had been my goal, I couldn't have collected in a better spot.  Three of the 4 identifiable spider species I collected were introduced, as was the species of pine I collected them from!

Known distribution of Theridion tinctum.
Adapted from a
British Arachnological Society map

Presumably the P. strobus trees had been deliberately planted in the park (one had an identifying plaque on it), but the Theridion tinctum (Theridiidae), Ozyptila praticola (Thomisidae), and Philodromus dispar (Philodromidae) spiders I tapped from the cones were probably the descendants of passive stowaways on transatlantic ships that had docked in Seattle or Vancouver, British Columbia.

Stay tuned for reports of the 41 other pine cone spider collecting events from 2011!