Tuesday, June 28, 2016

21-June-2016 From Gold Bar to Skykomish, Washington

Site location map. Click to enlarge.
On a previous trip to the Skykomish River valley in search of the introduced crab spider Ozyptila praticola, I found adult specimens in Monroe, none in Sultan or Startup, and then one juvenile in Gold Bar.  My plan this day was to continue my search "upstream" (southeastward) as far as the town of Skykomish.  My first stops were in Index and Baring, but much to my disappointment I was unable to find any accessible cones to tap in either community.  I had better luck in Grotto and Skykomish, and ended the day taking an additional sample in Gold Bar.


"Safety follows wisdom"
Grotto is a tiny community at the foot of Baring Mountain.  A "safety trophy" awarded to the Northwest Portland Cement Co. for a "perfect safety record in 1954" is the only clue to Grotto's dusty industrial past; it was a town constructed in 1927 by Portland Cement as the site of a cement plant that processed limestone quarried from the hillsides of the Lowe Creek valley, located across the Skykomish River. The plant was dismantled in 1967, but a small community remains.  Interestingly, all of the online historical information I found on Grotto had been assembled by model train enthusiasts!

Cone source trees in foreground
and background
My cone source was three mature Douglas-fir trees (Pseudotsuga menziesii) on a street corner.  Many of the cones were still damp from rain the previous night and had only partially opened scales.  Nonetheless, I was able to tap a total of 100 cones of reasonable quality from two separate accumulations.  In all those cones I only found 2 spiders, both female Tenuiphantes tenuis (Linyphiidae).

Some of the drier fallen cones in Grotto
Though the spider population in these fallen cones was disappointing, the human population in Grotto was a delight.  I enjoyed conversation with a woman from the Bay Area of California who was visiting her daughter, and a young mother whose yard was bordered by one of the cone-dropping trees.  Even a UPS delivery person stopped briefly to ask what I was collecting, and to find out more about a spider he's been seeing in his home in Monroe.  Grotto is definitely on my list of most welcoming places to search for spiders!


BNSF train rolling through Skykomish
My Skykomish cone source
By the time I got to Skykomish I was ready for lunch, so stopped by the Cascadia Inn's cafe.  As in Grotto, I enjoyed more friendly spider-centric conversation, this time with the waitress, while watching BNSF trains roll slowly by.  Quite enjoyable!

Erigone male's carapace edged in denticles
The good thing about small towns like this is it doesn't take long to search the area for cone deposits.  I quickly found more fallen Douglas-fir cones on a sidewalk near the post office.  The sidewalk was covered in tree needle litter, cones and herbs.  Clearly nobody had trod on it for years, much to my benefit.  I tapped 50 fallen cones and collected 3 mature spiders, all Erigone (Linyphiidae).

Gold Bar

Mystery spider from Gold Bar
Mystery spider from Gold Bar
Turning towards home, I decide to tap another set of cones in Gold Bar to see if I could replicate my earlier discovery of O. praticola there.  I returned to the grocery store parking lot where I'd found the single juvenile specimen earlier in the year, but tapped a different group of cones than before.  From 50 fallen Douglas-fir cones I collected 3 spiders and 2 species. One was Enoplognatha thoracica (Theridiidae), which I had tapped from cones in Gold Bar before.  The other was a mysterious female spider Rod Crawford dubbed "curious" after seeing photos.
UPDATE [3 July 2016]: The mystery spider is Zodarion rubidum (Zodariidae). Read more about the significance of that here.

The spider yield from fallen cones was uniformly very low on this field trip, perhaps a symptom of the advancing summer dry season.  The day after I took these samples, Rod went on a collecting trip in the hills above Index and found litter spiders to be sparse there as well. However, summer dryness doesn't drive O. praticola from fallen cones in some small plots that I monitor monthly in Seattle, so I doubt that was a factor in O. praticola's absence from samples this day either.  But that's just a guess.

A bridge over the South Fork of the Skykomish River. A sign reads "One car at a time",
for obvious reasons. Another sign advises drivers to "retract mirrors before crossing".

Saturday, June 18, 2016

12-June-2016 Gig Harbor, Washington

Sample sites. Click to enlarge.
I had intended on searching for the introduced salticids Pseudeuophrys lanigera and Sitticus pubescens on building exteriors and stone walls in Gig Harbor on the same day I sampled on Vashon Island, but I ran out of time.  Gig Harbor was of interest because P. lanigera has been found recently in Bremerton, so that raised the possibility of wider dispersal on the Kitsap Peninsula.  Additionally, having collected a male Ozyptila praticola on Vashon, I also wanted to see if I could find any on the coast of the Kitsap Peninsula across Colvos Passage from Vashon Island.  I've not found O. praticola in other places I've sampled on the peninsula, including nearby Square Lake, but those previous sample sites were more or less natural areas.  So far, O. praticola appears to be synanthropic in western Washington, so it made sense to do some city sampling, and Gig Harbor again fit the bill.


A fallen white pine cone
Downtown cone source
My first cone source was a towering western white pine (Pinus monticola) on Judson Street.  Dozens of fallen cones lay on a bed of pine and red-cedar litter, sometimes under rhododendrons and other shrubs.  I tapped 55 cones and collected a bounteous 32 spiders and 3 identifiable species.  They were all species I find in cones in the Seattle conurbation: Tenuiphantes tenuis, Cryptachaea blattea and Philodromus dispar.

Lots of attractive stonework

This site was only a block from the harbor area, so I enjoyed the scenery as I scanned building exteriors and stone and brick walls for jumping spiders.  I found several Salticus scenicus, but nothing else.

High School

Gig Harbor High School
Female Platycryptus californicus
on school atrium pillar
My next stop was the Gig Harbor High School.  The building is huge and with a complex footprint, providing me with another excellent opportunity to look for wall-loving salticids.  I again found S. scenicus as well as a gorgeous female Platycryptus californicus.

Gig Harbor H.S. fallen cones
This dary-eyed junco (Junco hyemalis)
was my only company
A fairly dense mixed stand of trees grows between the street and the school's front driveway, with a dense salal understory.  I tapped 50 fallen Douglas-fir (Pseudotsuga menziesii) cones there and collected only 1 spider, a juvenile from the family Amaurobiidae.

West Harbor Heights

West Harbor Heights sampling site
My final cone-tapping spot for the day was a small grove of Douglas-firs growing between two parking lots. I tapped 50 cones and collected only 6 spiders, all linyphiids.  Only one spider was identifiable to species, a female Tenuiphantes tenuis.

I didn't find any of the three species of introduced spiders I was looking for in Gig Harbor.  Of course it is impossible to prove that something isn't present, but I think it likely that if O. praticola were in the city, odds are good that I would have detected it after tapping 50 cones in three places.  I base this on how frequently I find at least one O. praticola individual in samples taken in its known range in the Seattle conurbation.  As for the salticids, I have no idea how adequate my intensity of searching was to detect them if they're present.  All I can conclude is that if they are indeed present, they don't appear to be numerous or widespread.
Pleasure boats moored in the harbor

9-June-2016 Liberty, Washington

Site location map. Click to enlarge.
With rain likely on the west side of the Cascades, Rod Crawford and I headed across Snoqualmie Pass to (hopefully) drier weather and my favorite microhabitat, ponderosa cones!

We centered our collecting around the former mining town of Liberty.  Our first site was Liberty Meadow, located just west of town.  From there we headed a few miles north up Lion Gulch into a lovely ponderosa pine (Pinus ponderosa) forest about 700 feet higher in elevation.

Liberty Meadow

Isolated ponderosas in Liberty Meadow
Lots of cones!
Liberty Meadow features a number of isolated ponderosas, so I decided to tap 50 cones dropped by one tree.  What I found in them was a surprise: almost every spider I tapped appeared to be of the same species, and one I didn't recognize. But they sure were beautiful.

Juvenile Steatoda, 1 of 14!
Oxyopes scalaris from pine foliage
I wondered whether this was a fluke, and so decided to tap another 50 cones that had fallen from a different isolated ponderosa.  The result was the same!  In all, I collected 18 spiders from 100 tapped cones, 14 of them being what turned out to be a Steatoda (Theridiidae).  Although the palps on many of them looked well-defined to the naked eye, they turned out to be penultimate males and so we couldn't identify the species.  Drat!
UPDATE (2 July 2016): We returned a few weeks later and collected mature specimens, identified as Steatoda washonaRead more about it here!

Rod had exhausted the habitats he was interested in by the time I was done tapping those 100 cones and beating the pine trees' foliage, so we drove on to our site up Lion Gulch.

Lion Gulch

Looking down at cone tapping site
(near car) from nearby hillside
Tiger lily (Lilium columbianum)
The lupines and lillies growing between the ponderosas on the gulch slopes were at their peak, a lovely sight.  We parked at a campsite just off the road and I began tapping a set of 50 ponderosa cones.

Fallen ponderosa cones in Lion Gulch
Female Gnaphosa muscorum w/egg
sac found under hillside rock
I collected 9 spiders from 5 families.  Three species were identifiable: the theridiids Dipoena lana and Euryopis formosa, and the gnaphosid Poecilochroa montana.  None of the Steatoda from the meadow, however.  This was only the second time I've tapped D. lana from cones, but P. montana is no stranger to them and of course I find E. formosa in cones at about half of eastern Washington sample sites.

You can read Rod's trip narrative here and view his photo album here!

Chipmunk licking the sandstone monolith on a nearby hilltop

Wednesday, June 8, 2016

6-June-2016 Vashon Island, Washington

Site location map. Click to enlarge.
In my search for the limits of Ozyptila praticola's range in Washington state, I've visited shopping mall parking lots, college campuses, suburban back yards and rural enclaves.  But this was my first visit to an island.  That getting there required a ferry ride on a beautifully sunny day made the destination all the more enticing.

Downtown Vashon

Eastern white pines
Fallen white pine cones
I already had my first destination planned before arriving on the island: two huge white pine trees in downtown Vashon that I'd spotted via Google Maps Street View.  The trees turned out to be eastern white pines (Pinus strobus), and hundreds of their fallen cones had accumulated on the pine needle litter around their bases.  It seemed the perfect spot to start the day's collecting with a bang, but the opposite turned out to be true.  I tapped 100 cones and collected only one juvenile Phrurotimpus sp. and one juvenile harvestman.  I did notice that these cones were quite dusty from road debris, so perhaps this affected their attractiveness to spiders?

Ober Park Park & Ride

Black and Scots pines
No shortage of black pine cones!
After that disappointing start, I retraced my steps to a Park & Ride lot that I had noticed on the way into town from the ferry.  The entrance was decorated with two black pines (P. nigra) and a Scots pine (P. sylvestris), and their fallen cones had been allowed to accumulate on the needle litter below.  I tapped 100 black pine cones and collected 31 spiders and 5 species.  Now that was more like it!  Perhaps not surprisingly, the mix of spiders was very much like what I've tapped from cones in the Seattle area: juvenile philodromids, Enoplognatha thoracica and E. probably-ovata, tons of Tenuiphantes tenuis (7 females!), one Tachygyna female and, yes, one male Ozyptila praticola.

While in Vashon I chanced upon a place called Hastings Cone Gallery.  Was it possible that someone else had an interest in confer cones, and had some on display?!  The place was closed so I pressed my nose against the glass in great anticipation, only to find what looked like a cafe.  A very nice-looking cafe to be sure, but not a pine cone in sight.  There was some lovely art on the walls, however.  I've since learned that the place is named for its owners, Megan Hastings and Adam Cone, who exhibit art in their cafe.  Too bad I didn't stop by during business hours, because maybe I could have at least found that special kind of edible "cone" that doesn't contain spiders (one would hope), the scone.

Paradise Ridge Equestrian Park

Double row of Douglas-firs
Nobody home but C. exlineae
Since I was eventually going to take the ferry from the southern terminal in Tahlequah, I decided to search for a final collecting site on that half of the island.  At Paradise Ridge Equestrian Park I found an inviting double row of Douglas-firs (Pseudotsuga menziesii) with plenty of cones and litter beneath them, reminiscent of my collecting site in Snoqualmie.  I tapped 75 cones but collected only 3 spiders, all female Cryphoeca exlineae.

Male Ozyptila praticola
Female Cryphoeca exlineae
Vashon Island is the western-most place in Washington state where I've found the European species O. praticola.  However, having tapped just one male spider from 275 cones makes me wonder whether the species really is established on the island, or whether that individual was a "dead end" pioneer.  Only more sampling will tell.

Mt. Rainier from just offshore of Tahlequah