Sunday, November 26, 2017

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 CryptachaeaEnoplognatha, and Theridion, as well as the linyphiids Erigone, LepthyphantesTachygyna, 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.

Wednesday, November 15, 2017

10-Nov-2017 Bremerton & Southworth, Washington

Site location map. Click to enlarge.
When I tapped cones in Bremerton a few weeks ago in my ongoing search for the introduced thomisid Ozyptila praticola, I didn't manage to take any samples in the heart of the city south of the Port Washington Narrows. I returned this day to remedy that, as well as to take samples in Gorst, Port Orchard, and Southworth. Given that it had rained the day before, I knew the fallen cone microhabitat would be soggy. But it was now or never, since the long-range forecast indicated that this would be the only day in the foreseeable future with a low chance of rain.

Near Manette Bridge, Bremerton
Not entirely soaked
I had prepared a long list of potential collecting spots using Google street view, and was delighted to find numerous, accessible western white pine (Pinus monticola) cones at the site closest to the ferry dock: a hillside along Washington Street at the west end of the Manette Bridge. As anticipated, everything was wet from rain the day before. Cones under the trees' drip lines, however, were at least dry on their undersides. I tapped 50 cones and collected only 7 spiders, but 2 or 3 species: Grammonota kincaidi and one or two species of Erigone.

Hmm, maybe not.
Usually when potential collecting spots don't pan out it is because the tree is on private property posted with "no trespassing" signs, or the cone scales are not open. The latter frequently occurs with cones of the introduced black pine (Pinus nigra), but also cones of the native Douglas-fir (Pseudotsuga menziesii), which close their scales when wet. That means that during rainy weather, the most reliable tree to find open cones beneath is white pine. But accessing the cones of white pine trees, even those growing on public property, can still be a challenge. The magnificent white pine tree growing immediately south of Manette Bridge (left), for example, turned out to be inaccessible without a kayak or a rappelling rig. Well, at least it was a more scenic no-go tree than those growing along Route 3.

Across from Evergreen
Rotary Park, Bremerton
Soggy but fruitful
My second site consisted of a lone white pine in a grassy field across the street from Evergreen Rotary Park. I only found 32 cones to tap, but they produced a surprising 51 spiders and two more identifiable species: the introduced theridiid Cryptachaea blattea, and the native Phrurotimpus borealis (Phrurolithidae). The high overall number of spiders in this sample resulted in large part from the presence of 16 juvenile Enoplognatha probably-ovata, an introduced theridiid I often find in urban cones.

Park & Ride pines
Male (top) and female (bottom)
Phanias albeolus
I had absolutely no luck finding open, accessible cones in either Gorst or Port Orchard, so proceeded on to the last collecting site on my list, a Park & Ride lot in Southworth. Happily, dozens of at least partially open cones had accumulated under three white pines growing near the road. I tapped 65 cones and collected 34 spiders and 3 species, including a pair of mature Phanias albeolus (Salticidae). The P. albeolus were an unexpected find, since we usually find that species in conifer foliage and forest understory. I've never tapped if from fallen cones before.

As with my Bremerton-area samples from a few weeks ago, I found no Ozyptila praticola or even any juvenile Ozyptila in any sample this day. If it is present in the area, it is hyper-localized.

Perhaps this Pacific tree frog (Pseudacris regilla) was also searching for spiders

Saturday, November 4, 2017

28-Oct-2017 Bremerton & Silverdale, Washington

Site location map. Click to enlarge.
After recently finding the introduced crab spider Ozyptila praticola (Thomisidae) near the ferry terminal on Bainbridge Island, Bremerton became the next logical place to look for it. Accordingly, I hopped on a morning ferry from Seattle and tapped spiders from 8 sets of fallen conifer cones in the greater Bremerton area.

A typical black pine grouping,
this one in Silverdale.
The native western white pine (Pinus monticola) is a minor but common part of the forest in this part of Kitsap County, but I was unable to find any that were accessible; they tended to grow on the highway margins or in private back yards. However, there were lots of black pines (Pinus nigra) within reach. This is an introduced species commonly planted on commercial property in this region.

Kitsap Peninsula. Blue & red
pins show where I have and haven't
found O. praticola, respetively.
The long and the short of it is, I tapped a total of 357 fallen conifer cones and collected 33 spiders from 6 families. Five or six species were identifiable, including the native linyphiids Erigone dentosa, Grammonota kincaidi and Tachygyna vancouverana and the introduced theridiids Cryptachaea blattea and Theridion tinctum. All in all, it was a fairly typical set of cone spiders from central Pugetopolis, except that it didn't contain any Ozyptila praticola or even any juvenile Ozyptila of questionable identity. I have yet to find any O. praticola on the Kitsap Peninsula, despite having found it on neighboring Bainbridge Island and Vashon Island.

View from the ferry: Manette Bridge spans the Washington Narrows, linking
the two halves of Bremerton. The Olympic Range provides a scenic backdrop.