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

No comments:

Post a Comment