Saturday, February 18, 2017

17-Feb-2017 Olympia & Lacey, Washington

Site location map. Click to enlarge.
The weather still wasn't dry enough for a full spidering trip with Rod Crawford, but it was just fine for tapping fallen conifer cones.  I decided to head to Thurston County to see what I could find.

I first tried looking for fallen pine cones in South Sound Center in Lacey, but had no luck. Like so many malls in western Washington, black pines (Pinus nigra) are a dominant feature in the landscaping there, but the needle litter and fallen cones had been removed by groundskeepers. In fact, a crew of groundskeepers was thus occupied while I was there.  Sadness.

Towering Jeffrey pine
Luckily I didn't have far to go to find my first cone source. I'd driven just a few hundred feet down Pacific Ave. when I spotted a magnificent Jeffrey pine (P. jeffreyi) towering over the realm. The native range of the Jeffrey pine is mainly the Sierra Nevada mountains in California, so it was a real surprise to find one growing in Olympia, Washington. But it was conveniently located at the edge of a parking lot in an area apparently untouched by groundskeepers, and it was gorgeous, so I was happy enough to come upon it.

My excitement faded, however, when I realized that this tree's fallen cones were poorly opened and few in number.  Still, I did collect a female Tachygyna ursina (Linyphiidae) from the 19 cones I tapped, a species not previously recorded in the gridspace. So at least there was that.

Double row of Douglas-firs
Fallen Douglas-fir cones
My second sampling site was located in St. Martin's Park in Lacey. A double row of Douglas-fir trees (Pseudotsuga menziesii) borders much of the park and had dropped a wealth of cones and needle litter undisturbed by groundskeepers. The scales on Douglas-fir cones usually close in damp weather, but not always entirely.  I was able to find plenty of cones with scales open far enough to harbor small spiders.

Grammonota kincaidi females
Tachygyna vancouverana
I tapped 50 cones and collected 14 spiders.  Nine of the 14 were Tachygyna vancouverana -- 8 females and 1 male. I often tap T. vancouverana from cones in western Washington, but usually it's just a few individuals per 50 cone set. However, I have tapped crowds of 16 or 17 of them a few times, so finding 9 was unusual but not exceptional.  I also collected 2 female Grammonota kincaidi from this batch of cones, another linyphiid that I've only tapped from fallen cones once before.

Wednesday, February 15, 2017

12-Feb-2017 Ferndale & Blaine, Washington

Site location map. Click to enlarge.
A lovely break in the winter weather gave me an opportunity to return to Whatcom County to continue my search for the European crab spider Ozyptila practicola (Thomisidae).  My destinations: Ferndale and Blaine.

Black pines bordering the Ferndale
Park and Ride lot.
The Ferndale Park and Ride lot was my first site.  A row of black pines (Pinus nigra) growing along the eastern property line had dropped plenty of cones. Most of them were poorly opened, but I managed to find 50 that were open enough for O. praticola, if present, to squeeze into. All I tapped from those 50 cones were three juvenile spiders: a linyphiid, a dictynid and a theridiid that was probably Platnickia tincta. Not a very auspicious start to my sampling day.

Mt Baker, as seen from the Haggen
parking lot
Heading into town I spotted another row of black pines, this time bordering the Haggen grocery store parking lot.  Although the cones were more open than at the previous site, I didn't find even one spider in the 50 that I tapped.  At least I had a nice view of Mt. Baker while getting skunked!

Black pines bordering picnic area
next to the Nooksack River
My third and final location in Ferndale was a pleasant picnic area overlooking the Nooksack River. The cone source was again a line of black pine trees bordering the parking area. The cones here were generally well opened, and lay on a thick, sumptuous bed of needle litter.

The fallen cone microhabitat
I tapped 100 cones and collected 15 spiders.  Eight of them were juvenile Enoplognatha probably-ovata (Linyphiidae).  Also present were a pair of penultimate male Xysticus probably-cristatus and another pair of Philodromus juveniles.  The only identifiable species, and perhaps also the only native species present, was Tachygyna ursina.

Black pines on C St.
in Blaine
The last two sampling sites of the day were in the border town of Blaine. The first site consisted of three black pines in a parking lot.  I found 91 cones to tap, all laying on thick needle litter.

Dictynid female from C St. cones
turns out to be Lathys humilis
Those 91 cones produced 10 spiders, the most interesting of which was a female dictynid that I haven't yet identified.  I also tapped several female T. ursina and T. vancouverana from these cones, as well as juveniles from three of the more common introduced species. Update: The dictynid was Lathys humilis. Additionally, a spider I identified as T. ursina turned out to be the undescribed T. sp. #4.

Black pines at Blaine post office
My final cone source for the day was a row of black pine trees growing along the fence line of Blaine's main post office.  Tapping 50 cones, I collected 11 spiders and 4 to 5 species.  The only mature spider in the set was a male Erigone (Linyphiidae).  The rest were juvenile dictynids, Xysticus probably-cristatus and E. probably-ovata.

The mix of spiders I tapped from pine cones in Ferndale and Blaine was pretty typical of what I find in the urban Interstate 5 corridor.  But I was frankly surprised that I didn't find any O. praticola in cones in either city.  This is especially true of Blaine, which is only a few miles from locations in British Columbia where O. praticola has been collected.

Ozyptila praticola sampling sites in WA and B.C. Blue or purple: Confirmed with
adult specimen; Yellow: Juvenile likely O. praticola; Red: No O. praticola
found. Note: B.C. records via Bennett et. al 2014