The “slower” days of winter in the spider world aren’t slower because there aren’t any spiders to find, they’re slower because they’re harder to find. I did a few sweep net samples in November and December in Frick Park to see what was out there and scooped up some spiders that were new to me. Frick Park is Pittsburgh’s largest city park and is primarily wooded with over 600 acres of steep slopes and streams.
A sweep net is a heavy duty version of a butterfly net, usually made of canvas. I have homemade sweep nets made out of clothes hangers, pillow cases, and old broom handles. They are sturdy and only cost the time it took to make ’em. They can run ~$30 new. It’s called a sweep net because you’re supposed to sweep the opening back-n-forth against weeds and grasses. And you have to do it hard. The idea is to knock spiders, who can hold on really well, into the sack for collection.
On a late November afternoon I did a few passes with the net in a patch of golden rod at the 9 Mile Run Trailhead off of Commercial Street. Using this technique, I easily caught twenty spiders. These are twenty spiders I would’ve never seen just by standing there and looking, especially since these were small spiders (none of them more than 5mm in length), most of them immature.
Once you’ve done a sweep, you dump out everything you’ve gathered (twigs, leaves, ants, beetles, caterpillars, spiders, etc) onto a light colored sheet and catch the spiders in separate vials. I use an aspirator which is a small jar with two tubes sticking out of a rubber stopper. You basically vacuum up the specimen by sucking on the end of one of the tubes and the spider goes into the jar through the other tube. There is a screen on the end of the aspirating tube so you don’t inhale the spider down your throat. That would be unfortunate!
The November sweep produced seven lynx spiders, seven “striped abdomen” spiders, one long-jawed orb weaver who went missing, one running crab spider, one “I have no idea” spider (and still have no idea), one “possibly funnel weaver” spider, one bowl and doily spider, and one small, possibly injured wolf spider that didn’t make it. When I note an unknown spider (unknown to me), I usually refer to it by its most standout characteristic, like, “striped abdomen spider” or “crazy bent knee spider” and use those standouts to help identify the spider when I can get a better look.
The top left photo above is one of the “striped abdomen” spiders which I later identified as immature ‘open field orb weavers’ (Araneus pratensis). These spiders stay small even when full grown and make small orb webs among meadow plants. I had five immature males and three females. Over the months, some died and some matured. The top center photo was taken this month and is a mature male. It seems to have lost its stripes! I introduced a few males into a female’s container and THIS happened to one of them. The second introduced male was much more passive, so much so that he died of old age before he even approached her.
The top right photo is the tiny Striped Lynx spider (Oxyopes salticus) from the Oxyopidae family. They are active hunters, quick, and pouncy with shimmery scales and spined legs. The prominent stripes on the head and abdomen are a good diagnostic. Under a microscope, lynx spiders have eight eyes in a hexagon pattern high on the head.
The bottom left photo shows what I noted as “possibly funnel weaver” but the microscope revealed more clues. The markings on the head are characteristic of what are commonly called ghost spiders (Anypaenidae family) NOT a funnel weaver. Ghost spiders are free-ranging hunters and don’t use a web. They have special claw tufts on the ends of their legs that enable them to “stick” to surfaces and they can quickly disappear among the vegetation…like ghosts. There are thirty eight different kinds of ghost spiders in North America. This one was Anyphaena celer.
The bottom middle spider is in the Philodromidae family. They are flattish spiders and have a star-shaped stance at rest. Their second pair of legs are longer than the others, which is a good diagnostic at a glance. These spiders are short-distance sprinters and often run in circles on smooth surfaces. This one was an immature male with gold and purple iridescence.
Finally, the bottom right was, indeed, an immature, female bowl and doily spider (Frontinella pyramitela). These spiders make cup-like webs on the ends of twigs and such and are found hanging upside-down on the bottom of the web. They have beautiful zebra-like markings with a hint of yellow. Again, a small spider no more than 4mm when fully grown.
My second sweep in Frick Park was in late December along Tranquil Trail. The area was mostly dead golden rod stalks and shrubbery a few feet from Fern Hollow creek. I caught seven specimens this time: two Tmaris angulatus, four immature orchard spiders, and another spider I still haven’t ID’d! Again, all spiders were very small and immature.
The first photo shows an orchard spiderling (Leucauge venusta) from the Tetragnathidae family. This guy was a speck! I could instantly ID it by the orange blaze on its belly. I started out with four of these spiderlings and ended up with one. Turns out the dominant spider ate the other ones. I wasn’t offering them any food because it’s hard to find tiny insect food for tiny spiders. I wasn’t even sure the spiderlings were actually eating since they can go for awhile without. I was wrong! Keeping spiders indoors throws them off of their seasonal timing. Instead of overwintering, they remain active. They eat and continue to grow. My orchard spider molted into a long, slender male (top center photo) who has matured early. His outdoor counterparts are probably still in the penultimate adult phase. These spiders are found throughout the summer in Frick Park making nearly horizontal orb webs. They hang out in the center of the web, upside down with their orange blaze and greenish bodies shimmering. They are very pretty spiders!
The top right and bottom specimens were indeed Tmaris angulatus. Unfortunately, there is no common name for this spider. At least its not too complicated to pronounce – it sounds how it looks. T. angulatus is actually a crab spider (family Thomisidae), but is an oddball with its angled head and pencil-like posture. They are unique and easy to ID once you know what to look for. These spiders completely blend in on twigs and dried plant stalks. I would’ve never seen them if I hadn’t used a sweep net!
Every year, the Frick Environmental Center hosts an Earth Day celebration which is free to the public. This year it falls on April 26th and 27th. It’s an amazing weekend with a community campfire, exhibits, a volunteer event, and naturalist-led walks and hikes. I will be there leading “Spider Tracks” on the 27th and pretty much doing what I just wrote about, except with a crew of excited (and sometimes ambivalent) spider-curious people. For more info, please visit the PROGRAMS page. I look forward to collecting a giant Frick Park Spring spider sampler, but more importantly, the awesome part is getting to educate people and watching them convert from fearful to enthusiastic when they find a “really cool spider”! Join us!