Walking with spiders – Part 3

Beginning in late summer and lasting until early winter, exploring the woods and woodland edges around White Rock Lake demands a certain sense of awareness and keen observation well beyond the norm.  Why?  Imagine a spider’s web anchored by a line up to 15 feet/five meters long, an orb more than two feet/60 centimeters wide, and a rather large arachnid hanging head-down in the middle.  Now imagine having such webs clustered together where every few feet another spider hangs, each one staggered horizontally and vertically in a way that creates an obstacle course made from silk.  That describes the peak season of barn spiders (Neoscona crucifera).

(2009_10_10_031233)

In some places, up to half a dozen of these creatures can occupy an area of about ten paces.  Some build webs so high that the only sign of them is an anchor line that rises toward the heavens.  Others build webs at about face level with anchor lines running some distance away.  It’s easy to look at the amount of silk and the length of the anchors with a feeling of awe coupled with confusion: how does the spider cover that much distance in order to build such a massive web?  No matter how they do it, they certainly do it well.

The more interesting aspect of this species comes from how variable they are.  It’s not just polychroism (variations in colors), but it’s also full polymorphism (variations in colors and patterns).  Pattern differences often are more subtle than color differences, though running across one that lacks nearly any pattern whatsoever means scratching my head and wondering if I’m looking at another species altogether.

A female barn spider (Neoscona crucifera) hanging on her web (2009_09_27_029782)

N. crucifera is often confused with the spotted orbweaver (a.k.a. cross spider or redfemured spotted orbweaver; Neoscona domiciliorum).  In fact, even I’ve seen barn spiders that were dark enough to be nearly identical to spotted orbweavers save a few minor differences.  In such cases, assuming I can’t tell by size (of the web and the spider), all I can do is note that the spider is one of the two.  (Barn spiders are larger than spotted orbweavers; the former also builds larger webs than the latter.)

A female barn spider (Neoscona crucifera) hanging on her web (2009_10_10_031201)

On the other hand, I’ve seen barn spiders that lacked nearly all markings and the usual colors.  Again in these cases, I’m left scratching my head and later performing diligent research with hope of putting a name with the face.  I often am surprised to discover it’s yet another variation of the same arachnid.  (Of special note is that northern populations of Neoscona crucifera can produce a white variation in females.)

A female barn spider (Neoscona crucifera) hanging on her web (2009_11_08_037657)

By the middle of autumn, a rapid change starts to appear: a change in shape.  Once round and plump abdomens full of eggs suddenly become flat and deflated.  The spiders take on the impression of ending.  Though they can live until the first freeze—and many do—the creation of the egg sac leaves the arachnid a shadow of its former self, an almost weak-looking thing compared to its previous size.

A female barn spider (Neoscona crucifera) resting on dead leaves (2009_11_28_042721)

I admit to an abundance of confusion in the guides and resources used for differentiating these two species.  Certain diagnostic markers given for one actually match some of the broad variations in the other.  The safest way to tell the difference in places where their territories overlap and a specimen matches both species is to use a microscope to look at the female’s genitalia, or to locate and identify the orientation of a very specific indentation on the carapace (this marker is essentially impossible to see in the field except under very specific circumstances and lighting).

Thankfully in my case, all the individuals, though varied, lacked any true resemblance to N. domiciliorum.  Then again, were one to take the guidance on colors and patterns as definitive, then several of them didn’t match N. crucifera either.  What I’ve seen in researching them is a growing body of evidence which indicates a level of polymorphism similar to cricket frogs.

[all photos are of females]

25 thoughts on “Walking with spiders – Part 3”

    1. You’re not alone, LaDonna: I think most people have some level of arachnophobia. But I’m glad you were intrigued by the photos. I have a few more artistic spider images I’ll post at a later time that I think you’ll like as well.

  1. excellent photos of the hairy little friends! They’re a little creepy, no doubt, but they’re still lookers! Thanks for the good info! – During field season in the hill country, some sort of giant orb weaver would stop me dead in my tracks starting mid-May. Yikes. those webs were THICK! I think i quite literally bounced off them more than once. 🙂

    1. Thanks, Jill! As a gift from my mother I lack a fear of spiders, so I’m always on the lookout for them (and I’m always the one hiding a mischievous grin when someone else hits a web and does the requisite “spider dance”–spinning in circles, swatting at their face and clothes, and screaming “IS IT ON ME!?!?”).

      Your experience in the hill country sounds pretty cool. I don’t think I’ve run across many of the very large webs like that, though I’ve seen some that were close. (Related: I did visit the giant web at Lake Tawakoni [see this] when it was in full force. After spending a whole day walking through that magical wonderland, I can’t imagine I’ll ever see anything else that can compare. I also imagine it was the true test for anyone thinking they weren’t scared of spiders.)

  2. We have these spiders all over up here on the farm, and they are fasinating to watch. When they capture something in their web the action gets wild. Awesome photos and info. You spoil us yet again.

    1. You’re too kind, Mom. Thank you! After researching them for this post, I’m not surprised they’re around the farm. In fact, I’d be shocked if they weren’t. Everything I read about them says they’re quite fond of wet woods and woodland edges. Being where you are, it seems like prime habitat for them.

  3. Wonderful photos, I love to see them so up close and personal. We have orb weavers in the garden and I seem to run into a web nearly every morning on my way to feed the chooks. So far I haven’t ended up with the spider attached to me, which suits me just fine.

    1. Thank you, Carol! I giggled at your last sentence about being satisfied with not having one of the spiders land on you when you run into a web. Somehow I think you’re not alone in finding that the best outcome for all involved.

  4. Jason I just love your spider posts. Such elegant predators, and their endless varieties of shape, build and livery take the breath away. From the glossy, high-fashion anorexics to the thugs in armour they get my imagination racing with flights of fancy about what their personalities might be like. (I know I know… it’s wrong to anthropomorphise.) I should probably be painting them, though in what context I’m not yet at all sure.

    1. You’re too generous, Clive! I’m glad you like these critters. One thing I’ve always loved about them is their personalities. For example, jumping spiders have always been my favorites because, as an entomologist friend of mine once said, they have looks and charisma, which is an enviable combination. Just the fact that they display curiosity was enough to win my heart.

      The genus Portia, most notably the species Portia labiata, has to be the real turnaround for me when it came to thinking of spiders as more than pre-programmed assassins. The entire genus is known for some extraordinary abilities, but P. labiata has shown indications of intelligence that go against everything we think about spiders: forward thinking, learning capabilities, complicated decision making, unparalleled three-dimensional spatial memory and planning, and even what could be an ability to actively communicate with others of its kind with a form of sign language. After reading an article about the species and doing more research, it occurred to me then that spiders were a lot more complicated than I’d ever imagined.

      Oh, I definitely think you could do real justice to spiders in your art–you more than anyone I can imagine–though I admit I haven’t the creative wherewithal to suggest how. But I have no doubt that should a context come to mind, your creativity, artistic ability and love of nature would ensure a masterful representation.

  5. Well if I ever do it it’ll be your photographs next to me as reference!

    I love the sound of what you say re. Portia. (And what a wonderfully Shakespearian moniker!) I think I’ve always intuited that spiders were brighter than most give them credit for! And I really like the photographs of the one above, glowing garnet red like it has a fire within. Marvellous.

  6. I love the burnt orange glow of the legs in that 3rd picture. I think one of your gifts is your ability to identify just about any wild thing. I will usually give it a good try, then stop at whatever level I’m reasonably sure of. Most of the time I’m too anxious to get on with my story or my point to put the time in to attempting ID at the species level. Your blogs do as much for increasing my ability to identify wildlife from simple memory as do my shelf of field guides. Thanks, Jason!

    1. You’re far too kind, Amber. Thank you! I admit I love to learn; I also want to know the natural history of the subjects; couple those with me being a big ol’ geek at heart and it turns into a constant search to identify and understand. But I can’t always pull it off: for the life of me I couldn’t pin down the ID of that polypore (bracket fungus) in your last ID challenge. Maybe with a bit more time…

      You certainly brightened my day. I’m glad to hear it’s useful. Sometimes I fear it comes across as too nerdish, too knowing, too much information. It’s nice to know that maybe that’s not always the case.

    1. Too funny, Clive! And not too far off base. I’ve been thinking of doing something akin to seasonal guides to the lake where I live–photo books with a mix of anecdotes and natural history, though more artistic than scientific. I don’t know how I’d pull it off or even if I have the quality of images necessary, but it’s an idea tumbling around in my head.

  7. I was determined to get over my fear of spiders by learning more about them..But the spider gods have tested me by sending little house spiders to lurk in an empty coffee cup or by my tissue box on my night stand. I am pleased to say that I no longer run screaming from the room.. but would you ask them to please stay out of my coffee cup.

    These are interesting spiders and I do plan to get out and look in the spring after the foot of snow melts…

    ‘Damn it Ollie ‘just broke into the Coffeemate powder. He looks like a powdered cocaine user…sigh…

    My COS Autumn Meadowhawks Mating.

    1. Hysterical, Michelle! I admit finding a spider in my coffee cup would leave me a bit cross: the spider needs to find its own cup, darn it, or at least ask to borrow one before diving right in.

    1. What an interesting twist, ksdolittle. Many people who dislike spiders tolerate or are intrigued by jumping spiders (tarantulas are a second common exception). I think it’s fascinating to see that general rule turned on its head. For me, I like them all, and I admit jumping spiders are my favorites.

  8. The photos are wonderful. I tried repeatedly last summer to capture good, deep-focus images of spiders, and found them inexplicably difficult to capture in a nice clear image. Katydids, crickets, beetles and other similiar-sized critters with smooth surfaces were no problem, but the spiders elude me.

    Nice job — Any tips?

    1. Thank you so much, James. I appreciate the compliment.

      On the photography question, I have to admit my techniques are rather contrary to most macro images. That is, I don’t use a macro lens. Don’t get me wrong: I want to get one eventually, but for now I make do with what I have.

      All of these were taken with a 400mm telephoto lens and were shot hand held. Given the minimum focusing distance of the lens (~2m), this makes it easier to get good DOF without terribly high f-stops. It also means not being close enough to disturb the subject. (Other examples of this technique with insects can be seen here and here.)

      It has its limitations, of course. The smaller the subject the more difficult it becomes to grab sufficient quality, and a moving object is easy to lose given the small yet highly magnified field of view. And it will never draw out details comparable to what a macro lens can do. Still, I’ve enjoyed challenging myself to make it work.

      On spiders in particular and small subjects in general, my technique is the same as if I was photographing a distant bird or a sunning alligator: getting as close as possible without disturbance, using the smallest f-stop possible to get the right DOF without excess noise (with this setup, that’s usually around f/8), compensating for available light (I don’t use flash for anything except in extraordinary circumstances), using the lowest ISO possible, and extending the exposure time to draw in details without overexposing the image or picking up motion blur.

      All of that to say I’m sorry I don’t have a grab bag of tips that would apply specifically to spiders, or even any that would apply to general macro photography. I really wish I could offer something more concrete.

      By the way, congratulations on the Beetles in the Bush job! I’ll comment there as well, though I figured it wouldn’t hurt to say as much here.

  9. Not sure if you still check this place but I’ve a confession to
    make. I’ve an immense interest in spiders. Especially web making
    ones. The other day I bumped into n.c. in my back yard. She built
    up her house between tree leaves with a string of silk reaching the
    ground 1.5 meters down. I couldn’t help myself and adopt this guy.
    I’ve bought over 200 bucks equipment to create a glass habitat for
    her. She was first scared but then loved her environment. She
    builds her web always facing the area where the daylight is the
    strongest during the day. Not sure why. She retreats herself during
    day times and pretty much sleeps off it. She’s usually curled in
    between aquarium plant leaves. When sun sets she wakes up from her
    sleep and goes on her business to build an awesome orb web and then
    she patiently sits in the center of it. Then I release a fly into
    enclosure and she eventually feeds on it. Once the sun is up and
    it’s about 9-10am she recycles her home and retreats to a corner to
    pass the day out. She’s a fascinating creature. I’m going to
    release her at where I found her once she matures up; so the nature
    can continue to take its course. I’m definitely going to miss her.
    She is a small baby now.

Leave a Reply