Female Orb Weaver Spider

2012 May 9

I found this late in the season, on November 19, 2011. It was dragging itself slowly down the hall next to the big windows in the building I work in, so I scooped it up and brought it home.

I originally thought that this was a male, mainly because it was smaller than the other spiders I normally saw on those windows, and it appeared to be wandering around. But, after this posting first went up, I was advised in the comments that spider expert Dr. Richard Bradley said it was actually female, of a different species than I had thought it was. Thanks, Dr. Bradley!

Anyway, she was still alive when I got home, but badly dehydrated. So I gave her a wet piece of paper towel, which she immediately latched onto and started sucking on. I could almost see her plumping up.

Spiders’ legs are essentially hydraulic. They need to be pumped up with fluid to extend them (they have no extensor muscles, the musculature is only to pull them back in again). This is why spiders generally die with their legs all scrunched up, because they quickly dry out and lose pressure. So, as she rehydrated herself, she gradually regained the ability to unfold her legs and actually expose her face.

She had a cluster of four eyes arranged approximately in a square in the center of her face, with another pair on each side that are well away from the center cluster. This arrangement of eyes is characteristic of the Orb Weavers, family Araneidae

As it turns out, she was at the end of her lifespan when I found her. Even after drinking, she wouldn’t eat her fruit flies, and died about a day later. But, since she hadn’t dried out yet, I was able to flip her over for a shot of her underside (something I generally don’t get a chance to photograph for most spiders).

She is one of the many and varied big, gray orb-weavers that spin their webs outside the windows of the building every year. They usually stay outdoors, but sometimes the windows get opened and a few of them sneak inside. I originally thought she might be a Barn Spider, Araneus cavaticus, of “Charlotte’s Web” fame. But Dr. Bradley says she is actually in the Larinioides genus, and is probably Larinioides sclopetarius (although there is a chance that it is the similar species Larinioides patagiatus).

Spiders do pretty well on those windows. That side of the building faces Portage Lake, and the halls stay partially lit all night. Since the hall runs right past the windows, that means the windows are sufficiently lit to draw bugs like midges and mayflies that emerge from the lake. So the spiders that build their webs there are well fed, and become fat and numerous.

Except for when the Cedar Waxwings come by. In late summer, I sometimes see the waxwings hovering[1] in front of the windows, picking these grape-sized spiders out of their webs.

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[1] Sometimes the waxwings will get tired of hovering, and rest on the window ledge. And then when they are ready to take off (after spotting me watching them), they don’t spread their wings and fly off straight. Instead, they give me kind of a dirty look, and then just lean over and topple off of the ledge with their wings closed. It just cracks me up. I don’t know how long they fall before popping their wings open and flying off, but it’s well after they drop out of sight, and looks to be several feet at least.

6 Responses
  1. Kathleen permalink
    May 10, 2012

    What a beautiful guy- the spider for being himself- and you for trying to resuscitate him. Super photos as usual! Thank you.

  2. Kathleen permalink
    May 10, 2012

    This is a note from Dr. Richard Bradley from the Ohio State University, who is the president of the Ohio Spider Society. I had sent him your beautiful photos.
    “It is a beautiful set of photos of an adult FEMALE of one of the two slightly confusing
    Larinioides. Probably Larinioides sclopetarius, but could be Larinioides patagiatus.
    I’ll need to check details later but my time is short this morning…”

  3. May 10, 2012

    Thanks, Kathleen! I’ll go back and correct the sex and species in the posting when I have time later today.

    [Later today] . . .

    Ok, fixed!

  4. Kathleen permalink
    May 10, 2012

    More from Rich Bradley: ” I had a closer look and I’m pretty sure it is Larinioides sclopetarius.”

  5. Holly permalink
    July 1, 2017

    I found this spider above my door . It has a giant Web over the outdoor light. It is huge, has a rounded kinda oval like Hump and it’s covered in fur, and has a white spot on the Hump as well. I don’t know what kind of spider it is so I don’t want to mess with it. And it’s above your head as soon as you walk out the door. I need to know what it is because I have to know if it is safe to remove it.please let me know. Thanks . I have a picture of it. One as good as I can get it.

  6. July 3, 2017

    Holly:
    I don’t think you have anything to worry about. The only spiders in North America with “medically significant” bites are black widows and brown recluses, neither of which spin webs out in the open like that. And it isn’t going to come down from its web to mess with you in any case. It would have no reason to do such a thing. Its web is admirably situated to catch things that come to the outdoor light, and it is not going to leave such a fine spot. If you just leave it where it is, it will be absolutely no danger to you.

    Still, if you really feel the need to get rid of it, just sweep it down with a broom and shake it off outside. I have messed with a lot of spiders over the years, and I have never had one do anything other than try to get away from me as fast as possible.

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