June 20th, 2006
keeping up with the spiders
As mentioned in this morning’s post, I’ll probably be posting a little more frequently this week. I’ve fallen behind in writing about the interesting things that I’m seeing, so I’ll try to write a few notes to do a bit of catching up.
If you’ve been following my blog for awhile, you’ll know that I’m quite interested in spider behaviour, and particularly, the behaviour of female spiders that like to guard their egg cases. This afternoon, I found another nice example to add to the growing number of accounts.
Today’s spider is a Crab Spider (Thomisidae) — I think the species may be Xysticus emertoni**. I first found her on June 16th, resting quietly on the tip of a stem of the extremely fragrant “Blanc Double de Couvert” rose bush in the garden. The rose is a very old variety that was used for rose oil production, so the blooms are quite oily and sticky. When I first spotted the spider, she didn’t seem to be in a very good location for hunting — being too far away from the blooms to effectivelly ambush any of the insects that were visiting the roses. I checked on her several hours later and she hadn’t moved. I checked again the next day and she was in the same spot as on the previous day. Today, when I visited, I found that she had constructed a small refuge by fastening a few leaves together with silk. I examined the shelter and found that she had attached an egg case to the underside of the “roof”. When I approached, the spider immediately moved into a defensive position and wrapped her legs protectively around the egg case (see above – click on image for larger view). I’ll try to visit her over the next while to photograph any developments and add the data to my records.
And by the way, while I’m on the subject of records, for anyone who is interested in submitting spider observations to the Nearctic Spider Database, visit this page to learn how to do so using the new “visitor comments” feature. What should you submit? Records of sightings should include general location, date and any other interesting observations concerning the spider’s behaviour, habitat, etc… How do you do it? Read the basic instructions, and then look up the species page for the species you wish to report — and away you go.
**Note: The ID on this spider has been edited since I wrote this post. The spider is more likely Xysticus emertoni rather than X. audax.
Tags: Crab Spider, Thomisidae, Xysticus audax, maternal spiders
June 20th, 2006 at 9:18 pm
Bev has been leading the pack re: contributions to species page observations and specimen sightings in the Nearctic Spider Database. Whenever anyone submits an observation, a “name in lights” table is automatically created and available here: http://canadianarachnology.dyndns.org/data/canada_spiders/Contributors.asp midway down the page. Bev’s observations have been very detailed, which far surpass my expectations for these contributions. Very little (if anything in a lot of cases) has been published on most spider species’ habits that casual observations like this go a long way to helping us develop our collective pools of knowledge. The species pages in the Nearctic Spider Database are widely distributed to a number of biodiversity portals and detailed comments like Bev’s will undoubtedly be incorporated into the species pages proper. Each species page has a speech balloon toward the upper-right of the page, which will direct you to the comments form. Navigating through any aspect of the Nearctic Spider Database will eventually get you to individual species pages where you can leave your comments.
June 20th, 2006 at 11:18 pm
This is cool! I have the same species of spider doing the same thing on one of my flowers(Daisy)in my garden…
June 21st, 2006 at 12:12 am
This is the type of behavior that makes it easier to identify with certain animals. We see ourselves in it. When we see what we consider maternal behavior, it reminds us of Mama. It’s the same feeling we get when we see animals playing; it reminds us of ourselves as children or our own children. I’m certainly not the first to point out that it’s why we tend to identify more with predators than with prey animals, since predators seem to engage more, or at least more often, in behavior that humans also engage in. The strange and thought-provoking thing is to see this kind of behavior in spiders.
June 21st, 2006 at 2:16 pm
David – Thanks for adding some additional information regarding leaving comments. I do hope that more people will consider posting their observations to the species pages as it does all add to the collective knowledge base.
–
Jimmy – I hope you’re shooting some photos and recording dates (although the camera does that quite well). Regarding the species, it may or may not be the same. The crab spiders (along with most other spiders) are very difficult to ID from basic appearance. However, it’s usually not that difficult to ID them down to genus, which is really pretty helpful. I’m trying to learn more about spider identification. Very difficult though! (-:
–
Mark – Yes, it is quite thought-provoking when you see this behaviour in spiders — or in certain other creatures. Recently, I was looking at a most bizarre photo in For Love of Insects by Thomas Eisner. I believe it was of some species of Sawfly guarding its larvae!! I wish I had the book here so that I could say more about it, but there’s something almost unimaginable about a winged insect hanging around to look after some worm-like creatures. However, that said, I’ve read about Thorn-mimic Tree Hoppers that guard their nymphs from predatory wasps by kicking at them — and that they respond to some kind of tiny vibrational noise made by the nymphs. I believe that we tend to think of invertebrates as being almost mindless — but we may well be underestimating the level of their thought processes.
June 21st, 2006 at 3:29 pm
I hadn’t ever thought about the protective maternal behaviors in inveterbrates. I’ve noticed it, but not really considered how interesting it actually is. dpr and I have had some discussions about clams and oysters. He likes to go clamming and always eats what he brings home. I don’t eat it, and have remarked (however unwisely!) that clams must feel something like pain when they are in boiling water. He doesn’t think that they do. Humans do think of invertebrates as mindless, but their behaviors definitely suggest sensitivity and awareness in some ways.
Well, what I really wanted to say is, great photo and interesting discussion of this spider’s behavior.
June 21st, 2006 at 11:18 pm
RA – Thanks! I never know what to think about clams and oysters, but I would feel sorry for them. Reminds me a bit of one of my brothers who used to live out east near Halifax. He bought some clams somewhere… I believe from a local fisherman at some wharf. For one reason or another, he didn’t have time to cook them and kept them in a pail with some sea water (his place was on the ocean). He kept changing the water and I guess they were opening their shells and moving about a bit. After a couple of days, he decided that he couldn’t eat them and released them instead. To me, it showed how some kind of familiarity with out food can change our relationship to it. When food comes in a wrapper, we cook it up without giving much thought to the creature it came from. However, when we have to look it in the eye before eating it.. hmm.. seems to change things a little.
July 6th, 2007 at 9:49 am
[…] And here’s an update on the (probable) Xysticus emertoni Crab Spider that I reported on back on June 20th. Seventeen days later, she’s still guarding her egg case inside a small refuge constructed of rugosa rose leaves. Her abdomen is looking quite caved in now, and she seemed so torpid that, at first, I thought she might be dead. However, she became active when I disturbed the leaves around the refuge. She moved to cover the egg case with her body, wrapping her legs around it protectively, and then held her ground while I shot a couple of photos. […]