Up, Up, and AWAY!!!

I don't know how many of you saw Charlotte's Web, but when I watched it for the first time, the part after Charlotte died and Wilber was all alone and taking care of her eggs and then they all left him except for the one that wanted to learn about Charlotte, it was so moving and beautiful that I cried. Touching animal movies usually get to me, but it also got my curiosity going. When they all made little web parachutes and waved good-bye as the wind took them, I was in wonder at the fact that they could fly...

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It turns out I was half right, they can float! Just because they don't have wings doesn't mean they can't soar high in the air. Ballooning spiders aren't a species of spider, for a lot of spiders can use the ballooning technique to disperse themselves to other areas. Balloning is mainly seen in younger spiders, which are also lighter, who use it to get to places that can become their homes or to escape from predators. Some adult females of the social Stegodyphus species have also been seen to use this ballooning method on hot windless days. First they send out silk (web) with enough form so that it can lift the spider and so the spider can use it's own body to drag, or anchor itself, and then they go into a tiptoeing behavior where they get on the tips of all their legs and point their abdomen out and wait for themselves to be taken away. Ballooning spiders have been seen miles out into the ocean far away from mainland and, using this method, spiders have colonized many islands. They really know how to get around!

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http://www.livescience.com/animals/060712_parachute_spiders.html

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http://en.wikipedia.org/wiki/Ballooning_(spider)

Posted by Ada Marie Flores (8)

Update (11/11/08)
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So many of you have asked about how they float. Well besides using themselves as anchors so that they decide how far they travel, these different species of spiders, that can balloon, use wind currents to pull them along. The reason that some spiders are sometimes found far out at sea, is that their silk "balloons", that can sometimes consist of only one thread, molds to and gets carried on the eddies of turbulent air which carries them further than weaker, shorter winds.
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Someone else asked a question in regards to the species of spider whose adult females balloon in arid, windless conditions and how this is achieved. The approach used to acquire this "flight" is actually different from the "normal" ballooning method. Not only is it not dependent on the wind, the spider utilizes the rising temperatures to gain its "lift". That's not the only difference either. In the "normal " ballooning, the spider only needs to send out about one string because the wind is generally strong enough to carry its light form, but because these females are adults, and therefore heavier, they make a complex triangular sheet of tens to hundreds of silk strands to help carry their form. Texas seems to be a good place to see these spiders balloon.

http://www.bbsrc.ac.uk/media/releases/2006/060712_spiders.html