Thank you very much Cinda and that is very observant of you. You are so correct about the silk thread and not that many people are aware of that.
For those that didn't know this already, Crab Spiders don't use a net to capture their prey, rather they just sit patiently on top of a flower or similar, waiting patiently for a pray to come close enough and then bang shuts the trap, dinnertime
. They use silk threads only to move around. Sometimes the small ones use them for a phenomena called ballooning, where they release a thread and let the wind carry them, sometimes over large distances. In this case the spider perhaps thought that I was a bit too inquisitive with my camera and tried to escape