Well, these aren't exactly spiders. They are arachnids called Harvestmen. They are also called Daddy Longlegs. Craig Tooley photographed a group of them, which is called a snarl.
I wonder just how many Harvestment are in this snarl. Dozens, yes. Hundreds, perhaps!
Here's what Craig Tooley wrote, “My neighbors, John Holloway and Elaine Reed, asked me to come over and take a few pictures of this interesting collection of arachnids or Harvestmen. When I asked John what he knew about them, he said, ‘There are many species of them around the world, with fossils of them going back 400 million years. They are called Daddy Longlegs, though they are not a true spider.’”
These arachnids are very beneficial, eating many other insects including termites. They only have two eyes, as compared to spiders that have six or eight. They are entirely harmless to humans. John and Elaine’s visitors have formed this snarl for the same reason Sea Lions raft together – for protection against predators, and perhaps for warmth.
Thanks to Craig for allowing me to share his interesting photo with you here. To see much more of Craig's wildlife photography, here's the link to his website: http://ruffimage.com/