Friend or foe?

These two little crabs were going at it for a minute or two. At first I thought maybe a territory battle. but I'm not so sure. Perhaps a mating ritual? I just can't pretend to be able to get into the tiny little mind of a crab. I watched 100's of the little buggers for about an hour. How do you think you could stand never going a foot beyond your hole in the sand? Just like people...there were big ones, little ones, dirty ones, and some who were oh so pretty. In my search for birds, sometimes we forget the tiny little creatures. I went back on Sunday only to find my new crabbing spot completely covered with water. Duh...there are high tides and low tides.