Another New World: Underground Crab Network

You know how you can walk past the same place several times and never notice something and then once you see it, you can't believe how obvious it was?

Last week in Hawaii, my eight-year-old and I went for an early morning walk on the beach. Jetlag seemed to affect each of us differently - he had the I-can't-sleep-past-4am version of it! After a long walk along the sandy beach, I spotted a crab. Just as I pointed it out to my son, the crab ran down a hole. As we waited for him to come out, another one (or him?) popped up from another hole.

Suddenly, we realized the beach was covered with these little holes and tiny little crabs popping in and out of their underground network. We never saw that many crabs or their homes after that, but that morning we must had perfect timing to see them all rising for their morning stroll on the beach. Some quick research tells me most people call them sand crabs and sunset is the best time to spot them - apparently, in our case sunrise worked fine as well.

Most of the holes were tiny (see comparison with size one foot at left), but we had to wonder what kind of crab lived in the one giant hole we found. Look at the regular sized hole at the top and then the one 20x bigger at the bottom. Thankfully, we didn't meet him at the beach!