Idotea wosnesenskii and Hemigrapsus nudis

Here are some additional finds from our road-end explorations. I make an attempt to identify the creatures when I can so that I can slowly learn about the ones we commonly find. A great website resource is provided by Washington State University: http://www.beachwatchers.wsu.edu/ezidweb/animals/Idoteawosnesenskii.htm

This little isopod is related to the pill bug and wood lice! They were very cute – when exposed, the big green ones would cover the smaller darker ones. We wondered if that was a male/female behavior, or adult/juvenile. We made a little habitat for them and they began to relax and move around again. Apparently birds and fish feed on them. Some have even said long bristle worms eat them.

A pretty big crab that Sam found under a rock. His purple claws give him away as Hemigrapsus nudis, one of many varieties of shore crabs (Hemigrapsus sp.). Thanks again to the WSU website mentioned above for this quick ID! He creates little habitats for them in his hand and walks around with them for a bit, then puts them right back under the same rock they came from. This one is pretty big. When he began blowing bubbles we put him back home. I have read that blowing bubbles is how they create more air for themselves, but I am not sure in this situation. Perhaps being out of a damp environment made it harder to do gas exchange so this bubble-blowing created a more humid environment? Could also be a stress reaction. It’s not the first time I’ve seen this, though. On Kailua beach a crab was just sitting in the sand undisturbed and blowing bubbles. A great mystery continues…

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