Oyster Blog — Tideflat Critters

These are moon snail egg cases, not pieces of rubber that someone littered. Moon snails use sand and mucus to make the pliable cases. The eggs hang out in the case for a couple of months, then break free and become free-swimming larvae for a while before they settle down and become fully-realized moon snails. We know some humans who've followed a similar trajectory.

These two crab were just, um, minding their own business when they were rudely flipped over and inspected. The crab at the bottom of this photo is male, the crab at top is female. Notice the difference in the shapes of their abdomens? Male crab have a longer, thinner abdomen; female crab have a shorter, rounder abdomen. They mate in the spring and summer. The process takes several days. For a beautiful description of crab sex go here. It's illegal to catch female crab, so all the crab you see on the market are, or should be, males. These crab...

Everybody knows this guy! But who knew sand dollars have such hairy bottoms? This is what they look like BEFORE you see them for sale in jewelry-supply stores. Interesting fact: last spring researchers at the University of Washington discovered that a sand dollar larvae will clone itself, and split in two, when it smells a dover sole... the theory being that the sole will only be able to eat one of them. Maybe this will give Michael Keaton some ideas for a career comeback.

The geoduck clam is the biggest clam in the world. Pictured here is a teensy two year old, but they can live to be 150 years old, or older. They frequently weigh more than 5 pounds. And yes, they're ridiculous. Geoduck live deep in the sand, and while they can retract their neck to avoid predators, they can't retreat completely into their shells, like horseclams can. One geoduck with broken shell, two horseclams. Eye of horseclam Disco Duck

Underside of a sea star, up close. The entrance to the mouth is covered by a mass of tube feet. The mouth opens up into the mobile cardiac stomach, which leads to a fixed stomach, which leads to the anus, which is on the top of the star. Tube feet suctioned onto a rock. Read more about sea stars here.