Now, finally, a week later, I'm putting these Intertidal Zone pictures up.
If you want to know where this was, it's Fort Stark in Newcastle, NH. Very nice place. Here are some "Look how pretty it is" shots.
The rocks had cool layers to them, like ribbons.
And now, the lab. We lay out two of these little plots and counted all the organisms in them-- the seaweed, snails, barnacles, and mussels. Look at all the barnacles! That was annoying to count-- there were over 400.
There were three kinds of snails. The one on the far left is a carnivorous snail, not native to the region. It eats by latching on to other shellfish and scraping a hole through the prey's shell. The next one is also not indigenous-- we know of it as the common periwinkle. The third one, the tiny one, is the native aquatic snail in this region, also a periwinkle.
Also, I found an empty sea-urchin shell.
It's a great area, lots of tidal pools and fun to explore.