Search

A Study of Moon Snails. "How can they even fit in their shell? They are so big!"


We encountered a moon snail on the beach today. We held the underwater snail in our hands. The shell was about 3 - 4 inches long (the smaller snail pictured above, with closed entry). A discussion among children:

"Wow, this is heavy."

"I think there must be a snail at home in there."

"Why is the part where the snail comes out hard?"

"I think it's like a little door it closes when they're scared or maybe they want to sleep."

"Hey, little snail. Or big snail. Are you home?" Tap, tap on the 'door'.

"We better put them back down near the water. That's where they like to live. The moon snail could die."

Later when placing a stick to measure the flow of the tide we encountered another moon snail, only this time the snail was oozing out of their shell. Those of us that discovered this moon snail ran quickly to join the others to share the wonder.

"Look at this! It's a moon snail, but they are outside of their shell!"

The kids used very gentle touch to explore the texture of the snail and shell.

"Look how big the snail is! How can they even fit in their shell! They are so big."

"Yeah, really really HUGE! And the shell is like this," a child says gesturing with wide arms and hands close together.

"Do you know any other animals that can look big and small?" an adult asks, "Like maybe a slug?"

"Or a worm."

"Yeah, how do some animals do that?"

We carefully returned the snail to the water. "Make sure to put it with the baby one," the child said, referring to the smaller moon snail found earlier. Once placed back in the damp sand it grabbed on like a suction cup.


We've seen a few other items on the beach that it turns out are related to moon snails. Have you seen clam shells with perfectly circular holes drilled through? Or maybe you've seen plunger-shaped rings littered all over the beach on Steh-Chass inlet? They are not industrial waste! It turns out they are how female moon snails lay their eggs! We will share these findings with the children when next we meet, and bring some field guides along too.


For more moon snail facts, including how the snail's little 'door' works go to: The Washington Department of Ecology Critter of the Month blog post "We're over the moon for the moon snail."