Treasures of the sea

During our visit to the sand dunes, my youngest daughter, Esmee, collected some shells. Shell collecting is a a wonderful nature activity. Children love shells. They are fascinated by their shape, their texture and even the sound they hear when they hold a shell to their ear. What is even more interesting is that these beautiful treasures are a creature's habitat.

Shells are made by mollusks - animals with soft bodies and no bones. They build shells on the outside of their bodies, to protect them and keep them safe inside. These exoskeletons are important to these creatures, as they provide them with shape and rigidity, protection, and sometimes camouflage, from predators. The shells are made from calcium derived from the environment, through their food or the water they live in.

The mollusk lives in the same shell, making it bigger as they get older. Each different species of mollusk makes a shell that is, in most cases, unique to it alone. The empty shell your child finds on the beach is a discarded shell of a mollusk that has died and has washed up on the beach by the incoming waves. Your child is not causing any harm to an animal when they pick up an empty shell. Esmee found a shell which still had a living mollusk in it as saw it moving inside. She placed it back in the water. A living mollusk should be left where it was found.

Conchologists are people who study shells. They also study the animal who made the shell -- their anatomy, their life history and their habitats. The study of mollusk is called malacology. Mollusks are classified into major groupings according to the characteristics of their shells. The phylum Mollusca includes organisms such as clams, snails, slugs, octopuses, squid, and chitons. There are many guides and books available, dedicated to the study of shells. For New Zealand shell collectors, The New Zealand Mollusca website is a terrific website, with great photos, for identifying your shells. Esmee and I discovered that we found several different shells; scallop shells, clam shells, helmet shells, paua shells, spiral shells and valve shells. We found one shell we haven't been able to identify. If you know the name of this shell, please leave a comment.

Esmee had a wonderful time walking the beach and collecting shells. Young children see beauty in every single shell and are as excited about the next one they find buried in the sand as the one they found before. This may result in a big pile of shells, which your child may insist on taking home. Spent some time with your child, looking for the largest, smallest, prettiest shell and, as a compromise, only take these home, and leave the rest. Although the main treat to our marine friends is habitat destruction, by only taking a limited number of shells, you will teach your child respect and moderation, while still enjoying the wonderful treasures of the sea.

Did you know? Collecting and studying shells and their makers, the mollusks, is one of the oldest natural history pursuits of man, dating back to the Romans and before -- indeed, a shell collection was preserved in the ruins of Pompeii. Aristotle, and then Pliny the Elder were among the first naturalists to write about shells and their peculiar anatomies; in fact it was Aristotle who coined the name "Mollusca," meaning "soft-bodied." Source: The Conchologists of America website