Going to the beach this summer? One of the delights of summer is shell-hunting on the seashore. Learn about shells with your children as you hunt for these tiny treasures.
What is a shell? A shell is more than a pretty object that you find at the beach. It used to be an animal’s home. Many ocean animals have an organ called a mantle. This mantle concentrates calcium and forms calcium carbonate crystals. These crystals turn into a hard shell that grows as the animal grows. If you look closely at the edge of a shell, you will see the place where the shell is growing.
What sorts of animals have shells? Although people refer to many natural objects as shells, seashells come from molluscs. These include many common seaside and garden animals such as snails, clams, oysters, and mussels. These animals are very squishy inside, so they need a shell to protect their bodies. Some crabs wear the discarded shells of molluscs. These crabs are called hermit crabs, and their bodies have a soft part that is covered when they are inside a shell.
At the beach, investigate shells that have animals inside them. Place a mollusc shell in a tray of seawater and watch the animal gradually emerge from its shell. Then try to pick up the shell. Watch as the animal moves away from you using its muscular foot, or water as the shell closes. Be gentle with the animal and put it back when you have finished observing it.
If you are in an area that is not park land, your child may want to choose a shell as a feature of a necklace. Collect nature-inspired beads, then look for a shell that has a small, round hole. The creatures that lived in these shells were eaten by another animal that drilled a hole in the shell, likely a moon snail or Nautilus.
There are many nonfiction books that describe shells and their inhabitants, including my personal favourite series, the Eyewitness Books. There are also childrens’ stories that feature shells. Marianne Berkes’ book Seashells by the Seashore is a lovely description of a day at the beach. It follows a young girl as she collects seashells for her grandmother. For younger children, Is This a House for Hermit Crab by Megan McDonald is a wonderful story that asks children to consider appropriate habitats for aquatic animals. Hermit Crab needs a new shell and must find one that it just right for him.