step on the barnacles!
make a good 'first station' to sensitise visitors to the fact that
every inch of the rocky shore is alive.
are often mistaken for snails because of their hard 'shells'. However,
barnacles as actually crustaceans, and their close relatives include
crabs and shrimps!
Young barnacles are shrimp-like and swim freely. Eventually, they
glue themselves head down onto a hard surface and develop the shell.
A closer look at barnacles
barnacle is alive and which one is dead? A barnacle shell
has a little hole where the animal sticks its feathery feet to
feed with. Living barnacles need to stay wet. At low tide, they
shut the hole in the shell with a 'door' so that they don't dry
out. A shell without a door is an empty shell, and the barnacle
has died. But sometimes, there are other small animals that might
live in the empty shell (e.g., tiny periwinkles).
are the barnacles all crowded together? "Why are
these no barnacles higher up on the rock here?" "How
many different kinds of barnacles can you find and where are they
found?" This is a good chance to explain tides
it a limpet or a barnacle? Here's more on how
to tell them apart.
are important to the ecosystem
is this ugly looking snail on the barnacle? Yes, it's
Although barnacles have thick shells, they don't move. So they
are easy food for snails and animals that can get through their
shells. And this snail has a special way to get to the shell.
- Many other
animals love to eat barnacles!
They are an important part of the ecosystem. Can
we think of some animals that might eat a barnacle? Some
charismatic animals to highlight: crabs.
affect the price of your imported goods!
also have useful applications e.g., super strong glues
that work in seawater, and very hot and very cold conditions.
myths to dispel
luak' or oyster omelette is not made from barnacles. They
are made from oysters.
barnacles: Almost every hard surface that is submerged in
seawater at mid-water mark and below will have barnacles.
Do NOT crack open barnacles or scrape them off. Visitors
will do as we do and not as we say. Use a guidebook to show
the internal structures of a barnacle. Sometimes, dead barnacles
shells are washed up on the shore. You can use those to explain
Choose a long 'wall' of barnacles when talking about
them, so that the group can spread out and each person can look
at a piece of wall.