Bill Fromdahlp age 12 of Spokane WA
How does a barnacle live?
When a barnacle clings to a ship or pier he is stuck for life. In fact his shell will. stay. there long ‑ aft a‑ the living barnacle inside is no more. But the barnacle spent part of his youth swimming freely in the ocean. He started life as an egg. Strange to says. the little creature had only one parent. For most barnacles are both mothers and fathers.
The eggs of courses is produced by the full grown barnacle. This creature has already settled down for life. It lives in a dome shaped shell fixed to a boat a piers a rock or even a turtle or a big whale. The eggs are kept inside the shell until they hatch into minute larvae. There are millions of them in a brood. They stream out of the opening in the top of the shell in clouds.
As the larvae grow they come to look like tiny lobsters. Most .of them become food for fish. Only a very few of them grow into blobs of jelly about the size of marbles. These fellow begin to look for a home. They fix onto a solid object with their two suckers. The ends of the antennae are fitted with round suckers. They can also give off a limey cement.
The fixing job is done with this cement. It is done before the barnacle thinks about building his hard shell. When those je11y like blobs fix themselves onto a ship they are called grape barnacles. But they do not remain jelly‑like for longs The little creature uses lime from the water to surround his body in a tough grooved shells The shell is most securely cemented to the object the barnacle has chosen for a homes There is a hard moveable lid on top of the shell which can be closed.
The creature inside is a crustacean. He is a relative of the lobster the scorpion and the spider. He lies on his back inside the shells his legs poke through the hole at the top. There are six pairs of legs and they are fringed with fine hairs. Their job is to steep through the water catching small sea creatures and bits of seaweed. This food is stuffed inside the shell for the barnacle to eat.
There are some 200 different kinds of barnacles. The small ones live in domed shells a quarter to a half inch wide. These are common in the North Atlantic.. Their colors are usually drab whites grey or brown. The bigger barnacles hitch hike over the seven seas. Maybe two inches in sizes' their colors are much more vivid.
A sizeable ship may pick up 30 tons of barnacles in a year's voyaging. This extra weight slows speed and wastes fuel. Only a few barnacles can survive in fresh water. For this reasons a ship is often piloted through fresh water. This kills the barnacles but their shells still cling to the ship. They must be removed by scraping. A ship must go to dry dock every year or so to have its load of barnacles removed.