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This blue crayfish just molted. It is larger than its old shell.
How Do Crayfish Grow?
Crayfish are completely covered by a hard shell. The shell cannot grow.
So how does a crayfish that is less than 1 centimeter (cm) long get to be
10 cm long? The crayfish
molts
.
During molting, the shell splits between the carapace and the tail.
Then, with a couple of flips and shakes, the crayfish slides out of its
old shell. The crayfish comes out with its new shell already on. But it
is soft and flexible. This is when the crayfish grows. Within minutes, it
expands. The crayfish is much larger than it was before it molted.
It is important for the freshly molted crayfish to stay hidden. It cannot
defend itself or find food when its shell is soft. In 2 days the shell will
once again be hard and strong.
A crayfish will molt 6 to 8 times during its life. It may molt 5 times in
the first 2 months of life. This is when the crayfish is growing fastest.
After its first year, it will molt less often because it is not growing as fast.
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