EVERYDAY SCIENCE

Detailed explanation-1: -Sponge Crabs are egg bearing female Blue Crabs. The females are only able to mate when the are soft after shedding. Once impregnated, a ‘sponge’ of eggs will begin to grow out of the apron on the underside of the crab.

Detailed explanation-2: -Mature females (Sooks) have a rounded apron as in the second picture below. You may also see crabs with triangle-shaped aprons. These are immature females and are called “v-bottoms”.

Detailed explanation-3: -A female red crab can lay up to 100, 000 eggs, which she holds in her abdominal sac. With the arrival of the waning moon, females make their way into the sea. In what looks like a dance, females brace themselves at the waters edge, and release their eggs.

Detailed explanation-4: -Male blue crabs have a “T” shaped apron while mature females have a dark “U” shaped apron and immature females have a slight “V” shaped apron. Female blue crabs carry eggs in masses under their abdomen. These masses are bright orange and spongy. At this point, the female is called a “sponge crab.”

Detailed explanation-5: -Eggs are fertilized as they pass out of the crab’s body and are deposited under the apron. The apron is actually the curled-under abdomen, and has small appendages to which the eggs attach. Egg masses have an average of two million eggs, and can have up to eight million eggs.