River Critters:
Crabs


Want a cool family getaway? Click Captain Walt's Charters.

A number of different crabs dwell along the bottom of the Bull river. The blue crab is the most abundant, but hardly the only species we find in our traps. Stone crabs and spider crabs often populate the area, too. But the blue crab is the most sought-after, and crabbing is the second largest fishing industry in Georgia, right behind shrimping.

Here are a few facts about the blue crab that you might find interesting. The fertilized female, or "sponge crab", produces about 2 million larvae. These tiny larvae are called a "zoea" (ZO-ee-ya). They go through a number of stages before they even look like a crab. As the tiny crab grows, it must shed its outer skeleton (exoskeleton), before it can grow. This process is called "molting". Several of the first few molts also involve a change of appearance. The "zoea" molt into the next crab form, called a "megalops". This larvae, resembling a small lobster, develops into an immature crab, or "first crab." It takes about two months from the time the egg is hatched to become a "first crab".

An immature female, or "she-crab", will molt a total of about eighteen to twenty-three times before reaching maturity. She will then cease to molt, after mating. Males have the same growth pattern, except that they do not cease growth after sexual maturity but continue to molt into the third summer. Since males continue to grow, a fully mature male crab will be larger in size than a mature female. Most female crabs attain full growth and mate only once, during their second summer.

Blue claws mean the crab is a male, (or "jimmy"). Red tips on the claws mean it's female. The sex is also determined by the differences in the shape of the abdomen, or "apron". The male apron is T-shaped. In the young immature female, it is triangular and sealed to the body. In the mature female, this apron is broadly rounded (almost semi-circular) and unsealed.

You might enjoy reading a children's story that I wrote for a young friend of mine. It's called, "Going through Changes, with Krilly the Crab".



Website written and hosted by Captain Walt's Charters