Blue crabs are fascinating animals with tons of cool adaptations. Here are four things the Sea Squirts learned about blue crabs today.
1. Male and female crabs have different markings on their abdomens.
Male blue crabs are a tasty snack for many humans, so knowing how to tell the difference between a male and female crab is a handy trick. Male crabs, or "Jimmies," have a Washington Monument shape on their underside, while Female crabs, or "she-crabs," have a capitol building shape instead. For every crab the Sea Squirts caught, they checked the abdomens to tell which was which.
2. Blue crabs can swim through the water.
Although they prefer to live on the seabed, blue crabs are one of the few types of crabs that can swim. Their back legs -- which look like flippers -- are called swimmerets, and they let the crabs move through the water with ease. Sea Squirts looked on as the camp counselors held the crabs by the joints on their swimmerets to avoid a pinch from the crabs' nasty claws. However, you can also hold a blue crab by its claws as well. Just be careful because…
3. Blue crabs can lose their claws.
Humans aren't the only animal that enjoys feasting on a blue crab. Many types of predators find them tasty. One adaptation blue crabs have is being able to lose their claws in a pinch so that they can swim away from whatever is trying to eat them. One of the Sea Squirts actually caught a crab that had lost its claw. Believe it or not, these claws can grow back! And it happens because…
4. Blue crabs molt.
Crabs have hard exoskeletons. As the crabs grow bigger, they have to shed their exoskeleton about once a month so that they can continue to fit inside it. This process is called molting. When this happens, the crab slowly regrows its missing limbs. The Sea Squirts found a "dirty" blue crab, which had algae growing on its exoskeleton. This means that it had been a while since it had molted, and it probably would do so soon!