For Crabby Girls, Bigger is Better

Effects of crab sex life on Maryland industry

It's nearly Valentine's Day. And for humans, love is in the air. But it's a good time to examine how love is in the air for crabs, too, and how their mating affects a Maryland industry.

For blue crabs, it's all about the pheromones in the water. And for female crabs looking for mates, size really does matter.

Sook Chung, an associate professor at the Institute of Marine and Environmental Technology at the University of Maryland Center for Environmental Science, explains that a larger male may produce more sperm, and that's critical to the female, who gets just one chance to mate.

"That's it -- just once," says Chung, who adds it's important female crabs find a large male who can produce lots of sperm to fertilize her eggs, ensuring that she can produce as many tiny crabs as possible.

And of course, having a 5.25 inch minimum size on male crabs guarantees that very few male crabs get much much bigger than that.  Putting a 6 inch limit would probably allow Jimmies one more molt, and a little more time to mate before being cooked.

For bonus points, a "sook" is a female crab in the Chesapeake parlance:

Chung didn't start her career by focusing on marine life. She originally studied insects, but made the change to marine studies after discussions with colleagues. And she found a connection with the blue crab: She's a native of South Korea and her first name is Sook. When she came to Maryland to study crabs, she learned that watermen call male crabs "Jimmies" and females "Sooks."

It's a coincidence that amuses her.