I recently ate a pretty large soft-shelled crab, but when I opened the shell, there wasn’t much crab inside. Why is that?

For those who like to catch and eat boiled crabs, keep this in mind. A bigger shell after molting does not equate to a bigger crab inside. It's like buying shoes for kids: you buy them with room to grow. Same with the crab. You may have had the experience of cracking into a large crab to find little to eat inside. That was no doubt a crab that had recently molted. If you catch a crab with bright intense colors like it just came off the showroom floor, it probably did. You want what are called "rusties." They have brown algae growing on them and maybe a barnacle or two, that's a full crab.