Recently, while scanning the beach on Sanibel, we tend to see one particular ‘ocean debris’ that spikes curiosity in the minds of beach-goers. Is it some kind of snake? Is it man-made? Is it even a part of this planet? After big winds, mysterious capsules of all shapes and sizes wash up on our shores. We'd like to share a little bit about these cases and what comes out of them!
The lightning whelk is a common sea snail here on Sanibel but has a shell that is not typical of most shells - it actually spirals and opens to the left side instead of the right, so we call it a left-handed shell. Covering its spiraled shell are vivid lightning-like markings that give this snail its name. Other than having a beautiful shell, it also lays the famous long snake-like egg clusters that we find washed ashore. The spiraled cluster of small disc-like pods can be over a couple feet long and it is the most common egg case washed up in the wrack line on Sanibel.
The pear whelk is a medium-sized shell and is not as common as the other snails we often see in this area. This smooth shell lacks horns like the lightning whelk and is not as colorful. These snails also lay long snake-like chains of egg capsules that are very similar to the lightning whelk. If you happen to be lucky enough to find these egg cases, compare the size with the lightning whelk egg cases - the pear whelk cases are much smaller in size, which includes the disc diameter and the length of the chain. The discs also have many projections along their margins - another key characteristic.
Florida Horse Conch
The Florida horse conch is the state shell of Florida and one of the largest snails in the Gulf. Surprisingly, the massive shell often covered with algae, is not the first thing most people notice but rather, the bright orange soft body of the animal. Female conchs deposit egg cases that resemble a cluster of yellow flowers on hard objects on the ocean floor, such as rocks and shell debris. These egg cases can sometimes be confused with the banded tulip snail egg cases, but horse conch egg cases have 4-6 rings that run along the length of each individual capsule.
Banded Tulip Snail
The banded tulip is a brightly colored, medium-sized shell that is named for its resemblance to a tulip flower blossoming. Much like the horse conch, the female tulip snail lays its eggs on hard-submerged objects. The egg cases also resemble a bouquet of small yellow flowers but differ from the horse conch cases because they are smaller and lack the rings on each individual capsule. You might even find these eggs laid on other snail egg cases, which is another clue that they are tulip eggs!
Now it's time to get out to the beach and explore - next time you're at the beach, see if you can identify any egg cases that you find! Happy beachcombing!