Let’s learn about these extraordinary creatures, the lightning whelk. But before we do that, let’s quickly review a bivalve and a gastropod.
A gastropod is a mollusk, such as a snail or slug or whelk. It only has one piece to it’s shell.
A bivalve is a mollusk that has a compressed body enclosed within a hinged shell, such as oysters, clams, mussels and scallops. In other words, the critter is enclosed by two halves of it’s shell.
That black part of the critter is the foot and that oval shaped piece that will cover the snails body is called the operculum.
The lightning whelk is a gastropod mollusk and almost always left-handed - also known as a sinistral shell. A sinistral shell means the shell is coiled in an anti-clockwise direction, so when viewed from the front, the opening or “aperture” appears on the left. The concept of sinistral shells have fascinated countless shell collectors over the years. Just as the majority of humans are right-handed, gastropod mollusks follow a similar trend and a left-handed shell is somewhat of an oddity.
The largest sinistral mollusk is – you guessed it – the lightning whelk.
Lightning whelk begin as hatchlings. They come from an egg casing that looks like this:
There are tiny thinner pieces of each of the layers of the egg casing and the little ones manage to slither out. The whelks that hatch will feed on the eggs that did not hatch. That can be considered either quite convenience or quite gross – I’ll go ahead and let you be the judge. The little snails will continue to grow and their shell grows with them.
I have read quite a few differing statistics on how big these guys get, but they seem to max out around 15-16.” Here is an example of one that is almost that big. This was the biggest one we’ve found so far. My husband needed two hands to safely handle this guy.
I could not get a reliable number as to how old these guys can get. On one site it says 10-20 years to reach 8”, so it’s a bit of a mystery how long these critters can actually live.
Lightning whelks are predatory and they eat bivalves. Remember, a bivalve is a critter that has 2 shells. The larger whelks will insert the edge of it’s shell inside the bivalve and use it like a crowbar. It if cannot pry the bivalve’s shell open this way, it will grind the shell with it’s own shell until it creates a hole large enough to insert it’s radula or toothed tongue in. The lightning whelk can “smell” its prey with special sensory organs inside it’s body and will almost completely bury itself searching for other food. We happened to find this lightning whelk eating a clam.
Native Americans harvested whelks for food, religious ceremonies and practical tools. Many tribes believed that the "left handed" spiral made the shells sacred objects, but whelks were also eaten and their shells used as scrapers, gouges and even cups and bowls. There is a house on Fort Myers Beach called the Mound House. If you’d like to see how shells were used by the Calusa Indians, make sure you stop over and check it out. I don’t want to spoil the best part, but they have a underground exhibit where you can see layer upon layer of shells. The picture below does it no justice – you should check it out for yourself.
The lightning whelk is the official state shell of Texas and is an all-around neat critter and shell. I hope the next time you find one, you'll remember at least a few interesting facts about these fascinating gastropods.