When the water temperature drops below about 68 degrees, activity rates plummet and growth ceases. Lightning whelks grow to a length of inches and are sometimes mistaken for conchs. They live in shallow water and prefer embayments having sandy or muddy bottoms. Prime habitat includes estuaries, creeks and oyster bars. That's where this carnivorous species finds its food, which includes some scavenged carrion, but consists mostly of marine bivalves.
Busycon contrarium especially likes clams. An adult lightning whelk eats about one clam a month, and it's not very picky about the type. In areas where whelks are plentiful and take a significant toll on edible clams, shellfishermen consider them a nuisance.
Whelks themselves are edible, but even though they are a popular food in some areas of northern Europe, few Americans eat them. This is not to say that the Busycon contrarium has no fans.
Collectors and casual beachcombers admire the lovely shell and its unusual sinistral whorl. Whether you like lightning whelks or not, you have to admit that they are highly skilled clam killers. To detect prey, the whelk turns its long inhalant siphon in the direction of the current. The process is analogous to a wolf turning his nose into the wind and sniffing for prey that's out of sight. After a whelk detects a clam, moves to it, and makes contact, the clam hasn't got a chance.
The whelk, which is marvelously equipped to get the job done, uses a technique that is simple but brutally efficient. Employing its large, muscular foot see photo to pry open the clam's shell, it then uses the flaring lip of its own shell to wedge the clam shell open while it inserts its radula and proboscis to loosen and remove the soft tissue inside.
The next time you find an empty lightning whelk shell on the beach and admire its beautiful sculpture, you might want to give a thought to the ingenious way this creature gets its food. Whatever else it may be, the lightning whelk sure is hell on clams.
If you know what to look for while beachcombing, you can also find lightning whelk egg capsules. In late spring or early summer, female whelks lay egg capsules in strings attached to the sandy bottom.
Each little disk-shaped capsule in the string contains numerous baby whelks protoconchs. If all goes as intended, the capsules later break loose from the string. However, many egg capsule strings break loose, wash ashore, and dry out.
These desiccated strings, which are sometimes called "mermaid's necklaces," are brittle and feel like hard plastic. You can see one at this site. Postscript : How heavily the Deepwater Horizon oil spill will impact lightning whelks along the Gulf Coast remains to be seen, but the outlook appears to be bleak in areas that are oiled in amounts sufficient to seriously disrupt the food chain on which the whelks depend. Something alot of people might not know about the whelk is that is was extensively used by early Native Americans for food and also for tool and ornament making.
They sometimes even eat other whelks. Whelks are pretty keen hunters. They can use their radula a tongue-like organ for feeding to drill a hole into the shell of their prey. Lightning Whelks reportedly played a significant role in Native American cultures, because their left-side opening means their shell spirals clockwise rather than anti-clockwise. This is thought to signify light to darkness and birth to death in native beliefs, and the shells were used in both daily life and spiritual rituals.
Many whelk shells have been found at ancient burial sites: the oldest was in Kentucky, and dates back some 5, to 6, years. These days, a lot of people still love collecting the beautiful whelk shells.
So what to do if you find one while wandering on a Florida beach? If so, leave the creature in its habitat. Occasionally another strange whelk-related object shows up on the beach — like this one, found recently on Seagrove Beach by two Volunteer Beach Ambassadors.
Whelks lay their eggs in a long, spiral-shaped casing that can reach up to 33 inches in length. Knobbed whelks are marine gastropods that live in tidal estuaries along the Atlantic coast. Their spiral shells can range in color from grayish white to tan.
The whorled or spiral shell of the knobbed whelk has low knobs or spines on its shoulder, and the shell opening is located on the right side. The shell color varies over geographic locations: the outer shell ranges from grayish white to tan, while the inner shell ranges from pale yellow to orange. A hard plate called the operculum acts like a trap door when the snail retracts into its shell.
The body of the snail is divided into head, abdomen and foot. Two pairs of tentacles are located on its head: one senses light, while the other is used for touch and smell. Adult knobbed whelks measure five to nine inches in length.
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