Range: Worldwide

Habitat: Brackish estuaries to deep waters

Size: Less than an inch (2.5cm) to over a foot (30.5cm) long

Diet: Worms, bivalves, fish and more

Threats: Crabs, sea turtles, sea stars, urchins, and fish

Lifespan: Up to forty years depending on the species

Transcript:

Today on Animal Fact Files we’re discussing whelks. While many different sea snails may be referred to as a “whelk” this video will focus specifically on the “true” whelks. Whelks are sea snails that live in marine waters throughout the world. Smaller species are also known from brackish water estuaries. These invertebrates live from sandy or muddy bottom areas to hard, rocky places, and they live from intertidal areas to more than 3,000 feet (914m) below the waves. Overall, there are more than 1,000 whelk species alive today. These snails have a spiral shell that can be squat or tall depending on the species. Those from the tropics are often smaller with more colorful, thicker shells while cold water whelks tend to be larger with thinner, duller shells. In size, they range from less than an inch (2.5cm) to over a foot (30.5cm) long!

Whelks have a squishy, spiral shaped body inside their shells. The part of their body that can be seen externally includes the foot, the operculum, the eye stalks, and the proboscis. The foot is used for locomotion. The shell covering, called an operculum, looks like a second shell connected to the foot. They also have eyestalks though they do not have complex eyes. Whelks have a long proboscis. This can extend to double the length of their entire body! The proboscis ends with radula, or teeth-like plates, which can spear or drill through prey. Whelks eat worms, bivalves, fish and more. Some drill through the shell of their bivalve prey while others use their foot to hold the animal in place and the mouth of their shell to pry the bivalve’s shell open! Whelks use their sense of smell to find food. Unlike cone snails, whelks don't use venom to subdue their prey. In turn, whelks are eaten by crabs, sea turtles, sea stars, urchins, and fish.

If you've been to the beach, it's possible you've seen the egg case of a whelk. They can appear as long, tendrilly things or clusters, and they were supposedly used by sailors as a type of hand soap! Whelks are separated into males and females. They mate with internal fertilization and the female lays an egg case containing upwards of 2,000 eggs. She'll lay multiple of these during a season. In some areas, these can litter the seafloor for miles! Only about one percent of the eggs hatch from their capsules. The others are used as a food source for the newly hatched young. When they emerge, baby whelks look like much smaller versions of the adults. Whelks can live to be 40 years old and when they die, their empty shells may be used by hermit crabs as a new house.

For more facts on whelks, check out the links below. Give a thumbs up if you learned something new today. Thank you to our Patrons SpikeSpiegel93, Dad, and everyone else for their support of this channel! And thank you for watching Animal Fact Files!