We found a long, coiled string of little “packets” on the beach. It was kind of white, and each packet was about the size of a quarter. Any idea what it was?

April 2007

Female whelks create an off-white egg case consisting of many chambers that contain hundreds of eggs. (Photo by Paul Dunn)

Female whelks create an off-white egg case consisting of many chambers that contain hundreds of eggs. (Photo by Paul Dunn)

Your good description identifies your find as the parchment-like egg case of a whelk. This odd-shaped, linked capsule is also called “mermaid’s necklace.”

Whelks are single-shelled sea snails. Females may lay several strings of eggs over a period of days, and each string can consist of more than 100 chambers or “packets.” The cases can measure up to 2 feet long and chambers can contain 20 to 100 eggs each.

Initially, the female attaches the egg case to a shell or rock, or buries one end in subtidal sand. The eggs hatch inside each chamber, where they feed on their unhatched siblings. After about two weeks, tiny whelks chew their way out of the chamber to begin life in the sea. Some egg cases, especially empty ones, become dislodged by storms or strong currents & wash up on beaches.

Each whelk hatchling emerges as an exact replica of its parents – shell and all. Occasionally, chambers can be found with a few small whelks still inside. Most often, though, all that is left is a round hole in the chamber where the young made their getaway.

Whelks grow quite large. An unblemished shell is highly prized by beachcombers. Along North Carolina beaches, whelks are commonly called conchs, however, true conchs are found in warmer waters farther south.