The Amelia Current

Fort Clinch is a 19th-century masonry coastal fortification, built as part of the Third System of seacoast defense conceived by the United States. It is located on a peninsula near the northernmost point of Amelia Island in Nassau County, Florida. The fort lies to the northeast of Fernandina Beach at the entrance to the Cumberland Sound, in the northeast part of the state. Today it is included within the boundaries of Fort Clinch State Park. This site was first fortified in 1736 by the Spanish, when they held colonies in Florida. From 1736, various nations to control the territory have garrisoned and fortified this site to protect the entrance to the St. Marys River and Cumberland Sound. After the end of the Second Seminole War, the United States started construction of a fort, later named Fort Clinch, in 1847. It was part of its Third System of coastal defenses conceived earlier in the century, which guided fortifications throughout this period.

Mating and egg laying occur during the spring and fall migration. Internally fertilized eggs are surrounded by a transparent mass of albumen, a gel-like material, and are laid in protective flat, rounded egg capsules joined to form a paper-like chain of egg cases, commonly called a "Mermaid's Necklace". On average each capsule contains 0–99 eggs, with most strings having 40–160 capsules. After laying their egg cases, female knobbed whelk will bury one end of the egg case into the substrate, thus providing an anchor for the developing fertilized eggs and preventing the string of egg cases from washing ashore where it would dehydrate. Fertilized eggs develop in the capsules. Young emerge with a shell approximately 2–4 mm in length. Young are preyed upon by crustaceans, horseshoe crabs, and fish, primarily drum species. Adult whelks are eaten by loggerhead sea turtles. As with conchs, the knobbed whelk is used by humans as food in such dishes as salads (raw), burgers, fritters, and chowders.