By Brian Gilliland

DOVER — According to global wildlife tracking nonprofit OCEARCH, Marie, a 300-pound female loggerhead sea turtle tagged in Juno Beach Fla., in April 2024 as she laid eggs, has made her way steadily northward since, pinging off the Delaware coast on July 10, close to 6 a.m.

Marie was tagged as part of a long-term study understand how often a female loggerhead turtle is capable of producing a nest during a breeding season.

Since leaving Juno Beach, Marie has traveled more than 2,500 miles along the East Coast, according to her tracker, with about 70 miles coming in the last 24 hours.

Marie is a full adult, measuring 3.5 feet long, and weighing almost 300 pounds, which is about the average size for an adult of her species. Larger specimens have been observed weighing more than 1,000 pounds.

Loggerhead sea turtles spend most of their lives in the saltwater and estuaries of the Atlantic, Pacific and Indian oceans, as well as the Mediterranean Sea.

Loggerhead sea turtles have a generally low reproductive rate, with females like Marie reaching maturity between 17-33 years of age, then laying an average of four clutches, and then taking a few years off. The study Marie is a part of aims to understand this behavior more fully.

The average lifespan for a mature loggerhead is around 47-67 years without outside interference, though Marie’s age remains undisclosed, if known.

Young loggerheads and their eggs are vulnerable to predators, however when they reach Marie’s size, only large marine animals, like sharks are willing to risk the powerful jaws and thick hide of a sea turtle.

Marie, like other loggerhead sea turtles, is an omnivore and prefers bottom-dwelling invertebrates to eat.

Loggerheads are the world’s largest hard-shelled turtle, slightly larger than other sea turtles and the land-dwelling Galapagos tortoise, and second largest turtle after the leatherback sea turtle.

Gender differences in loggerhead turtles are only apparent in adult anatomy, with males having longer claws and tails, with shell differences presumably to accommodate the larger tail. Before adulthood, determining loggerhead sea turtle gender requires more involved testing.

Since its founding, OCEARCH has run 46 expeditions, and tracks more than 400 animals.