A heavy-headed turtle with jaws built to crush shellfish, so the head looks large for the animal.
Shell about 90 cm in a typical adult and up to 110 or 120 cm in a large one, and 90 to 160 kg. Much larger historical figures are quoted but are not substantiated and should be treated with suspicion. The head is very large, broad and blocky with powerful jaws, and looks oversized for the animal; that is the most reliable field mark. The shell is reddish-brown to yellow-orange and often carries a heavy load of barnacles.
Count the costal scutes. The loggerhead has five pairs; the green turtle and the hawksbill have four. The hawksbill also has a narrow pointed beak and overlapping scutes, which the loggerhead does not.
It crushes conch, whelk, crab and urchin with its jaws, so divers often find it working the substrate, and it rests motionless on the bottom or wedged under a ledge, largely indifferent to being watched. It is the most approachable turtle on this site. It is submerged up to 85 per cent of the day, with routine dives of fifteen to thirty minutes and resting dives that have exceeded ten hours in cool water.
The global listing of vulnerable is not much use for this species. The IUCN assesses ten separate populations and they run the whole range. Florida, Bahamas and Cayman animals belong to the northwest Atlantic population, which is of least concern. Eastern Australian animals belong to the south Pacific population, which is critically endangered. Same species, opposite ends of the scale. It is protected in every country on this site.
Ratings are per location: 1 means found on most dives that look for it, 5 means a handful of records. Where enough dives have been logged the figure is calculated from them; otherwise it is an editorial estimate, and says so. We publish habitat and destination, not the dive site.