Earlier this year, the Western Pacific leatherback (Dermochelys coriacea) left a nesting site in the Solomon Islands and dove 4,409 feet (1,344 meters) beneath the ocean surface, according to the environmental organization The Nature Conservancy.
At that depth, the leatherback swam deeper than the current Guinness World Record for the deepest turtle dive — 4,199 feet (1,280 m) — set by another leatherback, the deepest-diving reptile species. For context, Navy submarines have reportedly gone to depths of around 2,950 feet (900 m), while the deepest human scuba dive was 1,090 feet (332 m).
