Short answers, pulled from the story.
There are seven living species of sea turtle: the flatback, green, hawksbill, leatherback, loggerhead, Kemp's ridley, and olive ridley. Five of the seven are listed as threatened with extinction on the IUCN Red List.
The leatherback is the largest sea turtle, reaching 1.4 to more than 1.8 m in length and weighing between 300 and 640 kg. The smallest is the Kemp's ridley, which can be as little as 60 cm long.
Sea turtles navigate using magnetoreception, relying on both a bicoordinate magnetic map and a magnetic compass sense. The map fixes their position using magnetic parameters such as field intensity and inclination angle, while the compass sense lets them hold a steady heading.
A nesting female hauls onto the beach, almost always at night, and uses her hind flippers to dig a circular hole 40 to 50 cm deep. She lays a clutch of 50 to 350 soft-shelled eggs depending on species, then refills and camouflages the nest before returning to the sea.
A foraging sea turtle typically spends 5 to 40 minutes underwater, while a sleeping sea turtle can remain submerged for 4 to 7 hours. When forcibly submerged in something like a trawl net, its diving endurance drops sharply and it is more likely to drown.
Sea turtles face threats including bycatch from imprecise fishing such as long-lining, the black-market trade in eggs and meat, light pollution that misleads hatchlings, plastic debris mistaken for jellyfish, and oil pollution affecting every life stage. The IUCN Red List rates two species as critically endangered and three as vulnerable.
Diet varies by species. Green sea turtles become exclusively herbivorous as adults, leatherbacks feed almost entirely on jellyfish, and hawksbills specialize in sponges, which make up 70 to 95 percent of their Caribbean diet. The loggerhead, Kemp's ridley, olive ridley, and hawksbill are omnivorous, eating animals such as decapods, mollusks, worms, and fish.