Loggerhead Turtle

The loggerhead sea turtle (Caretta caretta) is the world's largest hard-shelled sea turtle, named for its disproportionately large head, which houses powerful jaw muscles capable of crushing the hard-shelled prey it favors. Adults typically weigh between 155 and 375 pounds and measure around 3 feet in carapace length, according to NOAA Fisheries. They are highly migratory, ranging across the Atlantic, Pacific, and Indian Oceans, with females making remarkable transoceanic journeys to return to the beaches where they hatched in order to nest.

Loggerheads play a measurable role in marine food webs: by preying on benthic invertebrates such as horseshoe crabs, whelks, and sponges, they help regulate populations of organisms that would otherwise dominate those communities. The IUCN Red List classifies the species as Vulnerable globally, though some subpopulations are listed as Endangered or Critically Endangered. Bycatch in longline and trawl fisheries is the most significant driver of adult mortality worldwide, compounded by coastal development that degrades nesting beaches, artificial lighting that disorients hatchlings, and the increasing effects of climate change on sand temperatures, which influence hatchling sex ratios.