Trees shading a beach can also change nest temperatures, altering the natural sex ratio of the hatchlings. The use of hopper dredges can also kill turtles caught in dragheads. Loggerhead turtles eat a wide variety of marine debris such as plastic bags, plastic and styrofoam pieces, tar balls, balloons and raw plastic pellets. Effects of consumption include interference in metabolism or gut function, even at low levels of ingestion, as well as absorption of toxic byproducts. NMFS is currently analyzing stranding data and available necropsy information to determine the magnitude of debris ingestion and entanglement.
Most turtles killed are juveniles and sub-adults.
Inshore catch and mortality for shrimp trawlers is not known, but is thought to be significant. Bluefish, croaker and flounder trawl fishing are also a serious threat. Turtles are taken by gillnet fisheries in the Atlantic and Gulf of Mexico, but the number is currently not known. Several thousand vessels are involved in hook and line fishing for various coastal species. The capturing of turtles is not uncommon, but the number is currently not known.