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. In areas where recreational boating and ship traffic is intense propeller and collision injuries are not uncommon.
Sea turtles are at risk when encountering an oil spill.
Respiration, skin, blood chemistry and salt gland functions are affected. Pesticides, heavy metals and PCB's have been detected in turtles and eggs, but the effect on them is unknown. Marina and dock development can cause foraging habitat to be destroyed or damaged. Turtles have been caught in saltwater intake systems of coastal power plants. Underwater explosions can kill or injure turtles, and may destroy or damage habitat.