Seeing as some species don't reach sexual maturity for 50 years, an 80 year lifespan seems reasonable. Turtle age is determined by the growth rings of the scales on a turtle's back. Scientists count these rings and use a mathematical formula to determine age. Unfortunately, most sea turtles never reach maturity because of human impacts on their lives. The impacts include the destruction of turtle nesting ground for development, poaching of eggs and adults for food, death by ingesting garbage or becoming entangled in fishing nets and line, or six-pack holders.
Thousands drown in shrimp nets, and some die from collisions with boats.
Human disturbances such as trash or bright lights on a nesting beach can cause a female to return to the ocean without laying her eggs. Babies, once they hatch, may become disoriented by city and street lights. These reasons are why all the sea turtles found in US waters are on the endangered species list. A. Scientists recognise 8 different species of sea turtles in the world. They generally live in tropical seas, and come up on sandy beaches to lay their eggs.