The young turtle has been swimming for three months now in the same warm shallow bay, dreaming of calm water and plenty of food. But as the days begin to shorten and the night comes earlier and earlier, the water grows colder. It drops to fifty degrees Fahrenheit . Swimming is harder. Its heartbeat slows--and almost stops. The young turtle is in danger of losing its life. Ten days before Thanksgiving, Max Nolan, a ten-year-old boy, and his mother begin their _ . The Nolans are among volunteers who walk Cape Cod's beaches during November and December to search for turtles who are often cold and trapped and seem dead--turtles whose lives they may be able to save. Max and his mother and the other volunteers do an important job. All sea turtles are threatened or endangered. Among them Kemp's ridleys are the most endangered. Right now on our planet there are fewer than eight thousand Kemp's ridley turtles left. Max is far in front of his mother when he sees a turtle washed up by the surf. He runs up to it and shouts to his mom, "Got one!" The turtle is cold. Its eyes are open, but the turtle is not moving at all. It might be dead or still alive. Max remembers the instructions given to all the volunteers. He picks up the turtle, which weighs about five pounds, and moves it above the high-tide mark to keep it from washing out to sea. Then he runs to find seaweed to protect it from the wind. He finds a stick to mark where it is, and next, he and his mother go to the nearest telephone and call the sea-turtle hot line for help. The young turtle is in danger of losing its life because   _  .
it has been swimming for three months it dreams of calm water and plenty of food the water drops to fifty degrees Fahrenheit the days get longer and the nights come earlier