Several summers ago I spent three days on a barrier island where loggerhead turtles were laying their eggs. One night while the tide was out, I watched a huge female heave herself up on the beach to dig her nest and empty her eggs into it. Afraid of disturbing her, I left before she had finished. The next morning I returned to see if I could find the spot where her eggs lay hidden in the sand. What I found were her tracks leading in the wrong direction. Instead of heading back out to sea, she had wandered into the dunes, which were already as hot as asphalt in the morning sun.

A little ways inland I found her: Exhausted, all but baked, her head and flippers caked with dried sand. Af…