There are many threats to sea turtles, but most of them come from humans. Dangers may range from getting entangled in fishing gear to losing their habitats from beach erosion and human development.

Some Midwesterners dream of trading winter for warmth by moving to Florida to start a new life. For Nickel, the green sea turtle in the 90,000-gallon Caribbean Reef exhibit at the Shedd Aquarium, the ...