A terrapin is a type of turtle that lives in brackish water, which is the slightly salty mix of fresh water and ocean water found where rivers meet the sea. While sea turtles live in the ocean and most pond turtles stick to fresh water, terrapins thrive in marshes, estuaries, and coastal swamps along the Atlantic and Gulf coasts of North America.

The diamondback terrapin, with its patterned shell that looks like it's covered in geometric designs, is probably the most famous type. These medium-sized turtles have been around for millions of years, long before humans arrived in North America. They can hold their breath underwater for hours while hunting for snails, crabs, and small fish.

In the 1800s, people hunted terrapins so heavily for food that they nearly disappeared, but conservation efforts helped bring them back. Today, if you visit a salt marsh on the East Coast, you might spot a terrapin sunning itself on a log or paddling through shallow water with its webbed feet.