The Diamondback Terrapin

By Terri Estes

Diamondback terrapins, or simply terrapins, owe their name to the diamond-like rings on the plates of their shell. Each ring pattern is unique to them, just like our fingerprints are to us. Females tend to be larger than males, with their shells growing up to nine inches, while males grow to an average of five to six inches.

There are sea turtles that live in salt water and aquatic turtles that live in fresh water. The terrapin is the only turtle that lives in brackish (a mixture of sea water and fresh water) waters. The salt/freshwater estuaries and tidal marshes that are common in the inlets and coves of Jamaica Bay are perfect dwellings and breeding grounds for this turtle. Their main domain is in these brackish waters, but they are able to venture into salt water and fresh waters for periods of time. This turtle can be found from Florida to Cape Cod, Massachusetts, but Jamaica Bay is home to the largest known population of terrapins in the whole Northeast.

The population of the terrapin has declined in Jamaica Bay by more than half in the last decade. The reason for the decline is unclear, but there is an ongoing study to find the reason for their demise. The terrapin plays a crucial role in the health and resiliency of Jamaica Bay’s ecosystem. These turtles feed heavily on periwinkle snails, that would otherwise decimate the grasses that make up the bulk of these marshes. Ecologists consider the terrapin to be a keystone species in the bay. Without them, the delicate ecosystem would spiral out of balance.

These turtles can live for 45 to 50 years in the wild. Several years ago, a very good friend of mine was walking home after parking her car in Breezy Point. She came upon a tiny, quarter sized turtle lying in the middle of the sidewalk. We surmised that it must have been dropped by a shore bird that had picked it up after it hatched. My friend brought the tiny turtle home and called the NY Aquarium to ask what kind of turtle she had, and what she should do. They informed her that she had a diamondback terrapin baby and that it was illegal to keep them. They also informed her that if she released the baby turtle, more than likely, it would not survive. Naturally, she kept it. Her turtle is now more than six years old. It lives in a giant tank and is quite happy. Now, I am not for keeping wild animals as pets, but this little guy would have been a goner if my friend didn’t rescue and keep him. Since they live for such a long time, I’m guessing that the turtle will be left to some lucky relative in her will.

Let’s hope that the diamondback makes a comeback in Jamaica Bay. Our waters and ecosystem depend on them!