Diamondback Terrapins

Each year, just as people are heading for the beaches, so are the female Diamondback terrapins. The terrapin lives in the Delaware Inland Bays, but the females lay their eggs in the soft sands of the beach dunes, and mid-May to mid-July is their nesting season.

Some are killed crossing Coastal Highway. Unfortunately, nearly all the terrapins that are killed are adult females. Because they can live for 25-30 years and can continue to reproduce for two decades, every female lost is also a loss of all her potential offspring. One solution is more sandy beach habitat on the Bays. But, these are becoming rarer and rarer as shorelines are hardened with bulkheads and stone. As an alternative to bulkheads and stone, the Center recommends installing a “living shoreline” that can reduce wave energy, trap sediment, and filter runoff, while maintaining (or increasing) beach or wetland habitat. Such habitat can protect Diamondback terrapin populations by providing areas for feeding and growth.

Terrapins Monitoring

Diamondback terrapins are an important salt marsh predator and are an iconic species for the region. Little is known about their long term population status, and how that changes year to year and place to place. Terrapins also face a number of serious threats including habitat loss and collisions with motor vehicles. To answer questions about terrapin population status, and ultimately to help with conservation efforts to increase terrapin numbers the Center is beginning a citizen science-based survey to count terrapins annually at multiple locations throughout the bays.

What’s it like to do a Survey?

Volunteers can perform surveys by kayaking a predetermined route (performed in pairs with another volunteer) or counting from a chosen land-based location. The survey can occur anytime from the last week of May through the second week of June but must be performed when weather conditions meet specific criteria for wind, cloud coverage, air temperature, and tide. All paddling routes are less than three miles round trip. Volunteers performing the paddling surveys must have their own kayaks and be comfortable paddling the chosen route without a guide. Observers will count the terrapin heads they see while performing the survey, and provide a GPS point for each terrapin (phone GPS points are accepted). Volunteers must attend training in order to participate in the survey.

Volunteers Needed for this Survey!

If you would like to participate in the survey, contact environment@inlandbays.org Even if the survey is not currently underway, you will be added to the mailing list and receive information prior to the survey season. The season kicks off in April of each year, then runs from May to June.  This survey is weather dependant and it does not have a set schedule with possible last-minute notices to participants.

*You will need to fill out a Liability Waiver for each individual or family member participating and submitted it prior to your survey day. Individuals under the age of 18 must have an adult chaperone on-hand at all times.

Terrapins Garden (Coming Soon!)

The Center is preparing to install a turtle garden for nesting Diamondback terrapins that will be located in Delaware Seashore State Park. The nesting site will provide a suitable habitat that will allow female terrapins to lay their eggs. The background of this project came from the understanding that suitable nesting habitats are difficult for terrapins to locate due to habitat loss and limited accessibility. Efforts have already been made in Delaware to bring attention to this species and implement ways to help limit roadway fatality. In addition, this project will serve as an educational site for the general public to learn about the importance of this species and its role in the Inland Bays ecosystem. There has been reported success of this same project in New Jersey and we expect the same result in Delaware.

In the meantime, check out this cool article on
Terrapins featured in our Summer 2019 Inland Bays Journal!