Turtles at Colonial National Historical Park Need Your Help!

A box turtle (Terrapene carolina), one of the most frequently encountered turtle species on Island Loop Drive at Colonial National Historical Park.

NPS/Kai Scarangella

Turtles are moving about and crossing roads, especially in the spring and summer, at Colonial National Historical Park (NHP). They may be on the road while looking for food, a place to lay eggs, a mate, or a new home. The Island Loop Drive, a one-way road on Jamestown Island, passes through and near habitat used by turtles. To help prevent turtle injuries and deaths, park managers close the road to motorized vehicles for a few months each year. The road is kept open to bicyclists during these times. Unfortunately, this remains a source of some turtle deaths.

The park’s turtles include hatchlings that are only the size of a quarter, so it’s understandable why cyclists and motorists, and even pedestrians, may not always see turtles on the road. Colonial NHP managers are looking for ways to further reduce turtle deaths, and getting the word out is key!

Why care about turtles? Turtles matter for many reasons, including the important roles they play in the ecosystems they inhabit. They are remarkable creatures—long-lived, slow to mature, and with protective shells. The NPS's mission is to conserve turtles and other natural and cultural resources in parks for this and future generations.

Key Points

• Turtles are especially common on the road after overwintering and during the egg-laying season (generally March–June in eastern Virginia).
• Park managers may temporarily close Island Loop Drive to motorized vehicles during periods of high turtle activity to minimize turtle mortality.
• Some of the park’s turtles are very small, with hatchlings as small as a quarter! Others blend in with the road due to their coloration.
• Turtle surveys in the park found that bicycles also collide with turtles.
• Park visitors can help protect turtles by slowing down and watching for them on the road.

A live mud turtle (Kinosternon sp.) hatchling found on the road at Colonial National Historical Park.

NPS/Kai Scarangella

In addition to being about the size of a quarter, this hatchling is similar in color to the road.

NPS/Kai Scarangella

Visitors Play an Important Role

“Turtles have been migrating back and forth across the Island Loop Drive since it was built in the 1950s,” explained Colonial NHP Cultural Resources Program Manager Dwayne Scheid. “The remains of deceased turtles can be taken by scavengers relatively quickly, so the park didn’t have a good understanding of the amount of turtle loss that was occurring,” he continued. “During the COVID-19 pandemic, however, the road was closed to motor vehicles and became a popular spot with walkers and bicyclists. When the road reopened to vehicles, the walkers noticed a high level of turtle mortality and reported it to park staff. That’s when the park began to study the impacts of road activity on turtle mortality.”

According to Scheid, after an initial project in 2021 and 2022 to collect turtle sighting data with the help of volunteers, park managers decided to do a more in-depth study. They reached out to an expert in the field, Richard Seigel, Professor Emeritus of Biology at Towson University. In 2024, Seigel and his team, Kai Scarangella and Ryo Murasaki, began collecting data on turtle deaths on the road. Such information is crucial because Colonial NHP managers must balance protection of the turtles with providing visitors access to the park.

Island Loop Drive on Jamestown Island in Colonial NHP (left). It can be hard to see turtles due to lighting and other debris.

NPS/Kai Scarangella

In some places, the road is close to wetlands, where many of the park’s turtles live.

NPS/Kai Scarangella

Cycling for Data

Dr. Seigel’s team studied patterns of road mortality of turtles at Colonial NHP from March to October of 2024. They surveyed for live and dead turtles on the 4.8-mile stretch of the Loop Drive using a bike. They biked the road 281 times. The road was open to cyclists during the entire study period, and to motorized vehicles from early June to October for three days a week (Friday to Sunday).

Kai Scarangella, a Scientists in Parks intern, conducts one of many turtle surveys on Colonial’s Island Loop Drive.

NPS/Jeremiah Edwards

A mud turtle hatchling next to a bike wheel.

NPS/Kai Scarangella

What Did the Research Team Find?

Mud and Box Turtles were the Most Common Species

Dr. Seigel’s team found 330 individual turtles belonging to seven species during the road mortality study. A total of eight species were documented previously in the park on Jamestown Island. Mud turtles (two species, Kinosternon spp.) and box turtles (Terrapene carolina) were the most common species observed on the road. Red-bellied cooters (Pseudemys rubriventris) and painted turtles (Chrysemys picta) were the least common. The two other species recorded during the study were snapping turtles (Chelydra serpentina) and spotted turtles (Clemmys guttata).

The Smallest Turtles were the Most Likely to be Found Dead

Of the 330 turtles observed, 80% were found alive and 20% were found dead or badly injured. Mud turtles were the most often found dead (25% dead), while snapping turtles were the least often found dead (7% dead). This is probably because snapping turtles are so much larger, which makes them more visible and more easily avoided. Mud turtles are among the smallest turtles in the park.

There were “Hot Spots” and “Hot Moments”

The research team found that there were “hot spots” along the road—areas where turtle activity was highest—and “hot moments”—time periods when activity was greatest. An understanding of the location of “hot spots” (Figure 1) and the timing of “hot moments” can help park managers work to minimize turtle collisions. This can be accomplished through the placement of signs where turtles are most common, and by temporarily closing roads to motorized vehicles.

Figure 1. Map showing “hot spots”—areas of greatest turtle activity (yellow diamonds) on Jamestown Island Loop Drive. Only areas of greatest turtle activity are indicated, but it is possible to encounter turtles along any portion of the road. Plant symbols indicate wetlands, while plain green areas

NPS

Both Motorized Vehicles and Bicycles Cause Turtle Deaths

The study also led to the finding that both motorized vehicles and bicycles can cause turtle injuries and deaths. When the road was closed to motorized vehicles (e.g., in April and May), some deaths continued to occur. The research team concluded that most of the observed deaths of hatchling and juvenile turtles during this period were due to bicycles rather than NPS-authorized vehicles. This conclusion was based on shell damage, which was inconsistent with a heavy vehicle such as a truck. A hatchling (mostly less than 1 inch in shell length) or juvenile turtle run over by a truck would be flattened, whereas a collision with a bicycle would show much less damage.

Box turtle hatchling.

NPS/Kai Scarangella

Mud turtle hatchlings.

NPS/Kai Scarangella

Snapping turtle hatchling.

NPS/Kai Scarangella

Spotted turtle hatchling.

NPS/Kai Scarangella

Why Care about Turtles?

As stewards of the natural and cultural resources of national parks, the NPS has a responsibility to preserve turtles and other wildlife for this and future generations. Turtles are an important part of the ecosystems they inhabit. They eat plants and small animals. In turn, their eggs and hatchlings serve as food for birds, fish, mammals, and other reptiles. Turtles also help to cycle nutrients, improve water quality by scavenging carrion, and disperse plant seeds.

By existing within their protective shells, adult turtles have evolved the ability to resist most natural predators. The threat from cars, however, has caused many turtle populations to decline, especially in places near wetlands (e.g., Markle et al. 2026, Howell and Seigel 2019, Steen et al. 2006). The loss of turtles on roads is in addition to high egg, hatchling, and juvenile deaths through predation, and, together, this may lower recruitment below the level where populations are self-sustaining.

As a group, turtles are becoming more rare. They are among the most threatened major groups of vertebrates worldwide (Lovich et al. 2018). Over one-half of all turtle species are threatened or already extinct (Lovich et al. 2018).

We also care about turtles because they are cool—they are long-lived, take a long time to mature (10–25 years), and include aquatic and terrestrial species (although aquatic species lay eggs on land). Have you heard that the earliest turtles known were from the Permian Period—about 299 to 252 million years ago (Zug 2025)? This makes them older than dinosaurs!

How You Can Help

• When riding your bike or driving your car in Colonial NHP, slow down and watch out for turtles on the road. Sometimes collisions with wildlife cannot be avoided, but remaining aware of their potential presence and what they look like can help. Remember that these turtles can be as small as a quarter!
• Take note of signs posted along the road. To help visitors be aware during turtle season, the NPS may place signs in areas where turtles are especially common.
• Know before you go: Check the park website before visiting the park to see if there are any road closures on Jamestown Island for turtles.
• When visiting Colonial NHP, take a few minutes to learn about turtles. If you see it, visit the “Turtle Tent” (see photo below), where park staff share information about turtles.

Ryo Murasaki, a Biological Science Technician, holds a turtle shell and shares information with visitors at the Turtle Tent along Island Loop Drive.

NPS/Kai Scarangella

For More Information

To see what it’s like to conduct a turtle survey by bike, view this NPS video about the project:

Duration:

3 minutes, 43 seconds

In this episode, we visit Colonial National Historical Park on Jamestown Island where Scientists in Parks intern Kai bikes the island loop multiple times a day to monitor turtles.

References

Howell, H.J., and R.A. Seigel. 2019. The effects of road mortality on small, isolated turtle populations. Journal of Herpetology 53: 39–46.

Lovich, J.E., J.R. Ennen, M. Agha, and J. Whitfield Gibbons. 2018. Where have all the turtles gone, and why does it matter? BioScience 68 (10):771-781.

Markle, T.M., C.E Smith, and S.P. Stapleton. 2026. Turtles and turnarounds: Small animal exclusion fencing effectively reduces turtle road mortality. Biological Conservation 313 (2026), 111605.

Steen, D.A., M.J. Aresco, S.G. Beilke, B.W. Compton, E.P. Condon, C. Kenneth Dodd, H. Forrester, J.W. Gibbons, J.L. Greene, G. Johnson, T.A. Langen, M.J. Oldham, D.N. Oxier, R.A. Saumure, F.W. Schueler, J.M. Sleeman, L.L. Smith, J.K. Tucker, and J.P. Gibbs. 2006. Relative vulnerability of female turtles to road mortality. Animal Conservation 9(3):269–273.

Zug, G.R. 2025. Turtle. Encyclopedia Britannica, Inc. Available at https://www.britannica.com/animal/turtle-reptile/Origin-and-evolution (accessed 18 September 2025).

This article is based on the following report, funded by the NPS Natural Resource Condition Assessment Program: Seigel, R.A., K.D. Scarangella, and R.S. Murasaki. 2026. Assessment and mitigation of road mortality of turtles at Colonial National Historical Park. Available at: https://irma.nps.gov/DataStore/Reference/Profile/2316981