Our Park Species Lists page has a complete list of turtles and other species found in the Big Thicket.
Alligator snapping turtle
Photo: USFWS, Gary Stolz
Alligator Snapping Turtle
Macrochelys temminckii
This large turtle gets its name from its formidable jaws and ridges along its shell that resemble the ridges on the backs of alligators.
They are not commonly seen because they spend almost all of their time in the water, though females will venture onto land when they are nesting. Alligator snapping turtles have been recorded to be as large as 250 pounds (though it’s possible that they can grow larger, it hasn’t been verified).
They are opportunistic carnivores that will eat whatever they can get, but mostly live off of fish, molluscs, and amphibians. They’ve also been known to snatch mammals who get too close to the water. Alligator snapping turtles frequently live to be over a hundred and it is thought that they can live to be two hundred years old. When you encounter alligator snapping turtles you should give them their space! They can bite off fingers, but they typically won’t bite unless provoked.
Alligator snapping turtle females will build nests for their eggs in late spring. Mothers do not take care of their young after laying the eggs. Like alligators, the temperature of the nest determines whether the baby alligator snapping turtles will be male or female. Warmer temperatures produce more males, so rising temperatures in response to climate change could pose a threat to alligator snapping turtles in the future. Alligator snapping turtles are currently considered vulnerable due to habitat destruction and harvesting for meat and the illegal pet trade.
Eastern box turtle (Terrapene carolina)
NPS Photo
Box Turtles
Genus: Terrapene
There are more than one species of box turtle found in Big Thicket National Preserve, and they are one of the commonly seen turtles in the area.They are most active during the day, which could explain why they are seen more often than more nocturnal reptiles.
Box turtles are omnivorous, eating everything from berries to fungi to insects. They prefer to be near water sources, but are also frequently seen trying to cross the road. Box turtles all have domed shells that they can retreat into when they feel threatened. Like many reptiles, turtles brumate to make it through the winter, burrowing into the soil to escape cold winter temperatures.
Box turtles lay eggs in June or July. Females will often lay their eggs at night, despite being diurnal. Females will dig out nests in soil in sunny areas with their hind legs. Box turtles usually lay 3-6 eggs. Eggs generally hatch two to three months after being laid, but if the eggs are laid late in the season eggs will sometimes remain in the ground until spring when temperatures are warmer.
Allard, H. A. (1935). The natural history of the box turtle. The Scientific Monthly, 41(4), 325-338.
Ligon, D. B., & Lovern, M. B. (2009). Temperature effects during early life stages of the alligator snapping turtle (Macrochelys temminckii). Chelonian Conservation and Biology, 8(1), 74-83.
Reed, R. N., Congdon, J., Gibbons, J. W., & Drawer, E. (2002). The Alligator Snapping Turtle.
Stickel, L. F. (1950). Populations and home range relationships of the box turtle, Terrapene c. carolina (Linnaeus). Ecological Monographs, 20(4), 351-378.
In February 2021, an extreme cold front swept the south Texas coast, rendering tens of thousands of endangered sea turtles lethargic and helpless. Working against the clock, a dedicated team of rescuers rushed to save them. A new study indicates long-term impacts.
Locations:Golden Gate National Recreation Area, Point Reyes National Seashore, Presidio of San Francisco
Thanks to park biologists and partners, visitors can again spot western pond turtles in popular parts of Golden Gate National Recreation Area and the Presidio of San Francisco where they had vanished. But the turtles still need help growing their numbers. Cue an unlikely conservation hero: Canis lupus familiaris, the domestic dog! This May and June, specially trained dogs are helping biologists find and protect vulnerable turtle nests in the parks.
Locations:Cape Hatteras National Seashore, Cape Lookout National Seashore, Catoctin Mountain Park, Chesapeake & Ohio Canal National Historical Park, George Washington Memorial Parkway, Harpers Ferry National Historical Park, Hopewell Furnace National Historic Site, National Capital Parks-East, Prince William Forest Park, Rock Creek Park, Upper Delaware Scenic & Recreational River, Valley Forge National Historical Parkmore »
Parks are a great place to appreciate turtles in their natural habitat. NPS is now studying at-risk land turtles in the Mid-Atlantic to better understand how to help them survive into the future.
Locations:Golden Gate National Recreation Area, Muir Woods National Monument
In 2017, scientists released a group of western pond turtles—California’s only native freshwater turtle—at Muir Beach Lagoon as part of a broader reintroduction effort. Since then, biologists have been carefully monitoring the cohort and their movements. But recent chance sightings took them by surprise.
Locations:Acadia National Park, Appalachian National Scenic Trail, Boston Harbor Islands National Recreation Area, Eleanor Roosevelt National Historic Site, Home Of Franklin D Roosevelt National Historic Site, Marsh - Billings - Rockefeller National Historical Park, Minute Man National Historical Park, Morristown National Historical Park, Saint-Gaudens National Historical Park, Saratoga National Historical Park, Saugus Iron Works National Historic Site, Vanderbilt Mansion National Historic Site, Weir Farm National Historical Parkmore »
Offices:Inventory and Monitoring Division
Box turtles have evolved the familiar turtle shell to near perfection, holding the ability to close of its head and legs within its hinged under shell.
When sea turtles hatch in areas with lots of light pollution, they can get disoriented and not make it into the ocean. This episode tracks the young volunteers in the Pensacola, FL area working to help turtle hatchlings make it to the sea.
As part of a collaborative western pond turtle reintroduction project, Golden Gate biologists have been using radio telemetry to track the movements of released turtles. We also conduct annual health checks of the turtles at the end of each summer through trapping. Trapping for the 2022 season occurred in late-August through early-September. Unlike previous years, this year's health check marks the official end of the radio telemetry monitoring program.
Locations:Golden Gate National Recreation Area, Point Reyes National Seashore
Offices:Inventory and Monitoring Division
Meet Darren Fong, aquatic ecologist for Golden Gate National Recreation Area and lead scientist for the SFAN streamflow monitoring program. Discover how Darren's fascination with aquatic life and freshwater ecosystems began and learn how he got to be where he is today.
Scientists Greg LeClair from University of Maine - Orono is developing a new tool to find rare animals by finding their DNA in the water without having to actually see the animal. Check out this research brief to find out more about how Acadia National Park is a living laboratory for research and scientific discovery.
