Survival: Snapping Turtle

Why did the snapping turtle cross the road? To find a good place to lay her eggs. Why did somebody deliberately run over her? Good question.

Snapping turtles (Chelydra serpentina) aren’t usually out and about on the road past Owl Acres. They’d rather stay near the creek. The females have one imperative this time of year, though, and that Is to find the right place to lay their eggs. They like sandy areas like the shoulder of our gravel road. Left to her business, a female snapping turtle will carefully select her nesting site. Then she’ll spend about an hour and a half digging a hole. When she’s satisfied with her nest hole, she’ll lay from 10 to 30 eggs, each about an inch long. She’ll cover up the nest with dirt, tamp it down and camouflage it. When she’s done, she’ll leave the nest to incubate on its own, and go back to her home in the creek. In spite of these efforts, her nest runs about a 90% chance of being discovered and raided by predators like raccoons, snakes, skunks and foxes.

If the eggs do survive, they will incubate for 90 to 120 days. Temperature determines whether the hatchling will be male or a female. If the weather is cool, you’ll get mostly males. If it’s warm, you’ll get mostly females. This sexing scheme developed in prehistoric times long before X and Y chromosomes evolved. The ancestors of our snapping turtle reach back 215 million years, and by 40 million years ago they looked pretty much like they do today. Turtles survived several extinctions, including the one 65 million years ago that ended the reign of the dinosaurs.

Snapping turtles have a reputation for being vicious biters. I wouldn’t want to test it, although expert handlers say otherwise. Snapping turtles have triangular heads with hooked beaks and long necks. If they’re threatened, they will strike, snapping their jaws together, hopefully short of a human’s hand. They don’t have teeth, but they do have jaws with sharp surfaces made for cutting. Turtles have excellent eyesight and hearing both in and out of the water.

Snapping turtle hatchlings are about the size of a quarter. When they hatch, they somehow know where to go to find water. If they survive to about three inches long, which is not statistically likely, they have a good chance of growing to adulthood. Turtles have long lives compared to most other animals. It takes a snapping turtle 10 to 16 years to become sexually mature.

The shell, or carapace, of an adult snapping turtle is on average 8 to 16 inches long, and continues to grow throughout the turtle’s life. An adult turtle can weigh up to 40 pounds. Their shells range in color from black to brown to olive-gray and are often covered in algae or mud. Their skin ranges from light brown to rusty orange or yellow. The underside of the turtle is protected by a boney plate called a plastron. The plastron is connected to the carapace by two narrow bridges. The turtle’s neck and tail are each about as long as the carapace, and the tail has spines on it. The turtle’s feet are webbed and have claws. The front legs are short and powerful with feet as big as a human hand. 

Snapping turtles are fresh-water turtles and are native to North America. They spend most of their lives sitting on the bottom of a shallow body of water with their heads out. They can swim but usually walk across the bottom. They are nocturnal, and hunt at night, catching slow-moving fish and eating plants growing in the water. They are too slow to catch healthy game fish, though, contrary to what some fishermen think.  

Some people target snapping turtles on the road because they think erroneously that the turtles compete for healthy game fish. Unfortunately, these turtles are not protected by Iowa law. They can be trapped or taken with hook and line or by hand. The only requirement is a valid fishing license and a limit of 100 pounds of total turtles, or 50 pounds of turtle meat.

Adult snapping turtles have no natural enemies, unless you count people and cars and trucks on the road. They can live in the wild for 40 or 50 years, dying in the winter of old age. Hunting and trapping snapping turtles is not regulated, and scientists are concerned that the population will crash if trapping continues.

Wisdom, longevity and resilience are characteristics attributed to turtles throughout the world, and some creation myths have a giant turtle supporting the entire world on its back. My personal introduction to the wisdom of a turtle came in kindergarten in the well-known folk tale of the tortoise and the hare–steady wins the race.

Photo by Author. Alt text: Road-killed snapping turtle lost the battle with its only predator.