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Q: I came across at least seven nests of turtle eggs last June along a trail near Glencoe. All the eggs in each nest were eaten. Which turtle species laid these eggs? And what ate them?

Unfortunately, most turtle species’ eggs are similar in color, shape, shell texture, and size, making them difficult to identify. In most cases, to be accurate you must either see the turtle laying the eggs or witness the young hatching. 

However, for this photo, it’s possible to rule out snapping turtles and softshell turtles. Those species have eggs that are round, rather than elliptical shaped. And because these eggs are not pale and pinkish white, it’s unlikely they were laid by a Mississippi mud turtle or an eastern river cooter. These eggs probably weren’t laid by a chicken turtle, Blanding’s turtle, or a yellow mud turtle either. Those three species are endangered in Missouri, meaning they’re rarely seen. And because the shells don’t appear hard and brittle, the eastern musk turtle is a less-likely culprit. They are too large to be box turtle eggs. Finally, the southern painted turtle’s Missouri range is the Bootheel, not St. Louis County.

Thus, by a process of elimination, a few of Missouri’s 18 turtle species can be discarded. However, that still leaves several possible species, including the western painted turtle, three of the map turtles (Graptemys), and Missouri’s red-eared slider.

“Based upon what I believe are the length of the elongated eggs, my first guess would be red-eared sliders. But they could be western painted turtles’ eggs,” said Missouri State Herpetologist Jeff Briggler. “And, if they are very close to a large creek or stream, it is possibly one of the map turtle species.”

All turtles lay eggs on land. Most select well-drained, sandy, or loose soil to deposit their eggs. The site usually faces south or southeast. 

Many animals eat turtle eggs. 

“This is definitely a depredated nest, likely from raccoons,” Briggler said. 

Q: Last July, my wife noticed bats were flying near our front door. I went outside and took a closer look at what I thought was a huge bat on a shutter. I believe it to be a western ratsnake, but I am less certain of the bat species. Can you tell me what type it is?

Based on the size, color, and presence of a keeled calcar (or spur that supports the web of skin between the hind leg and tail), this appears to be a big brown bat being eaten by a western ratsnake. 

Bats contend with many wild predators, including minks, raccoons, skunks, domestic cats, rats, hawks, owls, and snakes. Western ratsnakes, commonly called black ratsnakes, kill their prey by constriction, but they also can swallow smaller prey. They are excellent climbers and often raid tree cavities and nesting boxes for eggs and young. Ratsnakes have been known to climb cave walls and prey on bats mid-flight as they exit the roost. 

Placing a bat house away from trees or hanging branches can prevent predators from reaching bats. Usually, placing a bat house on a tall pole or the side of a building is the best way to ensure this protection. However, predatory snakes can be an exception to the “poles are safe” rule, as snakes have been known to climb them. But installing a predator baffle can reduce the chances of that occurring.