What the shell? Turtles of the Highland Lakes

Highland Lakes roads see a rise in slow-moving traffic each spring and summer. It’s not caused by tourists who missed their turn but by a collection of turtles that call this part of the Texas Hill Country home.

Crossing a two-lane blacktop at an average speed of 3 mph can be a few of the most harrowing minutes of a turtle’s life. But when nature calls, our shelled friends get moving. It’s OK to lend a hand as long as you know how to properly and safely help a turtle cross the road. 

WHY DO TURTLES CROSS THE ROAD?

Freshwater turtles creep over roadways for a variety reasons, including mating, nesting, and moving from one body of water to another. March through July is mating and nesting season. While turtles live in or near water, they lay their eggs on land. 

WHAT’S CROSSING THE ROAD?

Viviana Ricardez of the nonprofit TexasTurtles.org sheds light on the species of turtles commonly found in the Highland Lakes and surrounding area. These jay-walkers include the red-eared slider, Texas cooter, Guadalupe spiny softshell, and common snapping turtle. You’ll also see Texas maps, Cagle’s maps, yellow muds, common musks, razor-backed musks, three-toed box turtles, ornate box turtles, and smooth softshells. 

Red-eared slider

A medium-size turtle whose skin and shell is olive/brown with yellow stripes. It has a thick red stripe behind each eye. It is native to Texas but an invasive species in much of the world.

Texas cooter

A large olive/brown turtle with yellow lines/patterns on the shell and skin. Its limbs might have reddish-orange lines. The plastron (see Turtle Anatomy 101 below) is a solid, creamy yellow. Distinctive markings include two large yellow stripes on the top of the head and others extending from under the eyes to the corners of the mouth and along the neck. Endemic to Texas.

Guadalupe spiny softshell

A large turtle species with females reaching up to 21 inches in length and males up to 9 inches. It has a very low-profile, olive-colored shell with white spots. The shell is covered in rough, leathery skin, and might have spine-like bumps along the front edge. The outer edges are flexible. The Guadalupe spiny softshell has a long, tubular snout. Endemic to Texas. Photo by John Rosford/iNaturalist

Common snapping

A large, heavy, muscular turtle with a large head. It can reach about 18 inches in shell length. The shell color ranges from tan to black and is small for the body, so the turtle can’t retract into it. The species has a long, jaggedly ridged tail that can be almost the length of its shell. Its skin is rough and bumpy. The common snapping turtle is known to be aggressive out of the water.

Texas map

A small turtle ranging up to 8 inches in shell length. This olive-green species has yellow markings all over that resemble a contour map. The markings might fade with age. Endemic to Texas. Photo by Danny Sanders/iNaturalist

Cagle’s map

A protected species and the smallest of map turtles. Females can reach about 8 inches in shell length, males half that. The slightly flattened shell is green-brown with raised vertebral scutes and a contour-map pattern. The turtle’s skin is light yellow with dark green stripes. A light-colored, V-shaped mark is often visible on top of the head between the eyes. Endemic to Texas. Photo by salamander9505/iNaturalist

Yellow mud

A small, olive-green turtle reaching about 5-7 inches in shell length. The smooth, domed shell has a yellow rim. The turtle’s skin can be olive, yellow, or gray with a yellow area on the throat. Photo by TLang88/iNaturalist

Eastern or common musk

A small turtle reaching about 3-4 inches in shell length. The domed shell and skin range from brown to black in color. The common musk has two heavy yellow lines extending from the tip of its nose to its neck as well as one line above each eye and another below. When disturbed, the turtle will emit a foul-smelling liquid from its musk glands. Photo by diomedeaexulansli/iNaturalist

Razor-backed musk

A small turtle typically under 7 inches in shell length. The shell is light brown-orange with dark spots or streaks that often fade with age. The structure has a prominent ridge or keel that slopes steeply, giving the turtle a triangular appearance from the front and back. Its skin is gray to brown with small dark spots. Photo by chrisinlouisiana/iNaturalist

Three-toed box

A small, olive-brown turtle typically under 7 inches in shell length. It has very thin, yellow-orange lined patterns on each scute of its high-domed shell. Its skin is dark brown-black with orange-yellow blotches on the head and limbs. Most have three toes on each rear limb.

Ornate box

A small turtle with a 4- to 5-inch dark brown-black shell, which has many yellow lines, often in starburst patterns, and a yellow stripe running down the middle. The plastron is similarly patterned. The skin is gray-brown with yellow-orange blotches; the chin and upper jaw are yellow-green. Photo by dianaterryhibbitts/iNaturalist

Smooth softshell

A medium-size turtle, 7-14 inches in shell length, that has a pancake-like appearance. Its shell is smooth and leathery, very low profile, and olive to orange-brown in color. The outer edge is soft and lined with a light yellow band beginning just behind the front limbs. The turtle’s underside, including under its limbs, is white-gray. It has a long, tubular snout. Photo by John Williams/iNaturalist

TURTLE ANATOMY 101

• Carapace: top shell
• Plastron: bottom shell
• Bridge: bony structures that connect the carapace to the plastron
• Scutes: scales made of keratin that cover the carapace
• Limbs: front legs (pectoral flippers) and hind legs (pelvic flippers) with webbed feet and long claws
• Tail: used for protection and mating (never pick up a turtle by the tail)
• Beak: hard layer of skin covering the upper and lower jaws with tooth-like serrations for biting 

TRUE TURTLE FACTS

• A turtle’s skeleton is fused to its shell, so it cannot come out of it like in cartoons.
• Turtle populations are declining significantly due to habitat loss, vehicle run-ins, pollution, poaching, and illegal wildlife activities.
• Turtles are cold-blooded; their body temperature is regulated by the environment.
• Male turtles have longer claws and tails than females.
• Female turtles are typically much larger than males.
• Turtle scutes (scales on the shell) are made of the same material as human hair and fingernails.
• Turtles can feel pain and pressure through their shells, just as humans can through their fingernails.
• A turtle’s bridge allows it to retract inside its shell, protecting its vulnerable parts.
• Common musk turtles will walk on the bottom of a stream or pond while foraging, instead of swimming.
• Turtles are egg-laying reptiles in the Testudines family and have a body encased in a shell.
• Tortoises (dry land) and terrapins (marsh) are turtles that live in different habitats.

jgreenwell@thepicayune.com