Red Eared Slider (Trachemys scripta elegans), Schoepff, 1792
IDENTIFICATION: 5-12 inches (**-** cm). The carapace is oval from a dorsal perspective and there may be serrated edges present on the rear marginal scutes. Among mature specimens, the carapace contains numerous longitudinally oriented shallow ridges. These become more pronounced as the turtle grows older. A low mid-dorsal keel is also present on the carapace. A broad red stripe is present behind the eye. However, this colorful mark like other color markings becomes faded with advanced age. Females are the larger of the sexes.
Juveniles are the most colorful with yellow lines interlacing a lime green base coloration. As the turtle grows the yellow lines become less pronounced. Adults often disply yellow lines, but they are much finer and less distinguished than those present on juveniles. Old specimens darken with age and old males often lose all recognizable patterns present on their carapace, head and plastron during their youth.
Asides from their difference in size, mature males posses a longer and wider tail with a cloacal opening that extends beyond the posterior margin of the carapace. Males also develop elongated fore claws that are used in underwater courtship behavior to vibrate water currents alongside the female's ears.
ABOVE: This male specimen was photographed after it crawled out of a duckweed filled cattle pond in San Saba County, Texas.
With her shell covered in algae this female from Travis County, Texas would have gone unnoticed had she not ventured onto land.
NATURAL HISTORY AND ECOLOGY: Red eared sliders are the most widespread of aquatic turtles in Texas. They are capable of living in a wide variety of habitats including, but not limited to: lakes, ponds, rivers, swamps, bayous, creeks, and even brackish estuaries along the Gulf coast.
Spring fed creek in Travis County
Brackish marsh in Cameron County, note the turtle tracks through the sand bar.
Seaonal wetlands such as this ephemeral pond in Tarrant County (left) are important resources for many species of freshwater turtles. However, as they dry the turtles leave them for permanent sources of water such as this section of the trinity River in Tarrant County (right).
Although they are aquatic, red ear sliders are often seen on land crossing roads. Terrestrial movements are often inspired by the need to lay eggs and the need for better aquatic habitat. The wetter spring months often provide a suitable climate for various freshwater turtles to make terrestrial excursions. These two sliders were found walking alongside a road following a heavy thunderstorm in Clay County, Texas.
Reproductive behavior usually takes place between March to August and begins with the male courting the female. All reproductive activity with the exception of egg laying takes place in the water. Courtship behavior involves the male orienting himself in front of the female face to face. He then extends his front legs until the elongated front claws are aligned next to her tympanum. Then with rapid movements in his wrist he gently strums the water alongside her head. Courtship may take up to one hour to complete. Should the female be receptive to his advances copulation ensues. The male then orients himself behind the female and mounts the posterior portion of her carapace where he can align his cloaca with hers. Mating usually only requires 10 to 15 minutes.
Females lay their eggs from April to August. Hatching generally requires between 60 to 90 days. The sexes of red eared sliders are determined by their incubation temperature.
Although they are considered to be the most abundant and common species of freshwater turtle in Texas, red ear sliders still face challenges from the form of human activities ranging from habitat loss (above left), pollution and trapping for Chinese food markets while the eons -old pressure of nest being raided by predators continues (above right).
This hatchling used its egg-tooth (caruncle) to cut through the leathery shell of its egg. The caruncle falls off within a week or two of hatching.
After hatching, red ear sliders are primarily carnivorous however, their dietary preference shifts towards vegetative matter as they mature. Adults primarily consume aquatic vegetation such as duckwed, algae, hyacinth, and various other aquatic vascular plants. Because of this, red ear sliders are important for for aquatic ecology by keeping waterways clear of excess and sometimes invasive aquatic vegetation. Even though adults are primarily vegetarian they are still opportunisitc for other types of food items and will not hesistate to consume a variety of invertebrates and small vertebrates which include but are not limited to: worms, snails, crayfish, insects, arachnids, small amphibians, reptiles, birds and mammals. It is an inaccurate notion that this turtle poses a threat to fish populations. Most healthy fish are toofast and wary to be caught by the red ear slider and the removal of any old or sick fish is a manner by which the overall health of the remaining fish population is improved. Sliders will also consume carrion that has fallen into the water. Not only are these attractive turtles interesting to observe and study but they provide a beneficial service to man by improving the quality of waterways.
