Ouachita Map Turtle
Pictured above: Ouachita Map Turtles can be distinguished from other map turtles by the blotches behind their eyes. These blotches are isolated (like the Common Map and unlike the False Map), however they are large and rectangular (unlike the Common). Also note the projections protruding from the vertebral keels along the carapace (top left).
Description: Like Common Maps and False Maps, Ouachita Map Turtles are medium-sized turtles, with adults reaching carapace lengths of 4.5 to 10.5 inches. The vertebral keels of these turtles are blunt but more distinct than the common map, while the posterior of the shell is serrated (pictured above). These turtles have an olive-green to brown carapace with dark blotches. Their plastron is light yellow with a distinct “road map” patterning along its’ margins. Their heads, legs and tails are olive or greenish with thin yellow lines. Unlike the Common Map or the False Map, Ouachita Maps have a large rectangular or oval blotch behind each eye. It is isolated, like the Common Map, but is larger and more rectangular. Other yellow spots also occur between the eye, upper mandible and in the center of the lower mandible. The eye is usually bright yellow. Ouachita Map Turtles are members of the family Emydidae.
Habitat/Ecology: Ouachita Map Turtles prefer big rivers with strong currents. They are also said to require much aquatic vegetation and ample basking sites. They are occasionally found in backwater sloughs as well as closer to the main channel. Females will consume both aquatic vegetation and insect larvae, while males are mostly carnivorous. Nest building seems to occur during June and July. In 2001, hatchling emergence occurred in late-August. Like all turtles, hatchlings are particularly susceptible to predation by birds, mammals, and fish, while the only threat to adults is humans. In 2001, I encountered many hatchling Ouachita Map Turtles that were killed by crows as they migrated from their nests to the water. This is likely the fate of many hatchling turtles. These turtles are said to over-winter in the soft sediments of water with high oxygen contents throughout the winter.
Remarks: Like other map turtles, Ouachita Maps spend a great amount of time basking but will escape into the water when people approach. They are very wary and, while I have encountered them more often than False Map Turtles, they still seem less abundant than the Common Map.
In 2001, I found several adult females as well as hatchlings near Green Island. I expect that they are found in other places around La Crosse as well. Within the state, these turtles also exist along the Wisconsin River.