The Graptemys pseudogeographica, or False Map Turtle come in many different sizes. The female is normally larger then the male as an adult. The adult female shell ranges from 12 to 27 cm (5 to 11 in.) in length, while the adult male shell ranges from 9 to 15 cm (3 to 6 in.) in length. The false map turtle has a moderately sized olive to brown carapace (back) with a saw-tooth edge along the center of the back and rear border. False map turtles are also known as "sawback" turtles because their saw-tooth edges resemble the teeth of a saw blade. Dark spots are scattered rather evenly, with one spot per scute (external bony plate), across the back and hind rim of the carapace. False map turtles have yellow plastrons (bellies) with dark lines around the edges and within the seams. As false map turtles age, the well developed designs fade and the edges of the shell dull. Distinct yellow lines cover the head, neck, and limbs, and a characteristic yellow "L" is mirrored across the top of the head. Males and females differ in appearance. Males have longer, thicker tails and longer claws on the front feet than females.

 

False map turtles populate areas of the Mississippi and Missouri Rivers and their basins in Arkansas, Iowa, Indiana, Illinois, Kansas, Kentucky, Louisiana, Minnesota, Missouri, Nebraska, North Dakota, Ohio, Oklahoma, South Dakota, Tennessee, Texas, and Wisconsin. False map turtles are found predominantly in large rivers and backwaters, but also in bayous, oxbows, lakes, ponds, sloughs, drowned forests, and occasionally marshes. They prefer water with slow currents, places to bask, and abundant aquatic vegetation. At one time, false map turtles were common turtles of the northern Missouri River, a common resident of Lake Oahe and Lake Sharpe. Now, the false map turtle is a state-protected species. At present, false map turtles are generally rare in Lake Oahe and Lake Sharpe, although they can be locally common. False map turtles are more regularly found below Gavins Point Dam.

 

Natural and man-made factors affect false map turtles throughout their range. Natural factors include natural weather extremes, such as dry spells. Man-made factors consist of agricultural run-off, flood control , and urbanization, all of which cause habitat degradation or destruction. Loss of habitat plays a major role in the numbers of false map turtles since these turtles already face a limited range. False map turtles are rare residents in certain areas of the Missouri River, and where false map turtles commonly dwell in the Missouri River, their numbers are no longer as plentiful as in the past. False map turtles depend on sandy shorelines and large, natural river systems. Because the Missouri River continues to change ecologically, false map turtles may be affected well into the future. For this species to remain a Missouri River resident or, more specifically, a South Dakota resident, we need to maintain and enhance protection along the Missouri River. Hopefully, this will ensure the existence of false map turtles as well as other rare or protected species of the Missouri River for future generations to enjoy.

 

False map turtles normally feed early in the morning on aquatic insects, fish (especially dead fish), aquatic plants, and crayfish. Individuals survive winter by digging into the mud on the bottom of the river. Dry winters pose a large threat for false map turtles. With a higher potential to freeze in shallow waters, false map turtles experience increased winterkills. Some of the animals that this turtle may have to compete with are, raccoons, otters, alligators, herons, kingfishers, snakes, big fish. They can compete with them by using their claws and turtles are very sneaky and quiet so they can sneak up on their prey. They can sneak away from their prey by their sneakiness and quietness. One interesting fact I learned while doing this report is that the females are larger then the males.

 

Author: Sara W.

Published: 02/2009

 

Sources: http://www.ben.edu/museum/falsemapturtle.asp http://www.sdgfp.info/Wildlife/Diversity/Digest%20Articles/false_map.htm

 

Photo Credit: http://upload.wikimedia.org/wikipedia/commons/0/02/20051114135926.jpg