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The ornate box turtle (''Terrapene ornata ornata'') is one of only two terrestrial species of turtles native to the Great Plains of the United States. It is one of the two different subspecies of ''Terrapene ornata''. It is the state reptile of Kansas.〔http://www.stateanimals.com/states/kansas/index.html〕 It is a relatively small turtle, that is currently listed as threatened in Illinois〔http://www.dnr.illinois.gov/ESPB/Documents/ETChecklist2011.pdf〕 but is of concern and protected in six Midwestern states (Colorado, Iowa, Indiana, Nebraska, Kansas, and Wisconsin).〔Redder, AJ, CK Dodd, D Keinath, D Mcdonald and T Ise, 2006. ("Ornate box turtle (Terrapene ornata ornata): A technical conservation assessment" ). USDA Forest Service, Rocky Mountain Region. Accessed November 29, 2008. Peer review administered by the Society for Conservation Biology〕 Males and females generally look alike but males are often smaller; there is color variation with yellow lines from the center of the shell to the edges through gray, red-brown, or black coloration.〔 Besides the size, males can be distinguished from females in several ways; a large curved inner claw on the back feet, a cloacal opening that is farther back in males, a longer and thicker tail, and reddish color on the legs and occasionally on the jaw.〔 == Home range and temperature == The home range of the ornate box turtle covers a large area of the Midwest, from Wisconsin to the Gulf of Mexico and from Louisiana to Colorado.〔 It was first discovered in Nebraska in 1795, where "vast numbers" were found.〔 The turtle is usually found in grasslands and on land rather than in water; they have been found in all habitat types of the Great Plains except aquatic, though most references indicate they prefer open grass or prairie lands.〔 Several studies indicate that the ornate box turtle needs three specific types of microhabitats in order to survive: # grass (prairie) areas for feeding that have some free water # areas where females can nest and burrow into the soil to overwinter # sites for resting and thermoregulation where turtles can bury themselves in soil to protect themselves from extreme temperatures and to avoid dehydration in summer and eat their own eggs 〔〔Converse, SJ and JA Savidge, 2003. Ambient temperature, activity, and microhabitat use by ornate box turtles (Terrapene ornata ornata). J. Herpetol. 37(4):665-670.〕〔Bernstein, NP and RW Black, 2004. Thermal environment of overwintering ornate box turtles, Terrapene ornata ornata, in Iowa. Am. Midl. Nat. 153:370-377;〕 Water is important for this turtle to regulate body temperature in hot weather and to replace body water after hibernation, but they do not spend large amounts of time in flowing or standing water.〔〔 The ornate box turtle, like all reptiles, is ectothermic, which means that its body temperature is affected by the environmental temperature and the environmental temperature affects its movement.〔〔Claussen, DL, R Lim, M Kurz and K Wren, 2002. Effects of slope, substrate, and temperature on the locomotion of the ornate box turtle, Terrapene ornata. Copeia 2002(2):411-418.〕 In the hottest part of the day, the turtle is less active because movement increases body temperature and makes it harder for the turtle to keep cool, and when the temperature is lower(dawn and dusk), the turtle is more active.〔 Additionally, the turtles use their habitat to help control their body temperature.〔 Shrubs are commonly utilized for the shade the plants produce, helping to further regulate the animal's temperature. Open areas of sand are also important parts of the turtle's habitat for digging holes to burrow in.〔 In winter, ornate box turtles hibernate underground in burrows. They burrow in at about the same time in the fall and come out within 7–14 days of each other.〔 They can survive freezing soil temperatures for many days.〔 The depth of nest cavities in Nebraska in 1997 and 1998 was 16.8 cm and the depth of hatchlings buried in the soil ranged from 56.3 cm to 64.7 cm.〔Converse, SJ, JB Iverson and JA Savidge, 2002. Activity, reproduction and overwintering behavior of ornate box turtles (Terrapene ornata ornata) in the Nebraska Sandhills. Am Midl. Nat. 148:416-422.〕 In Nebraska, winter burrows were dug after October and turtles stayed in them until April and all of these turtles were in individual burrows.〔 The home range area of ornate box turtles varies a lot from study to study, from as small as 0.12 hectares to as large as 36.4 hectares.〔〔 The large variability in home range size estimates can be affected by seasonality, body size and age, time period of observation, presence of roads or other structures, statistics used, and other factors.〔 The ornate box turtle has a high degree of philopatry, which means that it returns to the same area year after year, and it usually prefers the same habitat type as the original one.〔Bernstein, NP, RJ Richtsmeier, RW Black and BR Montgomery, 2006. Home range and philopatry in the ornate box turtle, Terrapene ornata ornata, in Iowa. Am Midl. Nat. 157:162-174.〕 Ornate box turtles were two times more likely to be found in the same sub-habitat type as the original and even more likely to be in a sub-habitat next to the original habitat than areas two sub-habitats away.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「ornate box turtle」の詳細全文を読む スポンサード リンク
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