Ornate box turtle
Encyclopedia
The Ornate box turtle (Terrapene ornata ornata) is one of only two terrestrial species of turtle
s 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
. It is a relatively small turtle, that is currently not endangered or threatened but is of concern and protected in six Midwestern
states (Colorado
, Iowa
, Indiana
, Nebraska
, Kansas, and Wisconsin
). 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 cloaca
l opening that is farther back in males, a longer and thicker tail, and reddish color on the legs and occasionally on the jaw.
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:
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. 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. Shrub
s 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. 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 hectare
s 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. 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.
, with no particular dietary preferences; as an opportunistic feeder, it eats whatever is available in any given location or season. Grasses, berries, insect
s and other invertebrate
s (caterpillar
s, grasshopper
s, beetle
s, earthworm
s), fruits, vegetables, and carrion
(mammals, birds, amphibians, snakes, and even other turtles). This varied diet means the turtle has very little competition for available food resources.
Birds, such as crow
s, raptor
s, and raven
s; domestic cat
s and dog
s; opossums; raccoon
s; skunk
s; snake
s; and even adult box turtles; are potential predators of young turtles. The turtle has very little means of self-defense other than closing the shell, though they may potentially bite if handled.
Until recently, there was very little scientific knowledge of diseases and parasites among the turtle populations; early studies showed that a genus of fly sometimes infested the legs of these turtles and caused death by starvation because their movement was impeded. More recently, it has been found that respiratory, metabolic, and shell diseases, common in desert tortoises, also fairly common in land turtles such as the ornate box turtle; and that nutritional deficiencies contribute to these other diseases.
The age of ornate box turtles has been estimated by counting growth rings for many years. This is similar to estimating the age of a tree but for turtles, the “rings” are lines that form on part of the shell that are like scales and the longer a turtle lives, the more rings are formed. However, using the rings to estimate age is not always reliable. The shell does increase in size as turtles get older, even though its weight makes it heavy to carry around.
Agriculture – agriculture in the Great Plains has been the worst problem for the ornate box turtle recently because it has taken away lots of acres of land, destroyed habitat, caused more traffic, and created small, isolated areas of prairie. In addition, the small pieces of prairie mean more edge habitats, which causes more predators to live there and that increases predation of the box turtle that is already suffering from less total habitat area. Other agricultural factors that are a problem for the ornate box turtle are fences, water troughs, cattle (trampling), mowing, and other machinery.
Development – houses and other building construction causes loss of habitat similar to agriculture, but also increased removal for pets, predation by dogs, and greater predation to crows and raccoons that increase around human living areas. Where housing developments are built, there are also more roads. The box turtle feeds on carrion when it is available and on roads road-kill is a large source of carrion and a large cause of death of ornate box turtles.
Over-exploitation – a huge number of ornate box turtles have been collected for sale in pet stores, and individuals have always collected some turtles. The commercial trade has had a large effect on the Great Plains populations and if it continues, the result will be a serious decline in turtles.
Probably the biggest factor that affects the ornate box turtle is interactions with human so any action that minimizes contact is helpful. Working to keep large areas of habitat undisturbed is also helpful. Managing weeds with a minimal amount of herbicide and knowing what chemicals are in the herbicide and how they affect turtles is important. The use of fire and mowing to control weeds should be done carefully when turtles are inactive or in burrows to keep cool. The public is not likely to want to stop collecting turtles, even if the pet trade were prohibited, because people like to look at turtles and other forms of nature. Nebraska and Louisiana have prohibited collecting ornate box turtles, but New Mexico and Texas have not.
Educating the public about the risks to the ornate box turtle will be difficult but should be part of the conservation effort. One conservation effort that might be helpful is removal of predators from an area where many turtles are found; one study found that removing raccoons was helpful but it also leads to the question of balance in nature and which animals are more important. Some biologists have suggested that moving turtles from healthy populations to areas where the turtle is struggling might be an option but this is difficult and might be a last resort.
Habitat loss is the biggest problem for the ornate box turtle and isolated habitat areas have isolated groups of turtles that lose genetic diversity and experience bottlenecks that decrease their survival.
Because the ornate box turtle has a long life-span and doesn’t reproduce until late, it will be difficult to manage conservation of this turtle.
Turtle
Turtles are reptiles of the order Testudines , characterised by a special bony or cartilaginous shell developed from their ribs that acts as a shield...
s native to the Great Plains
Great Plains
The Great Plains are a broad expanse of flat land, much of it covered in prairie, steppe and grassland, which lies west of the Mississippi River and east of the Rocky Mountains in the United States and Canada. This area covers parts of the U.S...
of the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
. It is one of the two different subspecies
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
of Terrapene ornata
Terrapene ornata
Terrapene ornata is a species of North American box turtle sometimes referred to as the western box turtle or ornate box turtle.- Taxonomy :There are two subspecies of T. ornata:...
. It is the state reptile of Kansas
Kansas
Kansas is a US state located in the Midwestern United States. It is named after the Kansas River which flows through it, which in turn was named after the Kansa Native American tribe, which inhabited the area. The tribe's name is often said to mean "people of the wind" or "people of the south...
. It is a relatively small turtle, that is currently not endangered or threatened but is of concern and protected in six Midwestern
Midwestern United States
The Midwestern United States is one of the four U.S. geographic regions defined by the United States Census Bureau, providing an official definition of the American Midwest....
states (Colorado
Colorado
Colorado is a U.S. state that encompasses much of the Rocky Mountains as well as the northeastern portion of the Colorado Plateau and the western edge of the Great Plains...
, Iowa
Iowa
Iowa is a state located in the Midwestern United States, an area often referred to as the "American Heartland". It derives its name from the Ioway people, one of the many American Indian tribes that occupied the state at the time of European exploration. Iowa was a part of the French colony of New...
, Indiana
Indiana
Indiana is a US state, admitted to the United States as the 19th on December 11, 1816. It is located in the Midwestern United States and Great Lakes Region. With 6,483,802 residents, the state is ranked 15th in population and 16th in population density. Indiana is ranked 38th in land area and is...
, Nebraska
Nebraska
Nebraska is a state on the Great Plains of the Midwestern United States. The state's capital is Lincoln and its largest city is Omaha, on the Missouri River....
, Kansas, and Wisconsin
Wisconsin
Wisconsin is a U.S. state located in the north-central United States and is part of the Midwest. It is bordered by Minnesota to the west, Iowa to the southwest, Illinois to the south, Lake Michigan to the east, Michigan to the northeast, and Lake Superior to the north. Wisconsin's capital is...
). 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 cloaca
Cloaca
In zoological anatomy, a cloaca is the posterior opening that serves as the only such opening for the intestinal, reproductive, and urinary tracts of certain animal species...
l 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 MexicoGulf of Mexico
The Gulf of Mexico is a partially landlocked ocean basin largely surrounded by the North American continent and the island of Cuba. It is bounded on the northeast, north and northwest by the Gulf Coast of the United States, on the southwest and south by Mexico, and on the southeast by Cuba. In...
and from Louisiana
Louisiana
Louisiana is a state located in the southern region of the United States of America. Its capital is Baton Rouge and largest city is New Orleans. Louisiana is the only state in the U.S. with political subdivisions termed parishes, which are local governments equivalent to counties...
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 (prairiePrairiePrairies are considered part of the temperate grasslands, savannas, and shrublands biome by ecologists, based on similar temperate climates, moderate rainfall, and grasses, herbs, and shrubs, rather than trees, as the dominant vegetation type...
) 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
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. 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. Shrub
Shrub
A shrub or bush is distinguished from a tree by its multiple stems and shorter height, usually under 5–6 m tall. A large number of plants may become either shrubs or trees, depending on the growing conditions they experience...
s 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. 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 hectare
Hectare
The hectare is a metric unit of area defined as 10,000 square metres , and primarily used in the measurement of land. In 1795, when the metric system was introduced, the are was defined as being 100 square metres and the hectare was thus 100 ares or 1/100 km2...
s 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
Philopatry
Broadly, philopatry is the behaviour of remaining in, or returning to, an individual's birthplace. More specifically, in ecology philopatry is the behaviour of elder offspring sharing the parental burden in the upbringing of their siblings, a classic example of kin selection...
, which means that it returns to the same area year after year, and it usually prefers the same habitat type as the original one. 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.
Feeding preferences
The ornate box turtle is an omnivoreOmnivore
Omnivores are species that eat both plants and animals as their primary food source...
, with no particular dietary preferences; as an opportunistic feeder, it eats whatever is available in any given location or season. Grasses, berries, insect
Insect
Insects are a class of living creatures within the arthropods that have a chitinous exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae...
s and other invertebrate
Invertebrate
An invertebrate is an animal without a backbone. The group includes 97% of all animal species – all animals except those in the chordate subphylum Vertebrata .Invertebrates form a paraphyletic group...
s (caterpillar
Caterpillar
Caterpillars are the larval form of members of the order Lepidoptera . They are mostly herbivorous in food habit, although some species are insectivorous. Caterpillars are voracious feeders and many of them are considered to be pests in agriculture...
s, grasshopper
Grasshopper
The grasshopper is an insect of the suborder Caelifera in the order Orthoptera. To distinguish it from bush crickets or katydids, it is sometimes referred to as the short-horned grasshopper...
s, beetle
Beetle
Coleoptera is an order of insects commonly called beetles. The word "coleoptera" is from the Greek , koleos, "sheath"; and , pteron, "wing", thus "sheathed wing". Coleoptera contains more species than any other order, constituting almost 25% of all known life-forms...
s, earthworm
Earthworm
Earthworm is the common name for the largest members of Oligochaeta in the phylum Annelida. In classical systems they were placed in the order Opisthopora, on the basis of the male pores opening posterior to the female pores, even though the internal male segments are anterior to the female...
s), fruits, vegetables, and carrion
Carrion
Carrion refers to the carcass of a dead animal. Carrion is an important food source for large carnivores and omnivores in most ecosystems. Examples of carrion-eaters include vultures, hawks, eagles, hyenas, Virginia Opossum, Tasmanian Devils, coyotes, Komodo dragons, and burying beetles...
(mammals, birds, amphibians, snakes, and even other turtles). This varied diet means the turtle has very little competition for available food resources.
Lifespan
The lifespan of the ornate box turtle has been reported to be from 32 to 37 years, with studies showing that males occur about half as frequently as females. The reason for the predominance of females is thought to be primarily due to temperature; incubating eggs at 29°C (84°F) produces 100% female offspring, so in the wild a combination of temperature, humidity, and other factors are thought to favor female differentiation.Birds, such as crow
Crow
Crows form the genus Corvus in the family Corvidae. Ranging in size from the relatively small pigeon-size jackdaws to the Common Raven of the Holarctic region and Thick-billed Raven of the highlands of Ethiopia, the 40 or so members of this genus occur on all temperate continents and several...
s, raptor
Bird of prey
Birds of prey are birds that hunt for food primarily on the wing, using their keen senses, especially vision. They are defined as birds that primarily hunt vertebrates, including other birds. Their talons and beaks tend to be relatively large, powerful and adapted for tearing and/or piercing flesh....
s, and raven
Raven
Raven is the common name given to several larger-bodied members of the genus Corvus—but in Europe and North America the Common Raven is normally implied...
s; domestic cat
Cat
The cat , also known as the domestic cat or housecat to distinguish it from other felids and felines, is a small, usually furry, domesticated, carnivorous mammal that is valued by humans for its companionship and for its ability to hunt vermin and household pests...
s and dog
Dog
The domestic dog is a domesticated form of the gray wolf, a member of the Canidae family of the order Carnivora. The term is used for both feral and pet varieties. The dog may have been the first animal to be domesticated, and has been the most widely kept working, hunting, and companion animal in...
s; opossums; raccoon
Raccoon
Procyon is a genus of nocturnal mammals, comprising three species commonly known as raccoons, in the family Procyonidae. The most familiar species, the common raccoon , is often known simply as "the" raccoon, as the two other raccoon species in the genus are native only to the tropics and are...
s; skunk
Skunk
Skunks are mammals best known for their ability to secrete a liquid with a strong, foul odor. General appearance varies from species to species, from black-and-white to brown or cream colored. Skunks belong to the family Mephitidae and to the order Carnivora...
s; snake
Snake
Snakes are elongate, legless, carnivorous reptiles of the suborder Serpentes that can be distinguished from legless lizards by their lack of eyelids and external ears. Like all squamates, snakes are ectothermic, amniote vertebrates covered in overlapping scales...
s; and even adult box turtles; are potential predators of young turtles. The turtle has very little means of self-defense other than closing the shell, though they may potentially bite if handled.
Until recently, there was very little scientific knowledge of diseases and parasites among the turtle populations; early studies showed that a genus of fly sometimes infested the legs of these turtles and caused death by starvation because their movement was impeded. More recently, it has been found that respiratory, metabolic, and shell diseases, common in desert tortoises, also fairly common in land turtles such as the ornate box turtle; and that nutritional deficiencies contribute to these other diseases.
The age of ornate box turtles has been estimated by counting growth rings for many years. This is similar to estimating the age of a tree but for turtles, the “rings” are lines that form on part of the shell that are like scales and the longer a turtle lives, the more rings are formed. However, using the rings to estimate age is not always reliable. The shell does increase in size as turtles get older, even though its weight makes it heavy to carry around.
Intrinsic threats – natural occurrences and factors relating to the turtle itself
Because of its late reproductive age, low reproductive rate, high young mortality, and long lifespan, the ornate box turtle is subject to pressure from intrinsic factors that limit the population growth. Young turtles are vulnerable to predation until the shell is strong enough to be a major protection (except from being run over by cars). The loss of any older females is a problem, because they don’t get replaced very fast. Climatic factors are also possible threats to the ornate box turtle. Because the sex of turtles is strongly influenced by temperature, the sex ratio can be changed by climatic extremes and result in a population that is mostly all one sex for several years in a row. This gender imbalance would affect the survival of small groups that would be threatened by the occurrence of a genetic bottleneck which means the gene pool would be too small and cause inbreeding and mortality. The bottleneck effect is a double-edged sword for species that live a long time because the loss of genetic diversity would not be as obvious or as severe, but once it occurred, it would be harder to recover. The other thing about the ornate box turtle’s life history that is a problem for its survival is its home range philopatry, which means that it returns to the same area every time and so disruptions in the area make it more vulnerable.Extrinsic threats – human effects on the Ornate Box Turtle
The ornate box turtle is a terrestrial turtle and terrestrial turtles are sensitive to human causes such as habitat destruction, introduced species, harvest or collection, pollution, and climate change.Agriculture – agriculture in the Great Plains has been the worst problem for the ornate box turtle recently because it has taken away lots of acres of land, destroyed habitat, caused more traffic, and created small, isolated areas of prairie. In addition, the small pieces of prairie mean more edge habitats, which causes more predators to live there and that increases predation of the box turtle that is already suffering from less total habitat area. Other agricultural factors that are a problem for the ornate box turtle are fences, water troughs, cattle (trampling), mowing, and other machinery.
Development – houses and other building construction causes loss of habitat similar to agriculture, but also increased removal for pets, predation by dogs, and greater predation to crows and raccoons that increase around human living areas. Where housing developments are built, there are also more roads. The box turtle feeds on carrion when it is available and on roads road-kill is a large source of carrion and a large cause of death of ornate box turtles.
Over-exploitation – a huge number of ornate box turtles have been collected for sale in pet stores, and individuals have always collected some turtles. The commercial trade has had a large effect on the Great Plains populations and if it continues, the result will be a serious decline in turtles.
Conservation efforts
According to the International Union for Conservation of Nature, the ornate box turtle is "near threatened." In some states, such as Nebraska, Kansas, and Colorado, the turtle is "secure"; but in South Dakota, it is listed as “imperiled”; and in Wyoming it is listed as "critically imperiled." Management decisions for the ornate box turtle are difficult because of life history factors. It seems that the best strategies will be aimed at older females to increase their survival instead of concentrating on hatchlings and juvenile turtles. One of the first things that needs to be done is to get a better idea of the actual number of ornate box turtles that exist and also to make it illegal to collect any for pet or commercial trade, as some states did. Along with this is the need to stop the release of captive box turtles that have respiratory infections into the wild because of the effect of disease on survival. Management techniques that preserve the best habitat composition are important conservation practices.Probably the biggest factor that affects the ornate box turtle is interactions with human so any action that minimizes contact is helpful. Working to keep large areas of habitat undisturbed is also helpful. Managing weeds with a minimal amount of herbicide and knowing what chemicals are in the herbicide and how they affect turtles is important. The use of fire and mowing to control weeds should be done carefully when turtles are inactive or in burrows to keep cool. The public is not likely to want to stop collecting turtles, even if the pet trade were prohibited, because people like to look at turtles and other forms of nature. Nebraska and Louisiana have prohibited collecting ornate box turtles, but New Mexico and Texas have not.
Educating the public about the risks to the ornate box turtle will be difficult but should be part of the conservation effort. One conservation effort that might be helpful is removal of predators from an area where many turtles are found; one study found that removing raccoons was helpful but it also leads to the question of balance in nature and which animals are more important. Some biologists have suggested that moving turtles from healthy populations to areas where the turtle is struggling might be an option but this is difficult and might be a last resort.
Habitat loss is the biggest problem for the ornate box turtle and isolated habitat areas have isolated groups of turtles that lose genetic diversity and experience bottlenecks that decrease their survival.
Because the ornate box turtle has a long life-span and doesn’t reproduce until late, it will be difficult to manage conservation of this turtle.