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Turtles have long been used as symbols in human culture. Characteristics such as wisdom, support, wealth, strength, felicity and longevity are often associated with turtles. They have played roles in religion in cultures from the Cheyenne Indians to Hinduism. In some religions, turtles carry the earth or hold up the sky. Turtles are usually considered to be beneficial creatures but this doesn't bring out a caring for their welfare. Turtles may symbolize longevity, but it doesn't benefit them. In some cultures, eating them allows for a longer life. Many turtle species suffer in the hands of man. They are often sold in live animal markets as food or used in traditional medicine. Turtle parts are used in remedies ranging from improving sexual performance to lowering high blood pressure (Moll & Moll 2004). As native turtle populations sink, some Asian countries are importing turtles from other parts of the world. Some of these imported turtles include Red-eared Sliders (Trachemys scripta elegans), which can become invasive species when they escape or are let go in their new surroundings. Red-eared Sliders are very invasive, they are fast reproducers, and are usually more aggressive than native turtle species. They just simply out-compete native turtle species. Red-ears are on the World Conservation Union's list of worst 100 invaders. Cartoon turtles are common in entertainment and children's literature, such as the Teenage Mutant Ninja Turtles, Alice's Adventures in Wonderland's Monk Turtle, The tortoise & the Hare and Yertle the Turtle.
For most people, there are turtles and tortoises but for turtle taxonomy the first division is how they stick their necks into their shells. Most turtles (Cryptodira: ~211 species) simply retract their necks straight back into their shells, but some turtles (Pleurodira: ~74 species) have to fold their necks to the front part of their body to get it under the protection of their shells. The sub-order Pleurodira consists of three families and contains species such as South American Snake-necked Turtle (Hydromedusa tectifera), Yellow-spotted Amazon River Turtle (Podocnemis unifilis), Northern Australian Snapping Turtle (Elseya dentata) and East African Black Mud Turtle (Pelusios subniger). The sub-order Crytodira contains nine families and contains species such as Colombian Wood Turtles (Rhinoclemmys melanosterna), Alabama Red-bellied Turtle (Pseudemys alabamensis), Hermann's Tortoise (Testudo hermanni), Common Snapping Turtle (Chelydra serpentina) and Wattle-necked Softshell Turtle (Palea steindachneri). Both sub-orders have some similar common names such as East African Black Mud Turtle (Pleurodira subniger) and Yellow Mud Turtle (Kinosternon flavescens), but in no way does that apply that they are closely related. In fact, Yellow Mud Turtles are more closely related to Sea Turtles than they are to the East African Black Mud Turtles, even through both species are very similar to each other.
Turtles can be found on every continent except Antarctica; they live in habitats from the cold North Sea to some of the driest upland deserts. They have been around for over 200 million years, and have changed very little. They all have shells, but shells can vary from skin & flesh to an almost rock hard plate. Some shells are almost pancake flat while others are domed in shape. Their body weight ranges from 5 ounces to over 1,600 pounds. Softshell turtles have body designs that are geared for fast locomotion in water, while Leatherbacks have large body sizes and insulation that enables them to keep warm in cold oceans.
The anatomy of turtles differ from elephantine hind feet of tortoises to flat paddle shaped feet of aquatic turtles. Their head shapes can vary from the pointed head of a softshell turtle to a broad & flat head of a Mata mata turtle. Shell shape vary from a leathery steamline shape of River Fly Turtles to hard dome shaped shells of land tortoises.
Out of the eight thousand species of reptiles worldwide, turtles are probably the only reptile group that most people like or don't have a negative opinion of. Very few people dislike turtles. Sea turtles in particular are considered charismatic mega fauna and have been called the symbol of marine conservation. However, that hasn't made life easy for turtles. According to some turtle conservation groups, 66% of all turtles & tortoises are threatened with extinction. In 2003, the Turtle Conservation Fund (TCF) published a list and action plan for the top 25 most endangered turtles (tortoises & freshwater turtles only), two native species (Bog Turtles & Yellow-blotched map turtles) are on that list. Turtles are threatened by many of the same theats that other wildlife face, such as habitat loss, the pet trade, pollution, human consumption (for food & medicine) and introduction of invasive species. To learn more about Turtle Conservation, click here.
We have all heard and tried to answer the question: Why does the chicken cross the road? Have you ever asked yourself why turtles cross the road? For most of the year, turtles cross roads to they can reach the other areas of their fragmented habitat. Reasons for movement could be in search of mates, looking to food sources, moving from one habitat to another, and traveling to food & den sites. Many land turtles travel wide distances, so it is fairly often that they could be seen crossing roads. For example Ornate Box turtles have home ranges from 5 to 143 acres (Redder, Dodds & Keinath 2006). In some parts of the U.S., family activities such as going out looking for "spinning turtles" in the country side are not uncommon. These are usually box turtles that were blown upside down by drafts from cars, and are found upside down on roads. However, these events are getting rarer as over collecting and high adult mortality starts to affect turtle populations.
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