As you probably already know, we are at another mass extinction, the Holocene extinction event. Unlike the five other mass extinction events this one is mostly, if not completely caused by the age of humans (anthropogenic mass extinction). The rate of extinction has dramatically increased since the 1950's and many scientists think half of all living things could go extinct by 2100. Like all problems, solving them begins with prioritizing the list of things to do. In verterbrate conservation, scientists have made lists of verterbate orders that are in need of the greatest help. Roughly, 21% of all bird species and 50% percent of all amphibian species are at risk for extinction. The highest rate belongs to the order of Testudines (turtles)! Of the 285 species of turtles, 190 (66%) of them are threatened with extinction. The late John L. Behler says it best: "There is no vertebrate group facing greater survival problems today. Turtles saw the great dinosaurs come and go and are now facing their own extinction crisis."

Luckily for turtles, there has been a trend in wildlife laws to give protection to this order. Many states have some sort of a restriction on collecting turtles. In Wisconsin for example, non-protected turtles can only be collected from July 15 through November 30, which relieves collecting pressure during the breeding season of Wisconsin turtles. In Wisconsin, the Ornate Box Turtle, Blanding's Turtle and the Wood Turtle are protected species and can not be collected from the wild at anytime. It also sets a limit on the number and the size of turtles that can be possessed at a time. Recently, Texas & Florida passed laws that regulate the collecting of turtles for commercial uses, both setting standards for state level protection.

Turtle declines are caused by the same forces that cause declines in all wildlife. Pollution, Pet Trade, Invasive Species, Habitat Loss and Human Consumption are all things that we could stop or at least minimize by simple changes in our lives. It could be things such as buying from companies that are environmentally friendly, not buying wild caught turtles from pet stores, cleaning the bottom of boats to remove hitchhiking invasive aquatic plants, joining an organization that promotes protection of wild places and not using products made from endangered/threatened wildlife. It does not take a $5.00 gallon of organic milk to help turtles and other wildlife, but it does require some restaint and foresight from consumers.

Turtles are affected by a broad spectrum of contaminates, from chemical to thermo. A toxic cocktail of pesticides could either kill turtles directly or indirectly by killing their food supply. Nutrients from sewage and fertilizer run offs cause aquatic habitats to become eutrophic (high nutrient content) and thus change plant and animal communities faster than normal. Eutrophication can cause oxygen levels to drop thus could wipe out a lake or river's entire shellfish population. Light pollution has been well documented in hatchling sea turtles. Baby sea turtles are attracted to lights because they think it is the open sky, thus the direction of the ocean. This adds another factor that increases hatchling mortality.

Solid wastes such as discarded fishing nets and plastic bags can drown or suffocate turtles. Even when trash is properly placed in trash cans, it still attract predators such as foxes and raccoons that may also dig up turtle nest. Once pollution has started, all is not lost. Even some of the worst polluted areas can be almost restored to natural state with enough money. The Lake Erie situation in the 1960's and 1970's is a classic example. Excessive phosphorus and other pollutions caused eutrophication of the lake, and this lead to the deaths of fish and other aquatic life. The lake's beauty quickly dissolved and the odor from the lake repelled outdoorsman and home owners. The government of United States and Canada spent $7.5 billion dollars on wastewater treatment plants in 1972 and by the the 1980's the lake was becoming more ecologically sound.

Humans have had a long history of keeping turtles as pets. Children and adults from many if not all cultures are captivated by these shelled vertebrates. However, collecting for the pet trade has put a huge strain on wild populations. Turtle collectors would go out and collect hundreds of turtles and then sell them to exporters or pet shops. There are high mortality in these wild caught turtles and maybe one in twenty would end up as a pet. One particular case is the Ornate Box Turtle. This species was collected all over its range to be sold as pets in the states or overseas. In the mid 1990's, it was common to find adult box turtles for sale at pet stores for 10 to 20 dollars. Current prices for this species range from 90 to 139 dollars for adults. It may take up to 10 years for box turtles to grow to adult size. This makes the $139 dollar price tag a bargain considering the growth time (ten year old palm trees retails for $300 to $500). Removal of reproductive age turtles will decimate a population quickly, considering that very few baby turtles reach reproductive age. In a period of five and a half years, 377,534 turtles were exported out of Texas alone (Ceballos & Fitzgerald 2004). Luckily many states have laws that restrict species and numbers of turtles that may be collected. Another pet trade threatened species is the Bog Turtle. Currently the species is protected under state (Pennsylvania 1974) and federal laws (US in 1997), but due to "their small size, attrative qualities and overall rarity, these turtles are prized by both domestic and oversea collectors" (Shiels 1999). Years of trade in the black market had seriously decreased their numbers. Due to a lack of care or understanding towards reptiles, the Lacy Act had little to no affect on stopping illegal trade in this species until the federal listing under the Endangered Species Act.

Another aspect of pet trade that affects wild turtle populations is the release of pet turtles into the wild. Non-native captive turtles could be detrimental to wild species due to competition of resources. A prime example of this is the Red-eared Slider (Trachemys scripta elegans) . This species has been introduced all over the world due to the pet trade. The state of Louisiana alone produces 12 million baby Red-eared Sliders (RES) each year for export. RES are now breeding in places as far away as Australia and they have made it to Invasive Species Specialist Group's list of 100 worst Invaders. In introduced areas, RES have hybridized with Yellowbelly Sliders (Trachemys s. scripta) and Eastern Painted Turtles (Chrysemys p. picta). In California, the non-native RES are out competing the threatened (endangered in Washington, special concern in Calfornia) Western Pond Turtle (Actinemys marmorata) . Many states such as Wisconsin and Washington have RES on their invasive species watchlist. The RES pictured to the left were photographed at a fountain in Hoi An, Vietnam. The turtle swimming below them is a Vietnamese Pond Turtle (Mauremys annamensis). Not alot of research has been done on Red-eared Sliders and their impact on Vietnamese biodiversity, but if the trend is like other areas, RES can negatively affect native turtles.

The transmission of diseases from captive animals to wild animals is another concern from the pet trade. There are several documented cases where a non-native animal has transimitted a foreign pathogen to a native animal. A wild caught turtle from a different country could protentially carry a disease that native turtles have not evolved to cope with. Such a disease could wipe out an entire species or even a community of turtles. Scientists believe that wild populations of Desert Tortoises have been given Upper Respiratory Tract Infections by released captive Desert Tortoises. Another example is canine distemper being transmitted by domestic dog (virus reservoir host) to wild animals such as African Wild Dogs, African Lions, Timber Wolves and Black-footed Ferrets. More current examples of emerging diseases exacerbated by the pet trade are Ranavirus and Chytrid fungus, which are contributing to the worldwide Amphibian Decline crisis.

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