vertical, and mate with the female. Remarkably, female common box turtles can store sperm for up to four years after mating, and thus do not need to mate each year. In May, June or July, females normally lay a clutch of 1 to 11 eggs into a flask-shaped nest excavated in a patch of sandy or loamy soil. After 70 to 80 days of incubation, the eggs hatch, and the small hatchlings emerge from the nest in late summer. In the northern parts of its range, the common box turtle may enter hibernation in October or November. They burrow into loose soil, sand, vegetable matter, or mud at the bottom of streams and pools, or they may use a mammal burrow, and will remain in their chosen shelter until the cold winter has passed. The common box turtle has been known to attain the greatest lifespan of any vertebrate outside of the tortoises. One specimen lived to be at least 138 years of age. Human interaction Conservation Although the common box turtle has a wide range and was once considered common, many populations are in decline as a result of a number of diverse threats. Agricultural and urban development is destroying habitat, while human fire management is degrading it. Development brings with it an additional threat in the form of increased infrastructure, as common box turtles are frequently killed on roads and highways. Collection for the international pet trade may also impact populations in some areas. The life history characteristics of the common box turtle (long lifespan and slow reproductive rate) make it particularly vulnerable to such threats. The common box turtle is therefore classified as a vulnerable species on the IUCN Red List. The common box turtle is also listed on Appendix II of the Convention on International Trade in Endangered Species (CITES), meaning that international trade in this species should be carefully monitored to ensure it is compatible with the species' survival. In addition, many U.S. states now regulate or prohibit the taking of this species. NatureServe considers it Secure. This species also occurs in a number of protected areas, some of which are large enough to protect populations from the threat of development, while it may also occur in the Sierra del Abra Tanchipa Biosphere Reserve, Mexico. Conservation recommendations for the common box turtle include establishing management practices during urban developments that are sympathic to this species,