Individual box turtles tended to remain in small areas for long periods; these areas were interpreted as home ranges. The estimated average radius of 44 home ranges was 278 feet (average area, 5.6 acres). The average area of eight home ranges that were actually measured was five acres. General suitability of habitat and certain physical features of terrain (rock fences, ravines, barren fields) that acted as barriers were thought to be the most important factors governing size of home range. Of two turtles removed more than one-fourth of a mile from their home ranges, one homed and one did not. Home ranges of turtles of all ages and sexes overlap broadly. There was no indication that territoriality or social hierarchy existed in the population studied.
Box turtles are subject to injury from natural causes that include fire, cold, molestation by predators, and trampling by cattle. Automobiles and farm machinery now constitute major causes of mortality and serious injury. Capacity to recover after serious injury is great but there is increased chance for secondary injury, infection, and predation in the period of recovery. Pits on the shell from unknown causes ("shell pitting") are less common in ornate box turtles than in other kinds of turtles.
Ectoparasites infesting T. ornata are larvae of chigger mites (genus Trombicula) and larvae of bot flies (Sarcophaga cistudinis). Ectoparasites usually have little adverse effect on the turtles, although heavy infestations cause occasional injury or death.
Few natural enemies other than man are known; however most wild carnivores as well as opossums, large birds, and domestic dogs and cats are suspect as predators. The incidence of predation on eggs and small juveniles is far greater than on older juveniles and adults. Adults of T. ornata occasionally attack smaller individuals.
Ornate box turtles are able to detect the presence of intruders, by sight, from a distance of several hundred feet in open country; apparently, intruders are not detected until seen. Defensive behavior is passive; the shell is closed tightly in response to painful stimuli and, in some instances, at the sight of an intruder. Juveniles usually void odoriferous fluid from the musk glands when handled but adults do so only in response to pain or injury. The function of the musk glands is unknown; possibly the odor of musk is a means of sexual identification or stimulation. Although the musk is probably distasteful to predators, repellent odor alone seems to be of doubtful value as a defense mechanism.
LITERATURE CITED
Agassiz, L.
1857. Embryology of the turtle. Contributions to the natural history of the United States, 2(3):451-643, 27 pls., 12 wood-cuts in text, tables. Little, Brown and Co., Boston.
Allard, H. A.
1935. The natural history of the box turtle. Sci. Monthly, 41:325-338.