Seed dispersal by reptiles has received little attention from researchers. Liu et al. (2004) studied seed dispersal by the Florida Box Turtle (Terrapene carolina bauri) in pine rockland forests in Key Deer National Wildlife Refuge (KDNWR) on Big Pine Key in the lower Florida Keys (U.S.A.). Examining the feces of 145 box turtles from KDNWR in 1999 and 2000, they found that the bulk of the diet consisted of fleshy fruits and terrestrial snails. The seeds of fleshy-fruited plants and snail remains were present in the feces of 138 (95.1%) and 128 (88.2%) turtles, respectively. Leafy vegetation occurred in the feces of 33 (22.7%) turtles, while insects, fungi, and vertebrate remains (most likely consumed as carrion) were each found in the feces of 10 (6.8%) or fewer turtles.
In their study, Liu et al. found that box turtles consumed and probably dispersed at least a third of the species with fleshy fruits that occur in pine rockland forests of KDNWR, including dominant components of the shrub layer (Byrsonima lucida, Thrinax morrissii, Serenoa repens, Coccothrinax argentata) and herbaceous (Morinda royoc) layer (in addition to seeds from 11 fleshy-fruited plant species, seeds were found in turtle feces from a grass, Paspalum, and a legume. The researchers planted the seeds of nine species and found that germination percentage (percentage of seeds that germinated during the experiment) varied from 10% to 80%. Comparative germination experiments were conducted with Thrinax morrissii, Serenoa repens, and Byrsonima lucida. The authors compared the germination percentage and germination rate (number of days from planting to seedling emergence) of seeds from three treatments (seeds recovered from feces, control seeds with pulp, and control seeds without pulp) and continued these experiments for up to 2 years. Passage through the box turtle digestive tract greatly enhanced the germination percentage and germination rate of S. repens, but decreased the germination percentage of B. lucida and T. morrissii and decreased the germination rate for T. morrissii. Subsequent destructive seed viability tests revealed that many ungerminated T. morrissii seeds remained viable, suggesting long-term seed dormancy may occur, even after passage through the turtle digestive system. In addition, the proportion of ungerminated seeds which remained viable was greater for seeds recovered from turtle feces than from control seeds with pulp. Removal of fleshy pulp either manually or by the turtle digestive system may allow T. morrissii to escape insect predation. (Liu et al. 2004)
Box turtles may be significant seed dispersal agents in the pine rockland forests of the Florida Keys as they occur at high densities (up to 14.9 turtles per hectare on other islands in south Florida) and the pool of potential bird and mammal seed dispersers is less diverse relative to the Florida mainland. Furthermore, seeds require from 2 to 20 days to pass through the digestive tract, during which time turtles can move several hundred meters within a home range as large as 5 hectares. (Liu et al. 1994 and references therein)
The Florida Box Turtle (Terrapene carolina bauri) is a subspecies of the Eastern Box Turtle. It occurs in both the Florida Peninsula and the Florida Keys (U.S.A.) and intergrades with (blends into) other subspecies of Eastern Box Tutle where they come into contact in the northernmost part of the Florida Box Turtle's range. (Conant and Collins 1991)
Ernst et al. (1998) studied growth rates in Florida Box Turtles (Terrapene carolina bauri). They found that male Florida box turtles grow proportionally longer (relative to their height and width) than do females, resulting in a longer, flatter carapace, whereas females develop shorter, higher, and slightly narrower carapaces, possibly as an adaptation to accommodate hard-shelled eggs before oviposition. The subspecies has a typical growth pattern for a North American emydine turtle. Growth is rapid in juveniles, but starts to slow once maturity is reached at an age of 12 to 13 years. Growth rates approach an asymptote at about age 17 years in males and 16 years in females; very little growth occurs after 20 years. Florida Box Turtles (T. c. bauri) from Florida apparently grow at a slower annual rate than do Eastern Box Turtles (T. c. carolina) from Maryland despite having a longer annual activity and growth period. The cervical scute and all vertebral scutes have a greater width:length ratio in juveniles, but this ratio declines as the scutes lengthen with elongation of the carapace; however, the rare of increase in length varies among the scutes. (Ernst et al. 1998)
The Florida Box Turtle (Terrapene carolina bauri) is found throughout most of the Florida Peninsula and the Florida Keys (Verdon and Donnelly 2005 and references therein).
Box turtles are relatively sedentary, with low fecundity and high adult survivorship, delayed sexual maturity (in Florida, males reach maturity at 5-6 years and females at 7-8 years), low nest and hatchling survival, and a long life span (Dodd et al. 2006 and references therein).
The Florida Box Turtle (Terrapene carolina bauri) is 12.5 to 16.5 cm long (record 17.9 cm). The shell is arched, highest toward the rear. The light radiating lines on the shell may be broken or irregular, at least on some scutes (shell segments). There are two yellow stripes on the head, which also may be interrupted or incomplete. There are usually 3 toes on each hind foot. The plastron (lower shell) of males is deeply concave. Young Florida Box Turtles have a yellow mid-dorsal stripe and a mottled pattern, yellowish or greenish on dark brown. (Conant and Collins 1991)
Verdon and Donnelly (2005) studied Florida Box Turtles on Big Pine Key in the National Key Deer Wildlife Refuge in the lower Florida Keys (U.S.A.). The population was estimated to be 7.5% juveniles, 58.75% females, and 33.75% males, resulting in a female-biased sex ratio (1 male:1.74 females). Population size was estimated to be between about 40 and 114 individuals per 6 hectares in a pine rockland forest, with an estimated density of 4.8 to 10.2 turtles per hectare.
In a study in the Florida Keys, modal clutch size (i.e., most frequent clutch size) was 2, with turtles producing between 0 and 3 clutches per year (Dodd 1997, cited in Dodd et al. 2006).
The Florida box turtle (Terrapene carolina bauri) is a subspecies of turtle belonging to the family Emydidae and is one of six extant subspecies of the common box turtle (T. carolina)[2]
The subspecific name, bauri, is in honor of German herpetologist Georg Baur.[3]
Of the four subspecies of the common box turtle, the Florida box turtle has the southernmost range. It is endemic to the U.S. state of Florida and the extreme southeastern portion of Georgia. Its distribution is widespread throughout Florida's mainland and has also been observed in the Florida Keys and the barrier islands in the Gulf of Mexico off of Florida's western coast.[2]
The Florida box turtle can be found in damp environments such as wetlands, marshlands, and near swamps but usually does not enter water deep enough to swim.[4] It is often found in the flatwoods, upland, and mesophytic hammock but is generally absent in the high pine.[5] Within these habitats, juveniles prefer areas that contain dense cover, high amounts of leaf litter, and moist soil. Adults are more flexible in their habitat requirements and have been observed in more open areas.[6]
Like other box turtles, the Florida box turtle has a narrow and highly domed shell with a hinged plastron that allows it to close its shell tightly. However, the Florida box turtle is different in appearance from the other subspecies of Terrapene carolina. Its carapace has a distinct pattern of yellow stripes that make it easily identifiable. The coloring of the plastron can vary anywhere from solid yellow to solid black, with any number of variations in between. This turtle has sharp claws as well as a sharp beak used for catching small insects and eating fruits, vegetables, and fungi.[7]
The Florida box turtle exhibits significant sexual dimorphism. On average, males are larger (length and width) than females. The carapace length of females ranges from 12.1 - 15.8 cm while the average male carapace can be anywhere from 12.8 - 17.3 cm long. However, female carapaces tend to be taller than those of males. This is most likely to allow more space to accommodate eggs inside the body cavity.[8][9]
Like many other box turtle species, the Florida box turtle spends an extreme majority of its life (80-90%) buried in the underbrush or underground, and their activity varies significantly at different times of the year. During the dry, cool parts of the year (November - February) they enter a dormant stage and are inactive and difficult to find. They exhibit higher levels of activity during the warm, wet months (April - October).[8] However, unlike other species of box turtle, the Florida box turtle does not actually enter a complete state of brumation during this time of year. This is most likely due to the warm and stable temperatures throughout its Florida range. As a result, it exhibits longer annual activity than other box turtle species.[9] It is less tolerant to colder conditions than other common box turtle subspecies.[10]
The Florida box turtle is a generalist omnivore with a diet similar to other box turtle subspecies. Its most common food sources include gastropod species and fleshy, low-hanging fruits. They also consume leafy vegetation (shrubs, herb, grasses, etc.), insects, crustaceans, and fungi. They have even been observed feeding on carrion and garbage.[5][11][12]
The Florida box turtle contributes to the seed dispersal of various plants throughout its range. The vast majority of these plants contain fruit (Annona glabra, Brysonima lucida, Coccoloba uvifera, Cocothrinax argentata, Ficus sp., Morinda royoc, Manilkara zapoda, Psidium longipes, Serenoa repens, Smilax havenensis, Thrinax morrissii) while others might not (Paspalum spp., Fabaceae).[11]
The Florida box turtle reaches sexual maturity around 12–13 years of age.[9] While some species can produce only one clutch in a breeding season, the Florida box turtle has been observed laying as many as four separate clutches in a single year. The egg laying season occurs in the Spring and generally lasts from April to early June. On average, each clutch can contain 1 - 9 eggs that range in size from 35×19 mm to 38.5×21 mm. Its eggs tend to be slightly larger than those of other T. carolina subspecies.[10] Researchers have observed a positive relationship between female carapace length and clutch size, with larger females possessing the ability to produce more eggs. Incubation of the eggs lasts an average of 60 days but can last anywhere from 45 – 120 days. Different environmental factors may influence the reproductive success of the Florida box turtle. Years with higher levels of precipitation may positively influence reproductive success, resulting in a higher number of hatchlings when compared with drier years.[5][13] Research also points toward a positive correlation between latitude and clutch size in box turtles, with larger clutch sizes being found in higher latitudes.[14] The incubation temperature of a clutch has been observed to influence the sex ratio of the hatchlings. Warm incubation temperatures tend to produce more females, while cooler temperatures result in more males.[15]
Its growth patterns are similar to other species of box turtles. Juvenile turtles have shorter and wider scutes and carapaces when compared to adults, but these lengthen as the individual grows. Growth rates are rapid in juveniles, slow down significantly following sexual maturity, and eventually level off completely a few years later (around 16 and 17 years in females and males respectively). Despite having higher activity levels, the Florida box turtle has a slower annual growth rate than other box turtle species.[9]
Like other subspecies of T. carolina, the Florida box turtles is listed on the IUCN red list as a vulnerable species. Wild populations are at risk due to predation of eggs and juveniles (raccoons, possums, foxes, birds), habitat loss and modification, car strikes, pesticides, pollution, and collection for the pet trade and turtle racing.[16]
Seasonal fire regimes in Florida represent a significant source of mortality for box turtles, with burns having the potential to kill off nearly half of a population. However, the mortality rate of turtles is lower during dry season burns as opposed to wet season burns. This is potentially due to its inactivity and its tendency to spend more time underground during the dry season.[17]
Florida box turtles can be kept as pets. They are omnivores and feed on a huge variety of food in the wild. In captivity, they are especially fond of live food such as earthworms, crickets, locusts, snails, wax worms (as a treat because of their high fat content), superworms (Zophobas morio), and baby mice. In addition to this large variety of live foods, you can offer chopped fruits and vegetables. Finely grated dark green veggies such as lettuces and kale, and fruits such as melons, berries and cantaloupe are also accepted (though not eagerly) once or twice a week.
By law, in their home state, no person may possess more than two of these turtles. People may be prosecuted by fine and removal of the animals if they own three or more without a reptile permit.[18] This subspecies is found only in Florida, and is also protected in many other areas. Many pet stores offer hatchlings as pets, which are usually healthier than the box turtles from the wild.
{{cite journal}}: Cite journal requires |journal= (help) The Florida box turtle (Terrapene carolina bauri) is a subspecies of turtle belonging to the family Emydidae and is one of six extant subspecies of the common box turtle (T. carolina)
