Breeding Box Turtles: Can Eastern And Desert Species Mix?

The eastern box turtle and the desert box turtle are two different species of turtles. The former is a subspecies of the common box turtle and is native to the eastern United States, while the latter is a subspecies of the western box turtle and is found in the southwestern United States and northern Mexico. Given their different geographic locations and the fact that they belong to different species, it is unlikely that these two turtles would breed with each other. However, it is important to note that captive breeding of turtles does occur, and it is possible that humans could attempt to breed these two species together. Nonetheless, in the wild, it is expected that they would only breed within their own species.

Differences in mating seasons

The mating seasons of the eastern box turtle and the desert box turtle differ in several ways. Firstly, the desert box turtle's breeding season is influenced by the air temperature and typically lasts from March to May, while the eastern box turtle's mating season begins in the spring and continues through the summer or fall.

Secondly, the nesting seasons of these two species also vary. The desert box turtle chooses its nesting sites from May to July, whereas the eastern box turtle's nesting season is from May to June.

Thirdly, the male desert box turtles start searching for females after emerging from hibernation, and they aggressively compete for mates. In contrast, eastern box turtle males become particularly active in their female search after rainfall. While male desert box turtles remain sexually active until September or October, eastern box turtle males may mate with multiple females or the same female over several years.

Lastly, the female desert box turtles' egg production is influenced by the spring precipitation, with wetter springs leading to increased egg production. The mean number of eggs in a clutch ranges from 2.67 to 3.55. On the other hand, eastern box turtle females typically lay four to five eggs per clutch, but the number can vary from one to eleven. Additionally, female eastern box turtles can store sperm for up to four years and may lay fertile eggs for several years after a successful mating.

Differences in hibernation patterns

The eastern box turtle and the desert box turtle have different hibernation patterns.

Eastern box turtles, found in the eastern United States, from Maine to Florida, and west to the Great Lakes region and Texas, adjust their activity to maintain their optimal body temperature. In the northern regions where it gets too cold, they find a comfortable place where they can be somewhat insulated, called a hibernaculum, and will become lethargic, entering a hibernation-like state known as brumation. This begins in October or November and ends in April when they emerge again.

On the other hand, desert box turtles, found in the southwestern United States and northern Mexico, hibernate in the winter and are naturally freeze-tolerant. They are greatly affected by air temperature and weather. As soon as November hits, they begin to hibernate, and this lasts until late May or early June. They usually hibernate at temperatures between 1 and 15 degrees Celsius. They have designated overwintering or hibernation sites within their home range. The desert box turtles burrow themselves about 35 cm into the ground, with their hind limbs sticking out. They remain burrowed until the temperature increases, and factors like ground temperature, precipitation, and moisture are present. They attain a 5-month dormancy until they emerge and become active again.

Both species of turtles prepare their bodies for hibernation by eating less and resting more in late summer or early fall.

It is important to note that only healthy, adult box turtles that have gained weight during the summer should hibernate. Young, sick, or underweight box turtles should not hibernate as they may not have the necessary reserves to survive.

Differences in male characteristics

Male Eastern box turtles have red eyes, while female Eastern box turtles have brown eyes. Male Eastern box turtles are often more brightly and distinctively coloured than their female counterparts. Male Eastern box turtles have a concave plastron (the underside of the shell), while female Eastern box turtles have a flat plastron. Male Eastern box turtles have longer, thicker tails than females, and their vent (opening to the cloaca) is farther away from their body than the female's. Male Eastern box turtles have shorter, thicker, and more curved hind claws than females.

Male desert box turtles usually have red irises, although this is not true for all male turtles. Male desert box turtles have concave plastrons, thicker tails with the cloaca closer to the tip, and longer rear legs with larger curved claws. Male desert box turtles also sometimes have entirely green heads.

Differences in female characteristics

While there is no information on whether an eastern box turtle can breed with a desert box turtle, here is some information on the differences in female characteristics between the two species.

Eye Colour

Male eastern box turtles typically have red or orange eyes, whereas female eastern box turtles have brown or dark brown eyes. Male desert box turtles also tend to have red eyes, but there is no information on female eye colour.

Shell Colour

The eastern box turtle's shell is dark brown with yellow or orange markings. The desert box turtle's shell is brown with yellow spots and mottling on its head and legs.

Plastron Shape

The plastron is the underside of the shell. The female eastern box turtle has a flat plastron, whereas the male's is concave. The female desert box turtle's plastron is solid brown with yellow spots.

Claws

Female eastern box turtles have longer and thicker rear claws to aid in digging a nest. Male desert box turtles have longer rear claws with larger curved claws.

Tail

Male eastern box turtles have longer, thicker, and larger tails. The female desert box turtle's tail is less pronounced and shorter.

Size

The female desert box turtle is significantly longer than the male. The female eastern box turtle is larger than the male overall.

Mating Behaviour

Female eastern box turtles do not spar with other turtles but are skilled at building nests. There is no information on female desert box turtle mating behaviour.

Differences in habitat

The desert box turtle, or Sonoran box turtle, is a subspecies of box turtle native to arid regions in the southwestern United States and northern Mexico. They are generally terrestrial and are known to inhabit desert grasslands, shrublands, and prairies. They prefer small, defined areas where they can easily access food, shelter, and overwintering sites. Desert box turtles have a strong affinity for the area of their hatching and exhibit high site fidelity.

In contrast, the eastern box turtle is found in the eastern half of the United States, ranging from Maine to Florida and west to the Great Lakes region and Texas. They are often found near ponds, fields, meadows, and woodlands, including shrubby grasslands, marshy meadows, open woodlands, and field forest edges. Eastern box turtles are attracted to areas with abundant water sources, such as streams or areas with heavy rainfall.

One of the most notable differences between the habitats of these two subspecies is the climate and vegetation they prefer. Desert box turtles, as their name suggests, thrive in arid and semi-arid conditions, while eastern box turtles are more adaptable to a variety of habitats, including those with higher moisture levels. The colouration and markings of their shells also help them blend into their respective environments. Desert box turtles have muted colours for camouflage in the desert, while eastern box turtles have orange and yellow markings that camouflage them among damp leaves and debris in moderately moist forests.

The availability of water also plays a role in the habitat differences. Desert box turtles occasionally take to the water, while eastern box turtles are more dependent on it. Eastern box turtles are often found near water sources and spend more time in the water when they are younger, as it provides an easier hunting environment for their preferentially carnivorous diet. As they age, they shift to a more herbivorous diet and spend more time on land.

In terms of range, the desert box turtle is endemic to the southwestern United States, including west Texas, New Mexico, Arizona, and northern Mexico. On the other hand, the eastern box turtle is native to the eastern United States but has been spotted in other states due to their popularity as pets. It's important to note that releasing captive eastern box turtles into unfamiliar environments can be detrimental to their survival.

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