Python regius
Ball Python, Royal Python

Ball pythons (Python regius), also known as royal pythons, are found in the grasslands and open forests of West and Central Africa. They are native to the Sudanese subprovince west of the Nile, in southern Sudan, the Bahrel Ghazal and Nuba Mountains Region, from Senegal to Sierra Leone in West Africa, and in the Ivory Coast and some parts of Central Africa. (De Vosjoli, et al., 1995; Sillman, et al., 1999)

Ball pythons spend most of their time on or under the ground in burrows. They are most active at dawn and dusk. They inhabit savanna grasslands or open forests and are found in areas that have been cleared for farming. (De Vosjoli, et al., 1995)

At birth, ball pythons range from 25 to 43 centimeters in length and grow to 1 to 1.5 meters as adults. There are some reports of ball pythons found in the wild at 1.83 meters in length. Their heads are larger than their relatively slender necks and they are considered heavy-bodied. The typical ball python has large brown markings with lighter medium-brown spots interspersed between the darker spots. They may also have yellow stripes from the nostrils through the eyes. The belly is generally ivory white. Adult female ball pythons are larger than adult males. This sexual dimorphism is not present in neonates, but is apparent in adults. Adult females also have longer jaws than their male counterparts. The resultant increase in swallowing capacity may improve their hunting ability. (Aubret, et al., 2005; Barker and Barker, 2006; De Vosjoli, et al., 1995)

Ball python hatchlings range from 25 to 43 centimeters; adults from 0.9 to 1.5 meters. The gestation period is about 44 to 54 days. Most ball pythons lay their eggs during the second half of the dry season, from mid-February to the beginning of April. Eggs are then hatched from mid-April to mid June. Approximately 3 weeks after ovulation, a female ball python begins to shed its skin. Eggs are laid about 4 weeks later. (De Vosjoli, et al., 1995)

After laying their clutch of eggs, female ball pythons coil around their clutches until hatched (after approximately 2 months). Hatchlings are immediately independent, but remain in the vicinity for months after. (Aubret, et al., 2002)

Ball pythons have long reproductive lives that last from about 27 months to 30 years. The breeding season is primarily from mid-September through mid-November, correlating with the minor rainy season. A clutch is from 1 to 11 eggs. The eggs typically adhere to each other. A few days before hatching they lose their adhesion. After the eggs are no longer attached and are ready to hatch, baby ball pythons slit the shells with their egg tooth and work their way out. Weight at birth is 65 to 103 grams, with an average of 86 grams. Female ball pythons reach reproductive maturity from 27 to 31 months. Males reach reproductive maturity at 16 to 18 months. Both male and female ball pythons have large cloacal spurs.

Humans can determine python sex by placing a probe through the cloacal spur and into the inverted hemipenis. The probe will travel deeper into the base of the tail for male ball pythons, spanning 8 to 10 subcaudal scales in contrast to females in which the probe may be only inserted a distance of 2 to 4 subcaudal scales. (De Vosjoli, et al., 1995)

Once female ball pythons lay their eggs, they consistently ball around the eggs for protection. Ball pythons also stay in close proximity to eggs to protect them from predators. (Ellis and Chappell, 1986)

The average lifespan of ball pythons in captivity is 20 years. Reports document the maximum lifespan in captivity ranges from 28 years (at the Oakland Zoo) up to 50 years (reported by the Philadelphia Zoo). Average life span in the wild is reported to be 10 years. (Gorzula, et al., 1997; Bartlett and Bartlett, 2000; Bartlett, et al., 2001; Gorzula, et al., 1997)

Ball pythons move by way of rectilinear locomotion, whereby bilateral symmetrical contractions propel them forward as they push against the surface. Ball pythons are known for the protective mechanism of “balling,” where they form a tight ball with the head at the center in response to threats, earning them their common name, "ball python." (Bustard, 1969; De Vosjoli, et al., 1995; Greene, 1997; McDonald, 1996; Sillman, et al., 1999)

Vision plays an important role in a ball python’s ability to secure prey. Research on the way these snakes behaved under bright light determined that ultraviolet activity may be a factor in capturing prey. Other research suggests that ball pythons may follow the scent trails of their mammalian prey because those trails reflect ultraviolet light. (McDonald, 1996; Sillman, et al., 1999)

Ball pythons are carnivorous and have mobile lower and upper jaws. They use chemical and visual cues to hunt for their prey. Ball pythons sit and wait to ambush prey. As heavy-bodied snakes, they are less active and instead choose good ambush sites. The feeding strategy is to retract the head and neck and strike rapidly. After the rapid strike, they swallow prey alive or immobilize by constriction. They feed almost exclusively on rodents and eat infrequently. Infrequent feeders have adapted by having the capacity to widely regulate gastrointestinal functioning with feeding and fasting. Ball pythons prey on rodents and are vital to controlling these pests, especially in rural communities. Rodent prey includes African giant rats (Cricetomys gambianus), black rats (Rattus rattus), rufous-nosed rats (Oenomys species), shaggy rats (Dasymys species), and grass mice (Lemniscomys species). (Greene, 1997; Ott and Secor, 2007)

Ball pythons attempt to avoid detection by predators and to seek cover. Defenses include camouflage, escape attempts, bluffing displays, and biting. Ball pythons are best known for “balling,” in which they form a tight ball with the head at the center. There are few known predators of adults, although the trappers of Ghana have reported that black cobras (Naja nigricollis) prey on small and medium pythons. Some known predators, especially of young pythons, include humans (Homo sapiens), carnivorous mammals, and birds of prey. (Greene, 1997)

Ball pythons are found in western to central Africa, just north of the equator. They are found in grasslands and open forests, and in areas with some cover. They are typically found near open water so they can cool themselves during hot weather. They spend most of their time on or in burrows under the ground, although they are able to climb. They are primarily nocturnal and active during the wet season. Bush fires can also affect ball pythons. In addition, farmers may kill ball pythons out of fear.

Ticks are primary parasites, with a slightly higher tick burden in males than females. This may be due to the prolonged periods of immobility in females during the two months of brooding their clutch. Male movement to capitalize on encounters with females may increase their risk of exposure to ticks. There are also internal parasites found in ball pythons including, Trypanosoma varani, Helpatozoon (Apicomplexa: Adelorina), and Spinicauda regiensis. (Aubret, et al., 2005; De Vosjoli, et al., 1995; Gorzula, et al., 1997; Mukhtar, et al., 2009; Platt and Bush, 1979; Sloboda, et al., 2007)

The economic importance of ball pythons to rural communities of central and western Afria is the control of rodents. The magnitude of this benefit is in the millions of dollars per year. Even though ball pythons are exported, there is little direct economic benefit to rural communities except the economic impact of providing lodging and food for trappers. There are some areas where ball pythons are considered sacred and are fully protected. In these areas there seems to be an awareness of the benefits of these pythons. Although ball pythons can be bred in captivity, most are imported from Africa. Approximately 30,000 to 50,000 ball pythons are exported annually to America, mostly as hatchlings from wild pythons. Ball pythons are easily handled snakes, which is what makes them good pets. Trappers of ball pythons tend to be economically vulnerable, which drives them towards trapping these snakes for export. Ball pythons are also occasionally eaten. (Aubret, et al., 2005; Bartlett and Bartlett, 2000; De Vosjoli, et al., 1995; Gorzula, et al., 1997)

There are few negative effects of ball pythons on humans, as these snakes do not tend to be aggressive. (De Vosjoli, et al., 1995; Gorzula, et al., 1997)

Because of their large range and high, stable population numbers, ball pythons are not considered threatened currently. A change to highly mechanized farming and substantial use of agrochemicals may change survival rates of ball pythons, affecting populations. (Gorzula, et al., 1997)