The Carpet Python (Morelia spilota) is a popular, non-venomous constrictor snake native to Australia and parts of New Guinea. This species is recognized for its impressive size and variable appearance across its wide geographic range. While all Carpet Pythons are considered medium-to-large snakes, the final size an individual reaches can vary greatly, which is a significant consideration for potential owners.
Standard Adult Dimensions
The typical adult length for a Carpet Python most commonly encountered in captivity ranges between five and seven feet. Some specimens, particularly those from the larger subspecies, can easily reach lengths of eight or nine feet, with exceptional individuals occasionally exceeding ten feet. These snakes possess a moderate girth, with adult weights typically falling between 10 and 15 pounds, though larger individuals can weigh more.
The size difference between the sexes is a notable characteristic. In many populations, the females grow significantly larger and heavier than the males, sometimes being up to four times heavier. A mature male will often be shorter and noticeably more slender than a female of the same age and subspecies.
Size Differences Among Subspecies
Carpet Pythons are a group of several subspecies, each with a distinct geographic range and size profile. This genetic variation is the primary reason for the wide-ranging size reports.
The largest of these are the Coastal Carpet Pythons (Morelia spilota mcdowelli), which are often the longest and heaviest, commonly reaching eight to ten feet in length. The Diamond Python (Morelia spilota spilota), found in cooler coastal areas, is another large type, typically growing between six and nine feet long.
In contrast, the Darwin Carpet Python (Morelia spilota variegata) and the Irian Jaya Carpet Python (Morelia spilota harrisoni) represent the smaller end of the spectrum. These subspecies often remain under five or six feet in length, which makes them highly appealing in the pet trade for keepers wanting a more manageable size. The Jungle Carpet Python (Morelia spilota cheynei) falls in the middle, typically maturing between five and seven feet.
Influences on Final Size
Beyond genetics, a snake’s final size is modulated by husbandry and environmental factors. Diet is arguably the most influential variable, as a snake’s growth is directly tied to its calorie intake. Overfeeding, especially during the snake’s juvenile phase, can lead to unnaturally rapid growth and result in an obese adult, which introduces potential health complications. The goal is to provide a consistent, moderate feeding schedule that promotes steady, healthy growth rather than maximum size.
Appropriately sized meals are recommended for optimal digestion and growth. While some people believe that a small enclosure will stunt a snake’s growth, this is a common misconception; the snake’s physiological size is determined by genetics and food intake, not the physical dimensions of its cage. Proper temperature regulation is also necessary, as an ideal thermal gradient allows the snake to digest its food efficiently, supporting its growth.
Growth Rate and Maturity Timeline
Hatchlings typically measuring between 10 and 15 inches immediately after hatching. The initial phase of life is characterized by rapid growth, especially during the first one to three years, where the snake gains the majority of its length. During this period, a weekly feeding schedule is often appropriate to support their quick development.
Growth slows considerably once the snake reaches sexual maturity, which generally occurs around three to five years of age. These snakes exhibit indeterminate growth, meaning they continue to grow throughout their entire lives, albeit at a much slower pace. The most significant increases in both length and girth are typically achieved by the time the snake is seven to ten years old. Their lifespan can exceed 20 years.