Anacondas and pythons are two of the world’s most formidable snake groups, captivating human interest with their immense sizes. A common question arises: which of these colossal constrictors is truly the largest? The answer depends on whether length or weight defines “biggest,” highlighting the nuances in comparing these reptilian giants.
Unveiling the Anaconda’s Size
The Green Anaconda (Eunectes murinus and Eunectes akayima) is the world’s heaviest snake. Adult female green anacondas typically average around 4.6 meters (15 feet) in length, though mature specimens can reach up to 5 meters (16.5 feet). Their weight commonly ranges from 30 to 80 kilograms (66 to 176 pounds).
Verified records include a female measuring 5.21 meters (17 feet 1 inch) and weighing 97.5 kilograms (214 pounds). Another notable specimen at the Pittsburgh Zoo reached 6.27 meters (20 feet 7 inches) and weighed 91 kilograms (200 pounds). While unconfirmed reports suggest lengths up to 9 meters (30 feet) and weights over 250 kilograms (550 pounds), a Northern Green Anaconda identified in 2024 was confirmed at 6.3 meters (20.7 feet) and estimated to weigh over 200 kilograms (441 pounds). Anacondas are known for their massive bulk and considerable girth.
Exploring the Python’s Dimensions
The Reticulated Python (Malayopython reticulatus) is the world’s longest snake. These serpents commonly grow between 3 to 6 meters (10 to 20 feet). Historical records claim exceptional individuals reached up to 10 meters (32.8 feet), though experts suggest a more probable maximum length is around 8 to 9 meters (26 to 29.5 feet).
The longest reticulated python in captivity, Medusa, measured 7.67 meters (25 feet 2 inches) and weighed 158.8 kilograms (350 pounds). The Burmese Python (Python bivittatus) also reaches significant sizes, with adults typically 3 to 5 meters (10 to 16 feet). Confirmed specimens have reached 5.8 meters (19 feet) and weighed 97.5 kilograms (215 pounds). While pythons can surpass anacondas in length, they generally do not match them in overall weight or girth.
The Verdict: Which Snake Reigns Supreme in Size?
When comparing the largest snakes, the definition of “bigger” is important, as it can refer to either length or mass. The Reticulated Python is the world’s longest snake. Conversely, the Green Anaconda is the heaviest and most massive snake.
This distinction highlights their different body compositions. A 5.2-meter (17-foot 1 inch) Green Anaconda possesses a bulk comparable to a 7.4-meter (24-foot 3 inches) Reticulated Python. Anacondas are notably thicker and more robust for their length compared to the more slender build of pythons. While a Reticulated Python may stretch further end-to-end, a Green Anaconda will generally outweigh it considerably, making the anaconda supreme in terms of mass and girth.
Beyond Size: Other Key Differences
Beyond their dimensions, anacondas and pythons exhibit distinguishing characteristics, including geographic ranges, habitats, and reproductive strategies. Anacondas are native to tropical South America, primarily inhabiting areas east of the Andes, such as the Orinoco and Amazon river basins. They are found in Colombia, Venezuela, Brazil, Ecuador, Peru, Bolivia, the Guianas, and Trinidad.
Pythons are found across the Old World tropics, distributed throughout sub-Saharan Africa, Asia (including India, Southeast Asia, China, and the Philippines), and Australia. Anacondas are semi-aquatic, spending most of their lives in shallow, slow-moving waters like swamps, marshes, and rivers, with eyes and nostrils positioned on top of their heads for submerged waiting. They are less agile on land. Pythons are generally more terrestrial or arboreal, adapting to diverse environments such as rainforests, grasslands, woodlands, and rocky outcrops.
Their reproductive methods also vary. Anacondas are ovoviviparous, giving birth to live young after eggs hatch internally. Pythons are oviparous, laying eggs that the female typically coils around and incubates until they hatch.