Pythons return home, slowly but surely, finds a new study

A recent telemetry study on 14 Indian rock pythons (Python molurus) in two South Indian tiger reserves has shed light on various aspects about the species, adding to the knowledge, that is currently limited, about snake ecology, distribution, population or behaviour in India, home to some of the largest snakes in the world.

The study, conducted in Sathyamangalam and Mudumalai reserves in Tamil Nadu, aimed to understand the home range of the species. Understanding the home range, determines the behavioural ecology of a species across spatiotemporal scales, notes the paper. Certain fundamental parameters such as foraging patterns, migration and dispersal, and breeding success are directly associated with animal space use.

India is home to three species of pythons — Indian rock python, Burmese python and reticulated python — considered the largest snake species in the world. While Indian python is distributed across the Indian subcontinent, Burmese python is restricted largely to Northeast India with some pocketed population reported from the north. The reticulated python, found across Southeast Asia, however, is restricted to the Nicobar archipelago in India. 

A large home range and a slow return to home 

Scientist Chinnaswamy Ramesh of Wildlife Institute of India who led the study informed Mongabay India that the research team found the pythons to have a home range of about four square kilometres. Moreover, the snakes will return home if they are released within 13 kilometres of their home range. “We found that one of the pythons took 11 months to travel 13 kilometres back to its home range but it returned nonetheless,” Ramesh said. So, the takeaway, according to Ramesh, is that a rescued python should ideally be translocated beyond 13 kilometres for it to not return.

The researchers did not observe any correlation between the body mass or the size of the individual python and its home range, unlike other large snake species, such as the king cobra. In a study conducted in Thailand, larger king cobras (Ophiophagus hannah) had larger home ranges suggesting a potential connection between size, metabolic demands and foraging effort.  

Pythons are shy, elusive snakes that steer clear of human encounters. Pythons attacking humans are largely unheard of though the size of the snake can be intimidating. They are often spotted in human-modified landscapes like farms and fields where there is prey abundance. It is important to educate agricultural communities around the python habitats about the advantage of having a large-sized medically unimportant (non-venomous to humans) snake serving as a free pest control on their farms for the better conservation of the species, according to experts like Ramesh. 

Scientist Kartik Sunagar of Centre for Ecological Sciences, Indian Institute of Science, Bengaluru said that studies like this are very important as we know very little about Indian snakes. “It’s astonishing how much we know about large mammals and so little about snakes. Understanding the home ranges of elusive animals, such as snakes, also helps in designing better conservation strategies,” he said. 

For an adult python, size doesn’t matter

The telemetry study, supported by the DST-SERB (The Department of Science and Technology – Science and Engineering Research Board), had the Tamil Nadu Forest Department and veterinary team from Sathyamangalam Tiger Reserve collaborating with the Wildlife Institute of India for transmitter implantations. Radio telemetry uses radio signals from a transmitter inserted in the snake to determine its location and track it to study the home range, behaviour, and ecology, among other things, of the snake.

Read more: Radio telemetry signals new ways to study snakes

Ramesh informed that his studies on pythons in the north (in the past) and the south of India revealed that their mating seasons differed, with the animals in the south starting to mate in January, a month earlier than the individuals in the north, maybe due to the differences in the atmospheric temperature. Differences were observed in mating aggregation too with seven to eight males mating with one female in the north while two to three males aggregating to mate with a single female in the south. Since reptiles are poikilothermic animals – organisms with variable body temperature that tends to fluctuate with temperature of its environment – it was important to understand how temperature determined their behaviour, including mating, said Ramesh.

Another crucial finding from a previous study in 2021 by Ramesh and team is the size of an adult Indian rock python. A python was earlier believed to be an adult when it had reached a significant size of about seven to eight feet but the researchers observed a male python, about six and a half feet (198 centimetres) in length, mating with larger females. This finding, according to Ramesh, could determine the conservation strategies for the species. “It is good news for India where the python population is on the decline. It would be easier to breed a smaller python in captivity,” he said. This, however, may not be the best news for the U.S. where the Burmese python, considered to be a sub-species of Indian python earlier, is having negative impacts on the local ecosystem, as an invasive species. “The genetic makeup of the Indian and Burmese pythons are not very different and they are found to interbreed, too,” said Ramesh. Experts hope that the study findings will help amp up conservation strategies on pythons whose population is reported to be on the decline. 

Watch: A radio transmitter is surgically inserted into a Russell’s viper

Banner image: An Indian rock python in a zoological garden in Stuttgart, Germany. Indian rock pythons are one of the least studied snake species. Photo by Holger Krisp/Wikimedia Commons.