I definitely chose today’s animal for its looks. I was out of the country for the past two weeks for work, and couldn’t bring much with me. So I grabbed my smallest sketchbook and brought only one pen — one of those clicky ones that has multiple colours. All I had to work with was red, green, blue and black. And so I picked a snake that was mostly green, hoping I could make some kind of passable art with the supplies I had brought.
The snake I chose to draw was the green tree python, a snake that is found in Australia, Indonesia, and New Guinea. These snakes are aptly named, as they are green and like to live in trees. They are found in tropical rainforests, generally staying at elevations between sea level and 2000m. Younger snakes tend to stay around the edges of the forest or in canopy gaps, while adults are perfectly comfortable in closed-canopy forests.
Green tree pythons can get pretty big, with the average length being 1.5 meters, though snakes of up to 2.2 meters have been recorded. They are long and thin, with a well-defined head. Green tree pythons are really beautiful snakes: they are bright green with white scales forming a patterned line down their backs. Juvenile snakes are easily distinguished from adults, as they are either bright yellow or red.
As I mentioned, green tree pythons are quite fond of trees. In fact, they are the most arboreal python in the world. Their long tails are prehensile, which helps them climb and navigate their forested habitat. Tree pythons have a very distinct resting posture, where they throw a few coils over a branch and then sit in a saddle position with their heads resting in the middle.
This is quite distinct from the pythons’ hunting posture. When green tree pythons are looking for prey, they extend the front part of the their bodies, ready to strike at any prey that wanders by. Snakes change between resting and hunting postures at dawn or dusk, to stay camouflaged.
Green tree snakes are carnivorous, feeding on small reptiles, amphibians and mammals. They kill their prey by constriction, and do not have any venom. Adults are nocturnal, feeding on the larger animals that emerge at night. Juvenile snakes come out during the day, and feed mainly on small reptiles. As ambush predators, green tree snakes do not actively search for prey, and don’t move very much. They are so lazy they will use the same ambush site for up to two weeks.
This strategy is quite useful for green tree snakes, as it helps them hide from predators. As adults, their green colouration and lack of movement makes them blend in to the leafy trees. Juveniles are also well camouflaged — yellow snakes camouflage well in forest edges, while brick-red juveniles blend in with tree trunks and other non-leafy backgrounds.
We don’t know a whole lot about green tree python reproduction in the wild, as breeding has never been recorded in their natural habitat. What we do know we have learned from captive populations. Females lay 1 to 25 eggs, which she broods and protects for almost two months. The eggs hatch at the start of the wet season, in November. The hatchlings are about 30 cm long, and reach sexual maturity between two and four years of age.
Green tree pythons are popular snakes in captivity, and tend to do quite well once their needs are met. Because of their popularity, their population is under pressure from hunting for the pet trade. There are captive breeding programs however, so if you want to get a green tree python, just make sure you source it from a captive breeder!