File Snake

Genus Acrochordus

Reptile

Transcript:

Today on Animal Fact Files we’re discussing file snakes. These snakes are also known as wart snakes and elephant trunk snakes, and all of these common names come from the appearance of their skin! File snakes have loose, flabby skin. In fact, their name in Indonesian means “sack”. Their scales are small and rough, so they feel like sandpaper or a nail file– hence the common name! Honestly, if you saw one of these snakes moving around out of the water, you might think it was dead. The way their body compresses laterally while they slink along a surface looks kind of goopy. Of course, file snakes rarely, if ever, spend time outside of water. These are aquatic snakes!

Technically, there are other snake species known as file snakes, but this video is focusing specifically on the three species of file snakes in the Acrochordus genus. They're found throughout South and Southeast Asia as well as northern Australia. The two larger species predominantly live in freshwater, while the smaller species spends more time in brackish water, however all the file snake species can tolerate saltwater. Heck, they've been observed as far as 6.2 miles (10 km) out to sea! And they don't typically use swimming as their primary form of locomotion.

Although file snakes are competent swimmers, they usually move around by crawling along the bottom of the water column. These reptiles spend most of their time in water no deeper than 66 feet (20 m), keeping hidden in reefs, mudflats, intertidal areas, mangroves, estuaries, lagoons, flooded forests, rivers, lakes, and more. File snakes are nocturnal. During the day they slip into burrows made by other animals, under logs and other debris, or buried amongst the roots of trees. They actually get up close with each other in these environments. In fact, in an approximately two and a half acre (1 hectare) area, there can be hundreds of file snakes!

File snakes live in murky water, so they hunt using senses other than sight. Their knobby scales have microscopic, hair-like structures that help them feel the environment around them. They can sense the movement of fish in this way! These snakes coil around their quarry to hold it in place, having rough skin helps with this! They don't constrict like some of their closest relatives, the colubrids, do. File snakes also lack venom. They're considered harmless, at least to humans, gobies, eels, and catfish might disagree. File snakes also eat crustaceans and snails, although their primary diet is fish.

Living nocturnally and aquatically helps file snakes avoid predators. They're essentially helpless on land, so they're an easy target if caught in this precarious predicament. Predatory birds, crocodiles, otters, and large fish all eat file snakes if given the opportunity. Humans also hunt them and use their skin to decorate jewelry. It's unknown how this impacts their population, but considering they are slow growing animals, it may be difficult for them to recover from large losses.

Very little is known about file snakes in their early years. It takes at least three years for them to reach reproductive maturity, and that's specifically for the smaller species. They don't reproduce annually, so it takes at least a year, sometimes as many as ten years, before they have another batch of babies, and they only have about a dozen babies on average depending on the species. They gestate for half a year or even slightly longer and give birth to live young. Where those babies go and what they do as juveniles is still largely a mystery!

The smallest file snake species maxes out at about 3 feet (91 cm) long while the largest species can more than double this, reaching upwards of six and a half feet (2 m) long. The largest of these are the females who can weigh up to 22 pounds (10 kg) at their largest. The females are likely larger than the males because they have to sustain the eggs that develop inside them. In fact, female file snakes have been observed specifically seeking out larger meals than males, and it's likely for this reason!

Like crocodiles, file snakes eyes and nostrils are found on the top part of their head, so they can stick their nose out of the water to breathe with nothing else showing. They're typically grey to brown with lighter stripes along their sides, helping them blend in with their turbid surroundings. They can remain submerged for hours without needing to take a new breath, thus keeping them away from the watchful eyes of predators. File snakes also have a different method for shedding their skin. Instead of peeling out of their skin and turning it inside out as they shed, the skin loosens and the file snake simply crawls out!

For more facts on file snakes, check out the links below. Give a thumbs up if you learned something new today. Thank you to our Patrons SpikeSpiegel93, Dad, and everyone else for their support of this channel! And thank you for watching Animal Fact Files!