As You can see the Pandanus Tree roots offer a large amount of Security to the Arafura Filesnakes.

By hiding inside of these roots the Arafura has Darkness, Contact Security from many sides, and can breath without fear of predators from above or below.

Filesnakes are eaten by large fish such as Scleropages and Fork-tailed Catfish (Ariidae); both freshwater (Crocodylus johnstoni) and saltwater (C. porosus) crocodiles Whistling Kites (Haliastur luecogaster), Black-necked Storks (Xenorynchus asiaticus) and, probably most significantly: White Breasted Sea Eagles (Haliaetus leucogaster).

The sea eagles seize the snakes when they surface to breath. Large Fish and Crocodiles will seize the snake while it is swimming and moving around.

Those are some of the reasons why Arafuras' are nocturnal and spend much of the day hiding in dark tight places.

As you can see there is a lot of vegetation overhanging the water. These snakes require a lot of Security and Contact Security.