The Weird World of the Nanboo Forest (and the bird-eating snail)

The Weird and Wild World of the Nanboo Forest

The nanboo forest is a unique biome found only in the wettest equatorial regions of Serina in the Pangeacene. In this environment, myrmecophyte trees are limited to small understory forms with relatively non-aggressive ant species and the majority of the forest is composed of the tall pseudostems of the nanboo plants, which are an unappealing home for ants and not adapted to support them as symbiotes as are trees in many other parts of the world. Here, where rain is almost a daily occurrence, these enormous banana-like grasses thrive and reach immense sizes, smothering almost all competitors.

Nanboo forests are thus notable for having a low diversity of plant species but a very high one of animals. The nanboo's leaves and stems are edible and, though not especially nutritious and made mostly of water, are so abundant and easily digested that many insects and animals are able to survive in the forests by browsing on the plants and consuming their fruit and nectar. Plant-eating insects are highly abundant and provide food for songbirds and insectivorous tribbets, especially tribbats and handfishes. The nanboo does little to protect its leaves from herbivores, instead relying on its rapid growth rate and ability to regenerate any portions of itself which are damaged, and so the result is an ecosystem very different from the sunflower forests that thrive in other regions. Small circuagodonts do occur here, where they have specialized their teeth as saws to feed on the young, fleshy pseudostems by turning their head sideways and cutting them down with their beaks, then slicing the felled stem into small circular portions for swallowing as someone might slice a banana to add to their breakfast cereal. Other molodonts are largely absent, for this is an environment with very few nuts or large seeds worth eating. The seeds which the nanboo produce are tiny and hidden in fleshy fruits that instead appeal to birds and tribbats, who then distribute them in their droppings.

The wet climate and high abundance of small prey in conjunction with no aggressive predatory ants in the nanboo forest has allowed the evolution of a very unusual group of predators in the high canopy of the nanboo jungle - carnivorous, nocturnal land snails known as the slime anglers, most of which hang high up in the leafy crowns of the nanboo stems. The slime anglers are effectively slugs, with only a small internal remnant of their shells, and range from three to a whopping twenty inches in length. They include among their ranks the largest land gastropods since the land snails of the Hypostecene, some of which can weigh more than three pounds. All of them spend the days tucked away underneath the arching leaves of the nanboo plants and emerge to hunt after dark, when they drop their fishing lines down from the canopy - long dangling strings of mucous produced from a series of glands on their undersides, infused with a sweet-scented pheromone mimicking a nectar-filled flower, which serve to capture night-flying insects as well as small vertebrates. Ants and beetles are attracted to the hidden lines by the scent of a sugary meal and become entangled flying through the dense vegetation, which in turn may attract small birds and tribbats which themselves can also become entangled. Throughout the course of a night the lines become covered in the struggling bodies of dead and dying animals, and roughly an hour before sunrise the hunter finally begins pulling the line back in. It recycles the fishing line every morning by eating it along with all that has become attached before retreating back to shelter for the day, flattening its body and moving over hundreds of small sticky suction cups on the underside of its foot that serve to adhere it to the underside of the leaves.

The largest slime angler is a fat, swollen creature known as the bird-eating snail, and its name is not inaccurate. Its method of feeding is slightly different from its competitors, and it is not entirely nocturnal. Rather, it wakes up several hours before dusk and climbs to the upper surface of the nanboo's leaves and to the branching flower stalks at the tops of the plants. It then proceeds to lay down a thick, tacky layer of sticky mucous along the blossom stem and the tops of the leaves below it, which hardens within an hour to a consistency like tar. The snail then returns to its hiding place at dusk, and waits for roosting birds to land on its trap. As diurnal birds search out a secure perch to spend the night, some inevitably alight upon the leaves booby-trapped by the snail and become ensnared. The more they struggle, the more the slime entraps their feathers. As soon as night falls, the snail then glides silently out from its lair, over the hapless birds, and swallows them alive in an enormous, cavernous mouth that it distends from its underside. Additional prey in the form of night-feeding tribbats may continue to get stuck throughout the course of the night, and the snail has only to wait for its food to come right to its table. In one night, the snail can eat as much as a quarter of its body weight in prey, and becomes highly distended. After such a large meal, it will retire for as long as ten days to digest it before setting its trap again. Gorging on anything and everything which gets stuck in its snares, it is no wonder that the bird-eater is able to grow as large as it does.

Between feedings, the bird-eating snail hides underneath large leaves or in the crowns of the trees, where it is protected from dehydration. It is at this time that it enters a torpor-like state and is vulnerable to its own predators, namely larger birds which can hook it out with their beaks and tear it apart. At times they may even become so engorged they cannot hold themselves up and fall to the ground, where in their defenseless state they are readily eaten by scavengers.

above: the bird-eating snail. Illustration by Trollmans.Deviantart.com