It is quite possible that if you are out wandering along the creeks and slopes of South and West Australia, you might be startled by a loud, gurgling sound beneath your feet. Don't be afraid. It is only the sound of the Australian giant earthworm. This large creature is entirely harmless, even though it might not sound like that.
The sound of a giant earthworm squelching its way in the darkness along its wet burrow could frighten even the bravest. Australia has over 1000 species of native earthworms, but the region of Gippsland is home to the largest and undoubtedly the most famous of all earthworms. That is the Australian giant earthworm.
During the late 1870s, when railway workers were surveying the Moe to Bunyip section of the rail line around Brandy Creek, this strange creature was first discovered. As they had never before seen an earthworm of this size, they mistook it for a snake. Ever since then, it was handled with trepidation.
When it arrived at the University of Melbourne, Professor McCoy examined it and put their fears to rest. This was deemed a giant species of earthworm, and it was entirely innocuous.
This gigantic earthworm was featured in festivals and TV shows, and it starred in Sir David Attenborough in the BBC's 2005 series. However, despite all the attention, a lot of its habits and behaviors remain a secret. These earthworms are hidden beneath the clay pastures of Gippsland.
Australian Giant Earthworm Characteristics
The giant earthworm is challenging to study because of its life under the ground. They are difficult to track and follow. This is why scientists have not been able to replicate their natural environment in captivity, and the answers to many questions such as life span remain a mystery.
Giant earthworms have been observed to live for over ten years but only in a protected environment.
Since they live deep in the soil and because colonies usually have many more adults than young, these worms likely live much longer.
These elusive giants have been known to science only since the late 1800s. As they were mistaken for a snake, they were treated with great care and fear. It was soon discovered that they don't have scales and teeth and that they are indeed only giant worms.
Despite its size, this is a highly vulnerable species. The giant earthworm was isolated to just 150 square miles at the southeast tip of Australia. Its habitat was once in the dense forests. Sadly, it has been almost entirely converted to farmland. In these spaces tilling and toxins have pushed the giant earthworm to the brink of extinction.
The most significant characteristic of these worms is that they can be heard working underfoot in these regions. They only surface during heavy rains to avoid drowning in soggy soil. Their burrows have very wet walls. Due to this, when the giant earthworm moves quickly within its caves, it makes a gurgling sound that is quite loud and can be heard above ground.
Since this sound is quite loud, it has been known to terrify those not warned of it.
Giant Earthworm Size – How Big Is It Actually?
The burrows of the giant earthworm are up to 5 feet deep. They use their muscular heads to chew through the substrate while ingesting fungi, bacteria, algae, and other microbes.
Since these worms don't have teeth, they process the small rocks in a gizzard, where they are used to grind down food. The wastes the giant earthworm expels at the other end are called castings. The worms block their burrows with them sometimes. They go back to the same spot and cast in areas where they have already left other cast material, which signifies that they have separate burrows for waste.
These worms are hermaphrodites. Adult individuals have both male and female sex organs. The giant earthworm can store sperm year-round and can potentially mate whenever it meets another earthworm. After this encounter, they store the sperm, ready for producing eggs whenever conditions are favorable. Since their population density is sparse, this is an advantage.
When the egg is then laid in a chamber in the burrow, it can take as many as 12 months to hatch. When hatched, the foot-long the baby is already huge. These earthworms grow slowly over the rest of their life. They can grow up to 6 feet long and grow through their entire lives, as long as 15 years.
Where Can It Be Encountered?
Australia's long isolation has given rise to an incredibly unique diversity of life that. Many critters in Australia can kill you, but the giant earthworm is just a gentle giant. It is a delicate colossus that is currently endangered. The giant earthworm can grow up to 6 feet and double in its length when threatened.
They are found in the stretches of Gippsland in South and West Australia. Since they have a limited ability to move from one place to another and a fragile body, they can be threatened by the expanding farmlands. Currently, there is a campaign to educate local farmers about their impacts on these incredible creatures.
The giant earthworm cannot recover quickly from changes to their environment or move to a better place. If the soil dries out, or if there's flooding or toxins are added to the soil, the giant earthworm population diminishes.
It is still unknown how they mate in burrows barely wide enough for one. It could be that they are emerging to breed on the surface, which could also leave them vulnerable. Australian giant earthworm is very sluggish on the surface, and it would be very vulnerable to desiccation and predators if they stayed above ground for too long.
The Plea Of The Giant Earthworm
Since the giant earthworm colonies are small and isolated, and their reproductive rates are slow, they don't reproduce fast enough to replenish their numbers. Combined with their slow maturation, their small populations are vulnerable.
The natural habitats of the earthworms are grasslands. They can survive beneath pastures, but cultivation, heavy cattle grazing, and effluent run-off will affect this species. They require moist loamy soil to thrive, and so dense tree planting negatively affects soil humidity, which in turn negatively affects the species' habitat.
Sadly, they were still not found to be able to reproduce in captivity. South Gippsland and Baw Baw councils have introduced a planning scheme that overlays safeguards considering the giant earthworm habitats. Since it is likely that these worms existed in towns in the past but have moved due to development, their narrow habitats must be protected.
Currently, some laws prohibit building in the vicinity of the slopes where the giant earthworm population can be found. There are prospects for conservation of the earthworm that are discussed within the known framework of species biology.