A dog walker in Western Australia's Wheatbelt was startled after she discovered what appeared to be 'human-shaped effigies' hanging from a tree.
But experts have revealed the structures were the result of venomous caterpillars.
Jerry May shared photos of the clusters of branches hanging from trees with Yahoo News, describing how 'one definitely looked person-shaped'.
She compared the structures to mandrakes in the popular Harry Potter novels, magical plants resembling a crying, human-like baby.
Another of the bizarre finds looked like a hanged body.
But University of Queensland venom expert Dr Andrew Walker confirmed the creepy structures were created by venomous processionary caterpillars.
They form lines along the ground and spin large nests, such as those seen by Jerry May, which can include between five and fifty of the creatures.
'If you do open one up, it usually contains a lot of silk, a lot of caterpillars, a lot of shed skin, and a huge amount of poo,' he said.
A woman walking her dogs in the Western Australian Wheatbelt was alarmed by what appeared to be 'effigies' hanging from trees (pictured)
Experts revealed they were nests created by processionary caterpillars (stock image)
'In some cases, you'll see a tree that has lost all its leaves and wonder where they've gone, and then you'll find a processionary caterpillar.
'Sometimes, as soon as you open them up, there are clouds of their tiny hairs in the air - and some people are going to react very badly to them.'
The caterpillars, also known as itchy grubs, are often spotted in armies marching head-to-tail along the undergrowth.
They have featured in an episode of the animated children's show Bluey, with the title character and Bingo admiring them.
However, the creatures can be a risk for people and animals, with the Australian Geographic urging people not to touch them.
Their tiny hairs can become dust and cause severe skin irritation.
Dr Walker warned the tiny hairs could work their way into the skin and release toxins into the tissue and intestines.
The caterpillars are the larvae of an insect called the bag-shelter moth, which is also hairy and can cause a strong allergic response.
The grubs, which march in lines head-to-tail, have featured on the children's show Bluey
While still larvae, clusters can be found at the base of food trees in coastal areas.
For inland locations, like the Wheatbelt, they are typically found in the branches.