A large, unique native slug spotted on pool decks and trees throughout Brisbane is intriguing home owners with its brightly-coloured shape on its back.
The striking red triangle slugs have emerged due to wetter than normal weather conditions in the south-east corner.
Queensland Museum honorary research fellow Dr John Stanisic, aka "the snail whisperer", said finding native slugs in the backyard was a very good sign of a healthy ecosystem.
"Everyone should have a slug in their backyard," he said.
He said the recent rain encouraged the slugs to venture out of their "hidey holes" in search of food.
"They're nocturnal and they love wet conditions because when a slug is active they're continually secreting mucus to keep themselves moist, and the rain helps it retain moisture," Dr Stanisic said.
"They can make their way up trees to heights of 12 metres feeding on micro algae found on the bark.
"Before dawn they'll make their way back down into their hidey-hole again."
A slippery slug of many colours and talents
The red triangle slug is Australia's largest native land slug and is seen in areas from Illawarra to the Daintree in far-north Queensland.
Dr Stanisic said the most spectacular-coloured red triangle slugs exhibited bright red, gold, or even orange colours, and were often spotted in higher terrain.
"The triangle is always on their backs except on the bright orange variety found at Mount Bellenden Ker in far-north Queensland, where you can see them on the trees from the cable car if it's raining as they're so bright," he said.
Researchers believe the distinctive triangles offered clues to the slug's evolution.
"A slug is a snail without a shell, and from the same group of animals, so what makes these slugs different is they hold little calcium granules in the red triangle which shows how they evolved from a shelled snail," Dr Stanisic said.
"The pneumostome is also there in the triangle and is the breathing pore of the slug.
"What makes the red triangle slug so unusual is that it doesn't have a lung. It has a whole system of tubules.
Finding slugs high and low
Home owner Dot Williams said she had found slugs in pot plants on the deck and under bricks in her backyard in Brookfield, west of Brisbane.
"I've seen them over the last couple of months and they're as long as my middle finger," she said.
"They're really fascinating, and I think they're cute as well as making long trails [around my yard].
Dr Stanisic said he hoped more native slugs will be seen and he was doing all he could to keep the population strong.
"They're part of the snail story here in Australia as we have 2,500 native species of snails and about six to nine species of native slugs, so it's important to have them," he said.
"We have the slugs in my backyard and recently one fell into our saltwater swimming pool. I dove in and saved it and popped it back on the pool deck.
"They clean the pool deck for me."
