Warning as fast-spreading invasive pest swarms Aussie suburbs: 'Hundreds of them'

Yahoo

14-02-2025

A rapidly-spreading invasive pest that was first discovered in Australia less than two years ago is causing massive destruction in thousands of suburban backyards. Over the past few weeks, numerous Brisbane residents have reported finding huge outbreaks of exotic papaya mealybugs sucking the life out of frangipanis and fruit trees in their gardens.
The infestation has become so bad as of late, it's almost impossible to miss the mounds of insects as soon as you head out the door, with local horticulturists claiming they've been inundated with emails from concerned and puzzled homeowners.
'I can walk up and see them out the window now,' Tim Low, one of the original founders of the Invasive Species Council, told Yahoo News Australia on Friday. 'I've just checked a frangipani that's one minute walk from here, they're all over that. And I talked to a friend, yep she's got them.
'I've been wiping hundreds of them off my green pawpaw — they're really greasy — it's not very nice work. It's kind of slimy, and you've got to do it every, like three days, and they just come back really fast.'
The author of Feral Future: The Untold Story of Australia's Exotic Invaders said he first noticed the creatures on his pawpaw last year, but assumed 'they were just some standard pest that's been in Australia for decades'. Roughly two weeks ago he officially identified them as papaya mealybugs, a Central American insect that was first detected in the country in July 2023 when it made an appearance in Darwin.
They quickly spread throughout the city, Palmerston and Howard Springs, prompting the Northern Territory Government to release a species of native ladybirds nicknamed the mealybug destroyer.
However, by 2024 the pest had travelled to South East Queensland and Townsville, placing the state's papaya industry at risk.
'It has to have been a plane moving between Darwin and Brisbane, or a truck or a car that's brought them, because the small bugs are pretty well invisible at only two to three millimetres-long,' Tim said, noting female mealybugs don't have wings.
'It's really interesting because they not only have to get to Brisbane, but they've got to get to a pawpaw, a frangipani, hibiscus or one of the other food plants they use.'
Papaya mealybugs have over 200 host plants, including avocado, mango, pomegranate, grapefruit, cherry, eggplant and sweet potato.
Tim, who is writing a second book on invasive species, told Yahoo the recent outbreak is a good example of the fascinating — and terrifying — ways 'insects are getting around these days'.
'It's really noticeable to me that the flow of species into Australia has speeded up,' he said. The number of pests that are on the move appears to be 'unprecedented'.
'Every year there's a range of new pests turning up. This is indicative of a very, very volatile situation. It's never going to end,' he added, pointing to the tomato brown rugose fruit virus that was detected in South Australia in September.
The noticeable increase is largely in part due to 'the high levels of people and products travelling around the world' today, with bugs and seeds likely entering via people's clothes, luggage and overseas shipments or packages.
As for the papaya mealybug, there are concerns it will continue to spread to other parts of Queensland, with the government urging those who do find them outside of Townsville and the state's southeast to alert biosecurity authorities.
It is not known if the insect will head further south into NSW, but it's not uncommon for pests to appear in areas that differ from their native climate. 'In terms of predicting how far south they'll go, I mean, Sydney possibly, maybe not, but certainly north of Brisbane,' Tim said.
🌳 Thousands of critters 'swarm' backyards and gardens
🐜 Aussies warned about invasive creatures 'on the move'
🐸 Major problem in bold plan to eradicate $1.5 billion invasive threat
Papaya mealybugs can cause severe damage by sucking sap out of green fruit or tree stems, and then excreting it back onto the plant, causing a 'sooty mould' to grow and giving it a 'black appearance'.
If it is still early in the infestation, Aussies can wipe off the pests and the waxy coating they produce and dispose of them in a sealed bag in the general waste, according to the Queensland Government.
Ladybirds can also be sourced from suppliers and introduced into the backyard. If you do prefer to use a pesticide, 'make sure it's very oily or very soapy — something that really soaks in', Tim added.
Each female mealybug can lay up to 600 eggs in a short period of time, which is why they can sometimes 'appear' almost out of nowhere, well-known Brisbane horticulturist Jerry Coleby-Williams said on his Facebook page last week.
'In my experience in my garden, the spread of this pest is so rapid that biocontrols alone are insufficient,' he wrote.
'Quick control can be achieved by spraying with organic certified products including neem oil, horticultural spraying oil (including white oil) or horticultural soap,' Jerry Coleby-Williams continued, urging gardeners to only do this when temperatures are under 30C so the foliage doesn't burn.
'And don't hack off affected branches, you'll rob the plant of energy when it needs it most.'
Do you have a story tip? Email: [e-mail].
You can also follow us on Facebook, Instagram, TikTok, Twitter and YouTube.