They sweep over Canberra each year in the hundreds of thousands, from the cracked, black soil where they were born into the cool dark crevices of the mountains of the Great Dividing Range.
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But bogong moths aren't just a marauding horde invading our houses, hot water systems and halls of power – they are a superfood that tastes a little like "charred pork fat".
Once, their annual migration united families from different Aboriginal nations, who came together to roast the insects on hot rocks in the Brindabellas and the Snowy Mountains, ACT Parks and Conservation's senior Aboriginal ranger and Wiradjuri man Jackson Taylor-Grant said.
"I've had them before, they're a bit nutty in flavour or a bit like charred pork fat. It's really high in fat and protein, so it's really quite a superfood," Mr Taylor-Grant said.
Ngunnawal people have told him how their ancestors would join with the Wiradjuri and the Walgaloo nations to feed off the moth, a ceremony that no longer occurs.
"There are reports from Gudgenby Valley of over 500 fireplaces of different family groups gathering for the bogong moth ceremony," Mr Taylor-Grant said.
"Early European settlers would notice the migration of Aboriginal people up into the mountains to feed on this moth, and upon their return they would come back and their skin would be shining, they would have put on a lot of weight and they looked really healthy and it was generally felt it was from the health benefits of eating the moth, they became very healthy after they had their ceremony.
"It is a shame [it no longer happens] and I guess it's what happens with removing people from their country, they lose traditions that have been going on for what could possibly be thousands of years. It would have been a pretty amazing thing to witness people coming together like that and feeding on this moth."
The migratory moths breed in the black soil of north-western NSW into Queensland before undertaking the 1000-plus kilometre journey to the mountainous regions of the ACT, south-eastern NSW and northern Victoria to hibernate in "sheets" between rocky crevices.
"Basically, the moth doesn't like the heat but the larvae doesn't like the cold, hence why they migrate so the moth will fly from Queensland all the way down," he said.
Problems with larvae absorbing arsenic in the soil also meant humans now only eat the moth "opportunistically", Mr Taylor-Grant said.
Dr Linda Broome, a senior threatened species officer with the NSW Office of Environment and Heritage, said the moths were coming this year much later than usual and in fewer numbers.
"It's the cold weather, I suspect. There's still a lot of snow up at Kosciuszko, it's melting very rapidly but it's been a late spring, so they probably haven't felt the need to [migrate] because the temperatures were low," she said.
"What's happened this year in [the north] is there's been flooding rains ... so a lot of the larvae may have actually drowned because the winter rainfall this year was very much above average in June, July and August. I'm not predicting a huge year this year and it may be something to do with that."
Following the moth's migratory path are predators, seeking to feast on its high-fat, high-protein flesh.
"You can tell when there are bogong moths around because the ravens will start circling the peaks and feeding on the moths," Dr Broome said.
They are also a critical food source for Australia's only hibernating marsupial, the mountain pygmy possum.
"When they wake up, their major food supply is the bogong moths. Because the moths can be up to 70 per cent fat, the possums can fatten on them very quickly and start breeding as soon as the moths arrive," Dr Broome said.
