14/10/2026
We posted about the Bogong moths a couple of weeks ago. Since then, half the east coast seems to have them, and the two questions in our inbox have been the same ones: how long is this going to last, and is it normal?
Here is what the scientists are now saying.
This is the best year in almost a decade
Dr Marissa Parrott, a senior conservation biologist with Zoos Victoria, says the numbers being seen across New South Wales and the ACT are the healthiest the species has had in a very long time, the best year, by her account, in close to ten years.
That matters enormously, because this is a species that nearly vanished. The population collapsed by an estimated 99.5 per cent in the drought years before the Black Summer fires, and the Bogong moth is now listed internationally as endangered.
Two things appear to have combined this spring. Good rain and plenty of food across inland NSW and the ACT produced far more moths than recent years. And warm winds early in the migration pushed them east, closer to the coast and into towns that rarely see them.
So there are more moths than usual, and they are in places they do not normally pass through. Both at once.
Zoos Victoria’s Moth Tracker, where anyone can upload a photo of a sighting, has been inundated.
How long will they be in your house?
Not long.
Dr Parrott’s answer is that the moths will not stay. They are drawn in by bright lights or blown off course by wind, and then they carry on toward the Alps. Dr Caitlyn Forster, an entomologist at the University of Sydney, has put it at days to weeks for any given area.
The confusion comes from the length of the season rather than the length of the stay. The spring migration runs for months, and there is a return migration in autumn. So Australia will be seeing Bogong moths for a while yet. Your laundry will not.
The single most useful thing you can do is switch off outdoor lights you do not need. That is what pulls them off their route in the first place.
What they are actually doing
They are flying to the mountains, and the way they get there is one of the genuinely extraordinary things about Australian wildlife.
Bogong moths travel up to a thousand kilometres from breeding grounds in southern Queensland, inland NSW and Victoria to a handful of specific caves and rock crevices in the Australian Alps, generally above 1,800 metres.
Research published in Nature last year established that they steer by the stars. They are the first invertebrate ever shown to use a stellar compass for long-distance navigation, alongside the earth’s magnetic field.
None of them has made the trip before. The moths that did it last year are dead. Whatever they are using to find a particular cave in the high country, they were born with it.
When they arrive they pack onto the cave walls at densities of around 17,000 moths per square metre and sleep through the summer heat — aestivation, the warm-weather equivalent of hibernation — for three to four months. In February and March they wake, fly home, breed, and die.
Why anyone cares about a brown moth
Because the mountain pygmy-possum eats them.
The possum is critically endangered. It comes out of hibernation under the alpine snow starving, with young to raise, exactly as the moths arrive. When the moths collapsed, so did the possums.
The moths also pollinate native flowers right along the route, and they carry nutrients from the inland into the alpine system. Pull them out and a great deal unravels.
A note of caution
Dr Eleanor Drinkwater, an entomologist at Western Sydney University who works with citizen science groups tracking the moths, has been clear that one strong season is not a recovery. It will take time to get back toward previous numbers, and the species remains endangered.
There is also a tagging study underway — around 14,000 moths marked at Mount Kosciuszko — and researchers want to know where they turn up. Which is another reason to log what you see.
What you can do tonight
Turn off outdoor lights you do not need.
Do not spray them. They are completely harmless.
If one is inside, cup it gently and let it out.
And photograph your sightings and upload them to Zoos Victoria’s Moth Tracker. Researchers are using those records to work out how many are reaching the Alps this year. The moth on your window is data.
They have a long way to go, and almost none of them will make it.
Give the ones that pass through your place a bit of room.
How are they at your place, better or worse than last week? And has anyone logged one on Moth Tracker yet? Tell us below. 🏔️🇦🇺
Sources: SBS News; The Nightly; ABC News; Zoos Victoria Moth Tracker; Nature, stellar navigation in Bogong moths, 2025; 7NEWS.
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