Picture this: you open the front door and a cloud of tiny moths fly in like they've booked the spare room. For most New South Wales residents lately, that's been real life. Swarms of Bogong moths have been turning up in homes and even boots, and researchers say it could be a sign of recovery! 

So, Where Have These Moths Been?

Each year Bogong moths migrate to the NSW Alps to escape the summer heat. They set off from inland breeding grounds across south-eastern Australia, with some travelling up to 1,000 kilometres to reach the cool caves. In a good year, more than four billion make the trip. Then numbers crashed by as much as 99.5 per cent in 2017, and the species is now listed as endangered.

So when about 800 sightings were logged on iNaturalist within days, scientists took notice. Zoos Victoria's Dr Marissa Parrott says her Moth Tracker project received more Bogong sightings in a single month this year than in its best year, 2024.

As Dr Parrott puts it, "There have been happy tears in my office because this is what nature should be."

What's Behind the Comeback?

Researchers aren't certain yet. Linnea Emneby from Invertebrates Australia suggests more rain in northern NSW may have given larvae plenty to eat, and scientists believe a run of wetter weather helped, though they're still studying the causes.

Earlier this year, researchers from Western Sydney University and Invertebrates Australia tagged about 14,700 moths with blue dots at Mount Kosciuszko, with volunteers running "bug lanterns" at 50 sites nearby. None have been recaptured, which was expected given how small a slice of the population was marked. Led by Associate Professor Kate Umbers, the Bogong Watch project is working to map where these travellers actually go.

Why Do Tiny Moths Matter So Much?

Because they feed the mountains. The moths are a vital food source for the critically endangered mountain pygmy possum, which relies on them after hibernating for up to seven months. They also pollinate native plants along a journey of up to 1,000 kilometres, and researchers have shown they navigate using the Milky Way. (A creature lighter than a Tic Tac reading the night sky. I'm in awe.)

It's not all smooth flying, of course. Dr Eleanor Drinkwater is clear that the moths are still endangered, and a severe El Niño is forecast to bring soaring temperatures this summer, so scientists are hoping the rebound lasts.

What Can We Do When One Lands on the Couch?

The advice is lovely and simple. Dr Drinkwater suggests catching and releasing any moths indoors, or turning outdoor lights on and indoor lights off to draw them out. Dr Parrott adds that we can switch off outdoor lights, keep cats indoors, avoid insecticides and plant native flowers for food along the way. And if you spot one, log it on iNaturalist or Moth Tracker so researchers can follow the migration.

You don't need a perfect garden or a moth-proof home. One switched-off light is still a step forward! This story is a little reminder that Moth-er Nature (sorry, we couldn't help ourselves) can bounce back when we give her a chance.

If this story has you dreaming of a garden that welcomes a few winged visitors, you might enjoy browsing our plant kits, cards and seeds for gentle little ways to get growing. A small pot of something green is an easy place to start.

Ready for another feel-good story? Check out our blog here about smart road signs helping to protect wildlife!

With love,
Ellie xo

Frequently Asked Questions

What are Bogong moths?

Bogong moths are peanut-sized moths, about 2.5 to 3.5 centimetres long, that migrate each year to the NSW Alps to escape summer heat and return to inland breeding grounds in autumn.

Why are there so many Bogong moths in NSW right now?

Researchers aren't sure, but they suggest increased rainfall, a warmer winter and favourable winds may have played a part. Scientists are still studying the causes of the rebound.

Are Bogong moths endangered?

Yes, the Bogong moth is listed as endangered on the IUCN Red List. According to the University of Sydney's Dieter Hochuli, it is not listed as endangered in NSW or federally.

What should I do if Bogong moths get inside my house?

Gently catch and release them, or turn your outdoor lights on and indoor lights off to draw them out. Experts also recommend avoiding insecticides and other toxic chemicals.

How can I help track Bogong moths?

You can photograph and log sightings on iNaturalist or the Moth Tracker website. Volunteers have also helped researchers with the Bogong Watch project by running "bug lanterns" to look out for tagged moths.