Linnea Emneby

Stories

Bogong moth swarms return to southeast Australia after 99.5% population collapse

Tracking the migration and theorizing on the population surge

For decades, spring in southeast Australia meant billions of bogong moths streaming toward the Alps to escape summer heat. Then, between 2017 and 2019, severe drought in their breeding grounds collapsed the population by up to 99.5 percent — and in 2021 the moth was listed as endangered by the International Union for Conservation of Nature (IUCN).

Updated Oct 19