A remote radio tower near Mount Burr in South Australia has attracted millions of ladybugs for reasons no one seems to understand.

The unusual sight was recently reported by wildlife photographer Steve Chapple, who posted several photos and a video of it on his Facebook page.

Contacted by ABC News Australia, Mr Chapple said that he was told by a friend about this place where ladybugs would sometimes converge in the thousands, seven years ago, but their number has since increased manyfold.

This year, there appear to be millions both on the ground and on the radio tower itself.

“I’ve always been astounded by the numbers out there but this year was just phenomenal,” Chapple said. They’re there all day. They swarm during the middle of the day and then they land back in the crevices, the cracks, the pipes during the dark. This is the thickest I’ve ever seen them.”

As for the reason why so many ladybugs are meeting at a radio tower in the middle of nowhere, experts say it’s hard to tell. University of Adelaide professor Andy Austin has two theories:

“Two likely reasons are they are mating aggregations that attract beetles to one spot, essentially to make it easier to find a mate,” he told ABC. “The second possible reason is that it is for protection against predators, particularly birds.”

Professor Austin was interested to know if the little bugs were releasing a detectable scent, in which case the chemical may also act as a deterrent for predators. Steve Chapple said that he didn’t sense any odour from the live ladybugs swarming around, but that there was definitely a foul smell coming from the millions of dead ladybugs covering the ground.

“They’re quite thick underneath and some of the bottom ones are dying,” he said.

Chapple has been telling people about this place for years, and it has become a relatively popular tourist attraction, and with the recent media coverage, it’s expected to become even more so.

“I’ve told so many people about it over the last few years,” the photographer said. “I went up the other day to take a few more photos and there would have been seven or eight cars up there.”

If you’re in South Australia and want to see this unusual ladybug meetup, you should hurry, as Mr. Chapple says that based on previous years, the gathering is about to come to an end.

“You’d have to go I’d say within the next week,” he said. “They’re starting to die in quite dramatic numbers.”