Swarms of animals can wreak havoc. Just think of piranhas swarming their prey or locusts descending on farmland. But sometimes swarming behaviour can be benign, even beneficial.  

This week, we’ll hear about hordes of animals from both ends of the spectrum. From pests running amok to endangered species swarming to fuel biodiversity.  

Reporting by Die Hu, Harry Sekulich, and Bec Pridham.

These stories were produced for the Science Gallery and were developed with mentors from All The Best.

The Yarn is produced at the Centre for Advancing Journalism at the University of Melbourne.