Koalas of St Bees Island. Image Credit: Andrew Gregory/Australian Geographic

Unravelling the mystery of koalas on St Bees Island

  • August 26, 2015

These introduced species are behaving in mysterious ways on the small tropical island of St Bees, off the coast of Mackay, Queensland

Koalas were relocated from Proserpine, 125km north of Mackay, to St Bees in the 1930s, when the island was leased and grazed. Despite being free from predation and diseases 
ravaging mainland populations, they've maintained a relatively stable colony size.

To scientists, this stability is an ongoing conundrum that's continuing to be investigated. Other island populations tend to thrive to the point that they multiply exponentially, ultimately perishing after eating themselves out of house and home; or they fail to thrive, and quietly disappear.

Read the full story in #128 of Australian Geographic.