How big is the problem of invasive species? In the words of Deakin University’s Professor Euan Ritchie, ‘the short answer is: it’s massive’. Invasive genes and species are one of the biggest environmental problems facing Australia and the number one cause of native species extinctions. They also cause immense economic and cultural damage; since the 1960s, Australia has variously spent and incurred losses amounting to $390 billion due to invasive species.