Setting up microphones in national parks and then walking away for a year may seem like a strange kind of science, but it's part of a little-known strategy to track the health of the Australian bush.

Collecting terrabytes of sound data from desert and wilderness, bushland and rivers is just one way scientists are using eco-acoustics to study change in flora and fauna.

The use of sound to investigate natural landscapes is an increasingly important field. Credit:Phil Carrick

Professor Paul Roe from the Queensland University of Techology said using "big data" to track how the sounds of Australia have changed had implications for conservation and environmental projects.

He and about 300 other scientists, artists and musicians recently came together in Brisbane for the fourth international Ecoacoustics Congress, a unique deep-dive into sound and its role in the natural environment.