Australian little penguins face heightened risk from marine noise

Researchers at Curtin University in Western Australia used high‑resolution micro‑CT imaging to create 3D digital models of the heads of three naturally deceased little penguins (Eudyptula minor). The study produced the first predicted audiograms for the species both in air and underwater, showing that the birds can hear sounds from about 200 Hz to 6,000 Hz underwater. This range overlaps with typical ship noise, which spans roughly 20 Hz to 10,000 Hz, as well as noise from coastal construction and recreational activities.

Lead researcher Chong Wei explained that the little penguin’s habitat often coincides with busy navigation routes and coastal development, making the species “particularly vulnerable” to increasing ocean sound pollution. Co‑author Christine Erbe added that continuous exposure to elevated noise levels can raise stress and interfere with feeding behavior. The findings are intended to inform marine‑noise management plans aimed at reducing harmful acoustic impacts on the declining penguin populations. The research was published in the journal Royal Society Open Science.