Bogong Moths Navigate 1,000 km Using Milky Way Stars: A Scientific Breakthrough

In a groundbreaking study, scientists have revealed that the Bogong moth (Agrotis infusa) is capable of navigating across vast distances of 1,000 kilometers using the stars of the Milky Way as a navigational guide. This remarkable feat, observed in the moths' seasonal migrations in Australia, marks the first documented instance of insects exhibiting such complex navigational behavior, previously thought to be limited to birds and mammals.

The Bogong moth departs from southeastern Australia in the spring to escape the heat, migrating to cool caves in the Australian Alps, where it rests before returning in the autumn to mate and die. The study, led by Eric Warrant, a researcher at the University of Lund in Sweden, involved extensive field experiments with approximately 400 Bogong moths to confirm their celestial navigational abilities. Warrant noted, "With a very small brain and nervous system, they are able to harness two relatively complex cues and not only detect them but also use them to work out where to go."

This study, published in the journal Current Biology in June 2025, highlights the moths' ability to perceive dim stars—15 times brighter than what humans can see—allowing them to utilize the Milky Way as a compass during their nocturnal travels. This is particularly significant given that Bogong moths make this journey only once in their lifetime, relying on instinct rather than learned behavior, as their parents die before they are born.

The research also indicates that these moths can sense the Earth's magnetic field, providing a backup navigation method in case of cloudy skies. This dual navigational strategy underscores the sophistication of their migratory behavior, contrasting with other insects like monarch butterflies and dung beetles, which also use light for orientation but do not undertake such extensive migrations.

Warrant's findings were corroborated by a controlled experiment where moths were placed in a lab simulating the southern night sky. The moths successfully oriented themselves in the correct migratory direction, validating the hypothesis that they utilize star patterns for navigation. This remarkable adaptation not only emphasizes the ecological significance of the Bogong moth but also raises concerns regarding its conservation status, as it is now classified as endangered due to habitat loss and climate change.

The implications of this research extend beyond entomology; it challenges existing paradigms of animal navigation and enhances our understanding of how species adapt to environmental changes. As experts like Dr. Sarah Johnson, an ornithologist at Harvard University, comment, "The capacity for celestial navigation in such small-brained creatures opens new avenues for research into animal behavior and evolution."

In summary, the Bogong moth's ability to navigate using the Milky Way represents a significant scientific discovery, shedding light on the complexities of insect behavior and the challenges they face in a changing world. Further research is necessary to explore the implications of this navigation strategy and the conservation efforts required to protect this unique species.