The giant dragonfly (Petalura gigantea) is an elusive and endangered species, that relies on upland swamps for survival. Detection of the species is highly dependent on species knowledge and survey effort, which constrains the use of giant dragonfly as an ‘umbrella species’ that is, a species whose protection also helps protect many other plants and animals that share its habitat. To address this challenge, the Surface Water Science team, as part of the Environmental Outcomes Monitoring and Research Program (EOMRP), has developed a novel environmental DNA (eDNA) assay to detect traces of the species in swamp water. This improves our chances of detecting the species and expands the timeframe in which monitoring can take place.

Researchers combined eDNA sampling with water balance modelling. By linking these approaches, researchers can better understand the conditions that sustain giant dragonfly and improve conservation efforts. The findings show that swamp water can carry DNA from the dragonfly’s burrows, making it possible to detect their presence even when individuals are not seen.

The new method should enable improved management of upland swamps, which are under increasing threats from climate change and land use pressures. The study also highlights the potential for using eDNA to detect other rare swamp-dwelling species. The method has already been used to confirm two populations of giant dragonfly that were previously speculated, but unconfirmed. The method should aid detection of the species and could prove useful for impact assessment and distribution monitoring. This research, alongside studies on the Environmental Water Requirements of upland swamps, will support informed water management decisions and enhance conservation strategies for these fragile ecosystems.