Robe Valley, Western Australia
In the arid Pilbara outback of north-western Western Australia lies the Robe Valley — an ancient, weathered landscape of hummock grasslands and open woodlands.
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Torrential cyclonic downpours deliver heavy rainfall to this parched environment, turning dry riverbeds into seasonally flowing waterways. While surface waters are fleeting, beneath the ground, freshwater flows year-round through hidden alluvial aquifers, sustaining sun-scorched vegetation from below.
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Robe Valley's terrestrial ecosystem is groundwater dependent.
Diverse groundwater fauna
These permanent subterranean rivers provide more than just water for surface life. The aquifers themselves are home to an exceptional diversity of groundwater fauna (stygofauna) with 48 species recorded in just a 17-kilometre stretch. Among them is the threatened the blind cave eel (Ophisternon candidum).
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Many of these creatures are living fossils, evolutionary relicts whose ancestors once swam through rivers or crawled across the forest floor back when this part of Australia was covered in wet temperate forest millions of years ago. Now, their specialised adaptations and dependence on permanent water confine them to the dark, stable environment underground.​
Beneath dry creek beds water flows year-round.
Balancing environmental and economic interests
Not only rich in groundwater biodiversity — the Robe Valley is also rich in iron ore, the primary driver of Western Australia’s economy. Industrial use of groundwater, including intentional aquifer drawdown to access minerals, can place severe pressure on these fragile and little-understood subterranean communities.
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Western Australia has strong legislation for the protection of subterranean fauna, but for these laws to be impactful they require better understanding of the communities under threat. Improved knowledge of species’ ecology through innovative monitoring tools are needed to ensure these high-conservation-value ecosystems persist, while balancing their protection with the region’s economic interests.