Yellow Clubtail thrives in urban Garonne waters

July 14, 2026Western European broadleaf forests

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dragonflies (Gomphus flavipes) are appearing on the Garonne in midsummer — a sign that the river's bed still supports the clean gravel habitat their larvae demand. This threatened species needs years to develop underwater, buried in unsilted sediment where water clarity and flow remain high. Its presence here, in an urban reach, speaks to ecological recovery.

Over the past two months, the river has hosted more than twenty odonate species, a remarkable diversity for a city waterway. Each represents a different tolerance for current, depth, and substrate condition. Together, they map the Garonne's remaining capacity to sustain aquatic life — and suggest that despite urban pressures, the river's fundamental ecological functions are still intact.

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