Gisborne District Council has identified an unwelcome intruder in local waters — the Asian date mussel.
This small brown mussel, known for its invasive nature, was discovered during routine sediment sampling along the estuarine environment between the Taraheru and Waimata rivers.
The mussel poses a significant threat to the region, the council said in a statement.
It forms dense mats, alters sediment composition and out-competes native species for resources.
Despite being a marine species, the mussel can thrive in estuarine environments with tidal seawater flow.
There are no suitable methods for eradicating or containing this pest.
To prevent further spread, boat owners must thoroughly clean their vessels before entering new waterways. This includes trailer boats, jet skis, waka and kayaks.
Council biosecurity team leader Phillip Karaitiana emphasised the urgency of following the “check, clean, dry” protocols for recreational watercraft moving between regions.
“We cannot afford to let new species into our district waterways,” he said. “Vigilance and preventive measures are crucial.
“We believe this mussel was brought into our waters through a contaminated vessel.”
