One of Mandurah's oldest dolphins passed away on the weekend.
Zero One, who was thought to be in his late 30s, survived several strandings and at least one shark attack.
Estuary Guardians Mandurah reported the death on their Facebook page.
"Yesterday elderly dolphin Zero One was found deceased in the lower reaches of the South Dandalup river, near where it meets the upper Murray River," the post read.
"01 was the senior member of (what seems to be) the highest ranking male alliance the King's Crew and still chasing the girls in his last weeks.
"It is likely 01 has fathered many of our present dolphins."

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