Orange‑coloured sea water has been spotted around parts of the island’s coastline, with officials confirming it is caused by a seasonal bloom of Noctiluca scintillans.
The naturally occurring plankton appears in Manx waters periodically during the summer and has been recorded in previous years, including 2018, 2019, 2021 and 2024.
It is not considered harmful to humans, but the Department of Environment, Food and Agriculture is advising people to avoid swimming where the water looks discoloured.
Dense blooms can cause minor skin irritation or respiratory discomfort for some individuals, and may also attract other marine life such as jellyfish.
The department says the phenomenon is temporary and will fade as conditions change.
