Environment officers are investigating mystery substances washed up along the Anglesey coast.
The appearance of fatty substances on beaches across the island has led to a council warning for residents and visitors to avoid the greasy residues.
Recently, white substances have been found along the west coast at Porth Nobla, Tyn Towyn, Cymyran, Aberffraw and Rhosneigr. On Wednesday, a ball of yellow fatty substance was discovered on Cemaes beach on the north of the island.
Natural Resources Wales say they believe the substances could be palm oil, paraffin oil or vegetable oil, all of which are dangerous to dogs if ingested.
Sian Williams, the head of North West Wales operations at NRW said: ”We have fantastic beaches in Wales so it’s important we look after them for people to enjoy…we are working with Isle of Anglesey County Council to tackle this, as well as the white palm oil which has affected beaches in the area, and would advise people to listen to advice and keep their dogs on a lead. Our local reserve manager in Newborough is also working to clear the white palm oil and put up warning signs around the beach at Llanddwyn.”
Anglesey Council’s maritime officer, Iwan Huws, said the beaches remained open but advised the public to avoid contact with the substances, supervise children carefully and keep dogs on a lead.
He added: ”We’re received a large number of notifications from the public about these substances. We’re grateful for the information provided and have been trying to collect them as quickly as possible. We have also been informed that a number of dogs have become ill after ingesting this substance.”