Rotting fish is being cleared from the beach along the Coromandel Peninsula after thousands of snapper have washed ashore since New Year's Eve.

Fisheries officers are warning people to not eat the fish as investigations are underway to determine how they died and washed up on the beach.

People are being warned not to eat any fish gathered from the beach along the Coromandel Peninsula since New Year's Eve.

A Thames-Coromandel District Council spokesperson says the decision to clean up the beach was made when the fish started to rot.

The clean-up is focusing on 100m either side of Granite Wharf, north of Colville.

Rotting fish now litter beaches from Port Jackson to Fantail Bay, on the western shore of the peninsula.

Fisheries compliance manager Brendon Mikkelsen says the Ministry of Primary Industries is investigating the matter.

He says it is unlikely the fish died of natural causes and Brendon is asking for members of the public to come forward with information, along with commercial and recreational fishermen who were in the area around the time the fish washed ashore.

'We would like to hear from industry and non-commercial recreational fishers in terms of anything they might have seen at sea - likely in the late evening or early morning.”
He says some of the snapper had been taken for tested but he is not hopeful of finding any answers.