Environment Southland (ES) have warned people to avoid the water in Bluff Harbour, including gathering kaimoana (seafood), following reports of a minor oil spill.

The precautionary warning is if effect for 48 hours at this stage, with ES saying they will continue to monitor the situation.

They say there are not expected to be any significant effects, and the majority of the spill has been cleaned already.

There may be a slight residual sheen on the water which could wash through to Awarua Bay.