Maritime New Zealand, the agency responding to the incident, said Thursday it observed a light sheen of oil stretching roughly 6 miles from cargo vessel Rena, sinking off the country's northern coast.
Rena struck a reef in the Bay of Plenty in October, dumping around 2,000 barrels of oil into the sea. MNZ managed to get most of the oil out of the stricken vessel by December.
Early this week, New Zealand authorities said they were anticipating 15-foot waves in the northern bay by Friday. Aerial surveillance of Rena found rough seas have broken up the sheen to the point it's no longer visible at the wreck site.
MNZ had expected some of the oil to start reaching area shores by Friday, though observation flights reported no visible patches of oil headed to area shores.
"Oil spill response teams remain ready to respond to any fresh oil coming ashore," the agency said in a statement.
A containment boom is in place along much of the northern coast, MNZ added. Some oiled birds were recovered as well.