The King Country region appears to have escaped relatively lightly from a major oil spill last week.
More than 20,000 litres of oil spilled into the Awakino River after a truck crashed in the Awakino Gorge.
About 3000 litres of the truck's load was recovered at the site and a further 3000 litres sucked from the river, but the rest flowed into the sea.
Waikato Regional Council and the Department of Conservation say birds were affected, but not badly enough to be worth catching them to get the oil off their feathers.
People catching fish or shellfish in the area are advised to make sure their catch does not smell of oil before eating it.