A Napier Port spokesman said the fire was on board "our tug Kaweka while at berth".
"The fire was extinguished and the tug has been deemed safe. We expect minimal disruption to our shipping operations," he said.
"Our health and safety and marine teams will be working with Maritime NZ on a post-incident follow-up."
On Sunday, firefighters also attended a blaze in vegetation at Kahuranaki, near Tukituki Bridge.
The fire was reported at 7.14pm and emergency services arrived at 7.37pm.
"It was two piles of slash burning, and we extinguished it at 9.45pm," the spokesman said.
Two rural tankers from Maraekakaho, two tankers from Havelock North, one tanker from Hastings and one from Haumoana attended the incident.
"There were no properties in danger," the Fire and Emergency spokesman said.
A rubbish fire in Waipukurau on Saturday at 6.39pm took the Waipukurau brigade 12 minutes to extinguish.
Fire and Emergency also attended a house-bus fire on Pilcher Rd, Mangateretere, Hastings.
It was reported at 6.11am on Monday.
"It was a single-storey house bus," the spokesman said.
"It was fully involved by the time we got there. There were no persons on the bus."
The fire was extinguished by a truck from Hastings and Haumoana, and a tanker.
Firefighters were also called to a shed fire in Hastings at 1.22pm on Saturday. Two fire trucks from Hastings went to Southampton St W and put out the blaze.
Meanwhile, police are appealing to the public for information about a suspicious fire at Windsor Ave, Mayfair, Hastings.
Detective Sergeant Craig Vining said police and emergency services were alerted to the fire on Saturday at 11.40pm.
"Emergency services arrived to find a hedge bordering the Top 10 Holiday Park had been set alight," Vining said.
"Several motorists stopped to see if they could render assistance."
Fire and Emergency on Saturday said fire crews arrived to find a 10m stretch of hedge on fire.
One fire crew was on scene near the Hastings Top 10 Holiday Park for an hour and a half.
One fire truck attended the scene of the fire and multiple 111 calls were made by the public, according to Fire and Emergency.
Vining said no injuries were reported.
"However, it is concerning given the fire's close proximity to where people were staying at the holiday park," he said.
"Police would like to hear from anyone who might have information concerning suspicious people or activity in the area leading up to the fire."
You can contact Police on 105 or Crimestoppers anonymously on 0800 555 111, quoting the file number 210606/0353.