The Department of Conservation is calling on the public to report any orca whale sightings along the North Island's East Cape.
The Department's Dr Cat Peters says an orca whale that might be entangled in fishing lines is on the loose between Cape Reinga and Whitianga.
The orca was first spotted caught up with a cray pot, fishing lines and buoy last December.
Last week, it was sighted off the Tutukaka Coast in Northland.
Dr Peters said it's vital for the whale's well-being that it is found and cut free if needed.
"It is incredibly painful if they've got something large entangled. It also means it's really hard for them to swim, particularly in a case like this where we don't know what's left on the animal.
"Possibly it has quite tight lines [that] can cut into the skin that can cause sepsis or infection."
Dr Peters said any reports of public sightings are helpful and helps the Department best provide assistance to the whale.
Even if the orca was not entangled, locating the animal could help the Department get information on how they recover after being caught up.