The public in Northland and Auckland are being asked to keep their eyes peeled for an orca which is tangled in a rope with a buoy attached.
The orca got caught in a crayfish line on Monday and efforts to free it in Whangārei Harbour yesterday were unsuccessful.
Dr Ingrid Visser from the Orca Research Trust and Whale Rescue said if people spotted the animal and his pod they should call 0800 See Orca.
'We're very very worried about him but we just need the public to be aware that they can't disentangle him themselves, it .... [takes] specialist equipment, and we have special training for it as well."
Dr Visser said a team was on standby and ready to deploy when they get word about where the orca was.
She said the law does not allow the public to go within 50m of the animals, and as he was struggling to hunt as it was the last thing he needed was for people in boats to interfere with him.
She said the line was cutting deeper into him and would eventually sever his fin.
"And of course he could either bleed to death or he could get an infection and die from that.
"So it's incredible painful for him and it's going to be a very slow and drawn out death."
She said by the end of the week it was possible the pod could be as far south as Tauranga right up to the tip of the North Island.