Bay Kiwifruit growers are uncertain what impact the discovery of a Queensland fruit fly will have on the billion-dollar industry.
The Ministry of Primary Industries is investigating the discovery of a single male Queensland fruit fly in a surveillance trap in Whangarei.
It was collected on Tuesday and formally identified on Wednesday.
Chairman of Kiwifruit Vine Health and local grower Peter Ombler said only one male fruit fly had so far been found.
The find showed the surveillance system for the pest was working and "there is not yet a breeding population," he said.
"We are stamping out the problem before it arises, this has happened previously but we have always dealt with it."
There were a number of ways the fly could have gotten into New Zealand, he said.
"It could have been brought in on a piece of fruit or a vegetable, through an airport or a seaport."
He was uncertain what it would mean for the industry.
"Where it comes from, kiwifruit are not grown, we don't know if kiwi(fruit) is attractive to it. I am uncertain what the consequences might be," he said.
"I would have thought the flies would be more attracted to a summery fleshy fruit.
"Any orchardist should be concerned but I am not going to lose any sleep over it at the moment."
Somerfield Berryfruit Farm owner Richard Somerfield said the find was potentially disastrous for fruit and vegetable farmers all over the country.
"We all have to be worried."
"It's pretty important, it has to be stopped ASAP."
"I hope they swing into action, they have to find a way to control it."
Horticulture New Zealand president Julian Raine said the New Zealand horticulture industry was "holding its breath" while it waited to find out if there were any other fruit flies found.
"This is an anxious time for all growers and the whole horticulture industry."
Mr Raine said increased trapping and monitoring had begun and urges people in the area to comply with the MPIs needs.
"Looking inside the zone and being able to go into home gardens to see if there are any other contaminations."
He said the risk to the $4 billion New Zealand horticulture industry is two-fold.
"First, is the destruction caused by the pest and on-going cost of attempting to control it and second, the cost of international markets closing to our products.
"Worst case scenario, if other flies were found, would be the potential closure of the export market overnight."
But he said they would be working with the MPI to make sure that does not happen.
"We will work together to eradicate them if there is more than one."
Zespri could not be contacted for comment.