A ministry spokesperson said four people had so far been prosecuted and sentenced in relation to illegal dog tracking collars nationwide. Scarfe was the first prosecution in Hawke's Bay.
New Zealand Pig Hunting Association president Warren Petersen said his organisation did not advocate bringing in the illegal Garmin trackers but they were "by far" the best available.
Scarfe broke the law so he would have to accept the fine and prosecution, Mr Petersen said.
"We've been dealing with this issue for two-and-a-half years and we actually imported a Spanish [tracker]," he said. "It is as good as Garmin, but we can't get anyone to take it off our hands to distribute it.
"We have had three outfits take it and trial it. They have said there's nothing wrong with it, but it is just too complicated.
"We've been to Garmin and asked them if they would change and put it on to a legal frequency and they said they're not interested in our market."
He said the company could sell up to 30,000 units within a single US state.
"It's simple to use and it has got a good screen and [topographic] map on it. There are other ones out there - we just call them beepers. It beeps and tells you where your dog is, but doesn't tell them if it is in a gully or not. It just tells you the dog is 100m away - well, is it in the neighbour's pig pen or what?
"We don't want anyone to get hurt and if we can possibly solve the problem without anyone getting hurt that has got to be good, doesn't it? I would really like to be able to somehow legalise the Garmin. I'm in negotiations with the police ... They've indicated they would be keen to come on board."
The court heard GPS data downloaded from Scarfe's units showed one or both of the devices had been used on numerous occasions in June and July last year.
Ministry prosecutor Jessica Blythe said the "serious" offending was part of a "worrying increase" in the use of such devices.
"The radio frequencies are used by a number of industries but in particular forestry, transport and logging companies," she said. "These devices can interfere with emergency communications in those sections.
"There is potential for emergency lines to become blocked so generally the person trying to make contact cannot hear anything. The safety issues and risks that can result from this are significant, particularly in regard to the forestry industry where these radiocommunications services are relied upon."
Scarfe's lawyer, Peter Austin, said the dog collars were bequeathed to his client some years ago. Scarfe was not "particularly savvy" regarding the law around radio waves," Mr Austin said.
Judge Richard Watson said the concern the ministry had was in regard to the interference with other radio frequencies and the safety aspect associated with having clear communication via radio networks.
"Safety within the forest is a big issue, there have been a number of deaths recorded, and if workers cannot use radio bands, due to your interference, that is a safety element that is no longer available to them."
