''He was highly regarded in the community and highly trusted and he breached all of that,'' Mr Garnham said.
The thefts from Criffel Deer Farm appeared to have occurred between mid-2009, when Mr Garnham promoted Herd from assistant farm manager to manager, and September 2011.
"It was only on his promotion following retirement of the then farm manager that he had the opportunity to do these sorts of things and I simply do not believe that he could have done any of these things on his own.
"He could not have managed these thefts without the assistance of others, knowing assistance.
"I'm in no doubt that there were other people involved ... it could be a number like a half a dozen [other people] or something of that sort."
In November 2011, when the police investigation was well under way, several sources in the Central Otago-Upper Clutha farming industry told the ODT a large-scale rustling ring had been operating for several years in the area, involving a large organised network of people.
Mr Garnham said he would "absolutely accept" that information, and he was disappointed "some of the parties" had refused to provide information about the involvement of others that could have led to further prosecutions and recovery of stock and money.
They had "clammed up ... to protect others", he said.
Furthermore, Criffel Deer Farm's losses were "vastly in excess" of the $300,000 worth of stock and other items that Herd and Mr Hawkins were charged with stealing and which Herd pleaded guilty to, Mr Garnham said.
"Quite apart from the stock and other items that these guys were charged with, there are quite significant numbers of stock that are unaccounted for from our farm ... more than these guys were charged with ...
"This is a deposit on what we have lost.
"I have also been given information from third parties as to how and where some of our other stock has been removed or stolen or otherwise dealt with."
"However, that's a different issue from saying that I have sufficient evidence to prosecute anybody else at this point."
Mr Garnham said rustling of stock, particularly capital breeding stock, had "huge" consequences for a farm, as it could lose several years of progeny and revenue well beyond the value of the stock stolen.
"It's quite an insidious form of theft."
Criffel Deer Farm was still recovering from its losses.
''We have had to reinvest very substantially in the farm and we have almost rebuilt the farming operation.
"Another season will get us there and we have enjoyed very considerable goodwill from a number of the suppliers and contractors that we deal with, as well as some excellent staff to help us get there."
Criffel Station owner Jerry Bell and Mr Cochrane both declined to comment on Herd's sentencing.
Attempts yesterday to contact Mr Hawkins and Detective Alan Lee, who worked on the case, were unsuccessful.
The Herd charges:
• 16 of stealing a total of 632 deer valued at $278,255
• 2 of stealing 14 trophy stags ($14,600)
• 2 of stealing 126 sheep ($19,800)
• 6 of stealing deer velvet ($10,164)
• 1 of stealing hard antler ($1500)1 of stealing drench ($7630)
• 1 of stealing 10 tonnes of barley ($3200)
• 3 of stealing farm and office equipment (about $3000)
