The letter's author, Southland Federated Farmers sharemilker chairman Jason Herrick, said they had exhausted all avenues to employ New Zealanders to fill the gap.
He explained that with no change it would not just be a human welfare issue, it could become an animal welfare one too.
These stresses were compounded by winter grazing regulation anxieties, as well as attractive offers from Canada and Australia, where a minimum salary of $75,000 was on offer.
"I'm really feeling sorry for them with the whole situation that's coming. I really think there will be some catastrophic events if the Government doesn't change their ways."
It was hoped managed isolation and quarantine spare spaces could be allocated to fill those vacancies.
Since he had written his, a letter-writing campaign had begun of hundreds of pleas from those in the industry asking for help.
One, written by Michael Prankerd, was shared to social media and detailed the stress southern farmers were under.
"There has been a sharp rise in suicide on farms throughout the South Island in the last 12 months and many of these have been farm assistants, not employers."
The campaign concluded at the end of last week.
The letters were also sent to Prime Minister Jacinda Ardern and Immigration Minister Kris Faafoi.
A spokesman for Mr Faafoi said the minister was aware of concerns raised in the dairy sector and had been discussing the issue with his colleague, O'Connor, who had been liaising with the dairy sector to understand the exact scale of the problem.
"That information is feeding into work to determine what can be done to address concerns within the constraints of current Covid border restrictions."
He said the Government was looking to have more to say in the next few weeks.
Herrick had not yet received a response to his letter and said he would send another.
Although the Otago Daily Times approached him two weeks ago, O'Connor did not provide comment or a response.
