The comments come after polytechnic chairman Kevin Cosgrove announced the institution was exploring its options after it recorded a financial loss of $1.6 million last year and is facing a projected loss of $2.1 million this year.
It was also forecasting 328 fewer equivalent full-time students than budgeted for this year.
"Aoraki Polytechnic is responding to changes in tertiary education that require us to focus more on our core operations," Mr Cosgrove said.
As part of this, the polytechnic, which has campuses in Timaru, Ashburton, Oamaru, Christchurch and Dunedin, had appointed independent adviser Malcolm Inglis to look at its business model. Mr Inglis would report back to the council on its options in December.
TEU southern region organiser Kris Smith said the council had failed to inform staff of its plans and they only learnt about the appointment of Mr Inglis through the media.
"We are aware that something needs to happen ... but we think it is important to keep staff in the loop," Ms Smith said.
The union had asked the council about its plans, including whether it was looking at a merging with other South Island polytechnics, but was yet to receive a reply, she said.
"That sends a very negative message to staff about the value of their knowledge and any thoughts on the future that they might have."
It was "madness" for the polytechnic not to tap into the ideas of experienced staff members.
Mr Cosgrove said it was too early to say what the options for Aoraki Polytechnic's future were, but that they would be discussed with all stakeholders, including staff and the community.
A spokesman for Tertiary Education Minister Steven Joyce said last month the minister was "aware" the polytechnic was having discussions with "a number of South Island" polytechnics about collaborating.
"It is too early to contemplate a particular outcome from these discussions, and the minister expects to receive advice from Aoraki before they make any changes," the spokesman said.
