Five of the hospital's six technicians are members of Apex - a union representing scientific medical staff.
A series of strikes have been held around New Zealand after the union and DHBs failed to find agreement on staffing issues.
Southland Hospital is the only southern region facility which has received notice of strike action.
Southern District Heath Board specialist services director Patrick Ng said acute theatres and other services at Southland Hospital - including the emergency department - would function as normal.
''As a result of the strike the DHB may need to postpone some elective surgery today,'' he said.
''However, we still have enough staff to proceed with a number of surgeries.''
Patients booked in for surgery today had already been informed their surgery might be postponed at the last minute, he said.
''They will either be contacted by phone or advised on the day if their surgery is being postponed.
''We appreciate the inconvenience this may cause but our priority is on ensuring the safety of our patients.''
Apex national secretary Deborah Powell said issues regarding safe staffing levels, professional development and recognition of clinical responsibility remained to be settled by the Southland staff.
The union had asked for the SDHB to employ one new anaesthetic technician trainee each year at Southland Hospital, to ensure adequate staffing levels for the future.
''They are also asking for a minimum of 9 FTEs on the roster to allow for adequate sleep after on-call and call-back duties, and professional development funding so they can meet the Medical Sciences Council's requirements,'' Dr Powell said.
''This strike is also about ensuring safe healthcare for Southlanders.
''It is a common occurrence for paediatric MRIs and paediatric dental surgeries to be cancelled because of insufficient anaesthetic technicians.''
