The Bay of Plenty has spent more than 8.6 million dollars of locum medical specialists in the last year

The stand ins are used to fill service gaps, cover sickness and leave, and reduce surgery wait times.

The biggest spending was on the mental health department with about 3.1 million dollars.

The other two biggest spends were on gynaecology and paediatric specialists.

The Association of Salaried Medical Specialists says it shows the cost of a shortage of senior medical officials.