Banks do not need specialist office in large numbers. Hence we may not be aware of the large scale tests as seen for PO / clerical recruitments.
Banks may need Law Officer, Civil Engineers, Technical Officers, Security officers, etc for its various needs. They may not be needed at branch level, but to be stationed at Regional or Zonal controlling offices and at Head Offices. Some banks may need Doctors, IT specialists for development works and in some cases some very special officers in finance related matters.
For recruitment banks will call for candidates with such specific qualifications and experience related to relevant field. Hence the notifications may be small and brief with reference to the bank's website for details. There will be written test and interview or just interview depending upon the RBI guidelines existing and the exigencies at that time.
There was a time when banks recruited Agricultural Officers and Veterinary officers in good numbers. Now such officers are taken only in less numbers as specialist officers as and when needed. Generally specialist officers are appointed at a higher level i.e at middle management level.