Overall just 49 posts - including head and deputy headships - were up for grabs. The apparent slowdown in the jobs markets is now fuelling speculation that schools are increasingly relying on supply teachers, while the "brain drain" to England is increasing.
Maths, geography and general science all had five posts advertised up to January, according to the figures. But in some subjects, including modern foreign languages, there were no jobs on offer.
The figures also show full-time teacher vacancies in Wales's nursery and primary schools fell during the same period year-on-year.
From September to January there were 42 teacher jobs advertised compared with 82 previously, halving the vacancy percentage rate from 0.6 to 0.3. But teacher-training colleges in Wales report that students are successfully clinching posts as newly qualified teachers.
Attractive teaching packages - particularly from some London boroughs - appear to be luring trainees undertaking postgraduate certificates in education. But many more are said be starting their teaching careers in Wales as supply teachers at their training school.
A spokesperson for Swansea's Metropolitan University's school of education said: "Every student has a teaching job, even if it is supply.
"Of course we have trainees going to London boroughs, who actively recruit from us, but everyone has been successful in getting some kind of post.
"They have found it easier to get jobs than first expected."
Wales's qualified teaching force went down to its lowest level since devolution up to January this year, with the number of full-time teachers totalling 27,699.