Alistair Johnston, president of the Headteachers’ Association of Scotland, warns of a crisis at the top as staff turn their backs on promotion. “It’s a gut feeling and rather difficult to measure. But there has certainly been no rush to headships in either the primary or secondary sector,” Mr Johnston said. This comes at a time when there is increasing emphasis on the importance of the quality of heads in raising standards.

Mr Johnston thought it significant that 700-pupil Berwickshire High, “a normal rural comprehensive school”, is readvertising for a head, the first time he can remember such a necessity in the Borders. Kelso High, where he is head, had only two applicants for head of maths and is now readvertising.

Rena Mitchell, president of the Association of Head Teachers in Scotland, says the worry is that “significant numbers of experienced primary heads are leaving before normal retirement, so much so that I am beginning to feel like a dinosaur”. South Lanarkshire, her employer, lost 23 out of 124 primary heads to early retirement last session, although the council is said to be happy with the quality of the applicants for these posts.

The issue has been highlighted by a major survey south of the border, published yesterday (Thursday), which reveals that 1,000 schools have started the academic year without a permanent head.

In what is described as “probably the worst recruitment crisis in living memory”, the survey by the National Association of Head Teachers found massive rises in vacancies combined with reductions in applications and an increasing need to readvertise posts. A total of 2,516 vacancies for primary heads were advertised between September 1 last year and August 1, a rise of 29 per cent. Of these posts, 350 had to be readvertised. Vacancies for secondary heads also rose, by 24 per cent.

Vacancies for primary deputy heads increased by 47 per cent this year and for secondary deputies by a massive 52 per cent.

The situation this year has been exacerbated by the number of teachers leaving before changes to the pension regulations came into effect on September 1. About 2,000 heads and deputies are thought to have left for this reason.

Mr Johnston believes that the upheaval of moving house and finding jobs for partners makes potential heads think twice. He did not believe the extra responsibility of devolved management was a key factor. “It is more to do with the general pressure that comes from the expectation that schools should be accountable and responsible for everything,” he said.

Mrs Mitchell agrees that headships are not as attractive as they used to be. Her depute at Forth primary is seconded to a temporary headship but has not applied for any vacancies. The extra salary would not compensate for the “hassle, stress and workload”, she said.

But salary levels, while important, are not always the critical factor, Mrs Mitchell feels. “The confidence to become a head and the desire to do the job are also relevant. A wish to influence and contribute to children’s learning is another motivation - there are still such people around.”