Statistics released by Stephen Byers, Labour MP for Wallsend, show that in some subject areas, more than one lecturer in five is over 55. The worst-hit subject is chemistry, with 27 per cent aged 55 and over, followed by metallurgy, with 24 per cent, and physics, with 23 per cent. In chemical engineering, mechanical engineering and architecture more than 20 per cent of lecturers are over 55.
The problem will be exacerbated by recent difficulties in recruiting scientists as undergraduates. While the proportion of school leavers going to university has risen from one in five to almost one in three in the past 10 years, the number studying science has fallen.
The figures, obtained from the House of Commons library, show that Oxford has the oldest staff of any university, with 26 per cent over 55. Aston, which specialises in science and engineering, has 25 per cent, and Cambridge and Reading each have 21 per cent.
Mr Byers said that in key subjects such as chemistry, more than a quarter of lecturers would retire in the next six years and action must be taken to prevent acute shortages. The idea of paying science staff more than their colleagues had been rejected, he said.
'With the average retirement age in the universities at 61 it is clear that there is a demographic time bomb ticking at the heart of the higher education system,' he said.
Some universities are trying to overcome the problem. The University of Manchester Institute of Science and Technology (Umist) is one of just seven universities where more than one lecturer in five is under 35. Mr Byers said that Umist's success might be attributed to the fact that its work was attractive to younger academics.
'Umist does quite interesting and exciting work which is breaking new ground, and it is probably scooping up all the younger people,' he said.
David Triesman, general secretary of the Association of University Teachers, said that within five years, half of all university staff would be over 50. Already, the figure was one in three.
'The rise in the retirement bulge is inexorable. The only rational solution is a massive drive towards new appointments, which we also need to cope with the dramatic increase in student numbers and heavy staff workloads.'
A spokesman for the Department for Education said that recruitment was the concern of the universities, not of the Government. However, recent initiatives should help to ease the situation.
'The national curriculum has made it a requirement for all children to study science. That will work through eventually. Also, we have launched an engineering bursary scheme to encourage A-level graduates to go into engineering. Ministers have said that we need to see more people going into these areas, and we have altered the university fees structure to reflect that,' he said.
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