Colleges are recruiting high-earning managers at a far greater rate than new teaching staff, an analysis by the University and College Union (UCU) has revealed.
Between 2006 and 2008, the number of staff in posts earning more than 50,000 grew by a third, while the number of teachers rose by just 2.8 per cent, the union's breakdown of official figures shows.
UCU carried out the analysis after members raised concerns at last year's conference that resources were not reaching frontline teaching staff and that the pay divide between lecturers and managers was growing.
The trend of growth in higher-paid management roles has come despite some colleges cutting back. For example, Manchester College of Arts and Technology reduced its highly paid staff by 27 per cent before its merger in 2008.
Newcastle College saw the greatest growth in highly paid staff, with numbers rising from 18 to 45, but that period saw a dramatic expansion with the acquisition of part of the private training firm Carter amp; Carter and the merger with Skelmersdale amp; Ormskirk College. It also saw teacher numbers rise by nearly 12 per cent.
But others saw teaching staff decrease by up to 8 per cent while the number of high earners grew.
Barry Lovejoy, head of FE at the union, said: "UCU is not against people being properly rewarded for doing their jobs well.
"However, colleges have to be upfront about why so many more people command such high salaries out of taxpayers' money as the axe falls with devastating effect in other areas of further education. Some may also question why college principals have continued to enjoy percentage pay rises more than twice that of frontline staff.
"Further education is facing huge funding pressures at the moment, with thousands of jobs and courses at risk. Many of our members are still being paid less than their equivalents in schools, and it is important that colleges are open with their staff and the public when it comes to pay."
Peter Pendle, general secretary of the Association for College Management, said that despite the greater rate of growth, it equated to just 100 extra higher-paid managers across the 30 largest colleges surveyed. Some of them may also have teaching roles, he said.
But typically colleges were reducing the number of managers, Mr Pendle said, and the figures may conceal many earning less than 50,000 whose jobs are disappearing.
"Those that remain have more responsibility, more work and get higher salaries," he said. "Our experience, increasingly so, suggests that colleges are restructuring and losing management posts."
Evan Williams, director of employment at the Association of Colleges, said focusing on the largest colleges may mean that the results are not representative. They included a disproportionate number of London colleges, whose staff normally receive higher pay.
He also questioned the union's decision to have a threshold for "highly paid" staff in HE at 100,000 a year - double the figure it considered a high wage in FE.
Mr Williams said: "Colleges are independent organisations where a governing body is responsible for setting senior staff remuneration, and these governors are fully aware that their institutions are publicly funded and subject to rigorous audits. They use their funding wisely.
"Some colleges listed in the report have been subject to mergers and acquisitions, which create exceptional circumstances. It is also important that these complex, multimillion-pound organisations are professionally run and the pay grades reflect the need to recruit the best."