The average pay of male academics in the UK lags about £10,000 behind their American counterparts, according to research.
Philip Stevens of the National Institute of Economic and Social Research concludes that although the numbers of academics leaving the UK is relatively small, "there is a strong pay incentive for academics to migrate from the UK to the US".
Dr Stevens found that academics at the middle of the income scale in the US enjoy higher earnings than 75 per cent of UK academics.
For female academics, the earnings gap widens during their careers - starting at £3,000 for 30-year-olds, reaching £7,000 by the age of 40 and closer to £10,000 on retirement.
But for the top ten highest earning academics, the gap in average pay spanned £45,000 in the UK to £69,000 in the US.
Dr Stevens' research also underlines that academic pay on both sides of the Atlantic lags behind graduate earnings generally.
In the UK, academics at the age of 30 earn 72 per cent of average graduate earnings. By the age of 40, academics earn 79 per cent of the average salary and 86 per cent by the time they turn 50.
Dr Philips said: "Given that the US seems to be the UK's main competitor, one needs to address the issue of the US possibly taking our best and brightest academics.
"If the disparities are greatest at the top end of the earnings scale, it may also create a negative feedback effect lower down the scale in the sense that UK universities could find it difficult to attract other levels of staff. One needs a critical mass of quality - big brains in departments help attract the young guns."