Jeremy Barnum, who set up and headed the London office of credit-focused hedge fund group BlueMountain Capital, is stepping down from his post at the end of the year. He is being replaced by Gery Sampere, a New York-based founding partner of BlueMountain and the portfolio manager in charge of running the global long/short credit and capital structure arbitrage investment books.

“We mutually agreed that now was an opportune time to make the transition to new leadership in London,'” Chief Operating Officer Stephen Siderow said in a statement.

Barnum, who joined BlueMountain in February 2005 to lead the firm's expansion in Europe, previously served as head of North American credit trading at JP Morgan.