Morgan Stanley suffered its first high-level defection since paying out bonuses this week with the resignation of Jon Anda, co-head of global capital markets.

Mr. Anda, 48, is joining a firm being formed by former Morgan Stanley banker Joseph Perella, signaling the start of poaching expected by two groups of top executives and bankers who left the firm in mid-2005.

Mr. Perella and the firm’s former investment banking chief, Terry Meguid, left Morgan Stanley in mid-April 2005, after then-chief executive Philip Purcell replaced three other executives, including institutional securities chief Vikram Pandit and former equities division chief John Havens.

When John Mack replaced Mr. Purcell as CEO, Messrs. Perella, Meguid, Pandit, and Havens refused to return and work for Zoe Cruz, who had backed Mr. Purcell. But Mr. Mack resisted being pressured to sideline Ms. Cruz, who remains the firm’s acting president.

To make it tougher for rivals to poach the firm’s top talent, Mr. Mack took steps late last year to lengthen the period of time in which bankers must wait before joining a competing firm. Bankers had to sign the more stringent non-compete agreements in order to receive their bonuses, which were paid on Monday.

Mr. Anda is the first of numerous bankers expected to join firms being formed by the Perella-Meguid team and another being launched by Mr. Pandit and Mr. Havens.