Bird has been editor since late 2002, after joining the magazine in the mid-1990s on a work experience post. He then spent time as reviews editor and as a freelance writer.
Bird is leaving to pursue writing and music interests. He said: "The magazine is in great shape, with big plans and a super-talented editorial team and I'm really excited to see what the next editor can bring to the party."
In the most recent set of ABC figures, Kerrang! was down 9.6% for January to June 2004 to 62,591. IPC Media weekly rival NME was down 3.5% for the period to 70,014.
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