As interim MD, Birley will 'hold the fort' until the agency finds a replacement for outgoing MD David Hargreaves. Hargreaves is leaving to take a role in Bite's US operation, leading its 100 staff.
Bite global CEO Clive Armitage will move back to the UK this summer, partly to help in the search for a permanent successor.
In a separate move, Bite has hired guidebooks website Itchy Guides founder Ruby Quince as head of digital. 'Quince will build on the success of Bite being known for doing more than just "blogger relations" but creating digital content (games, applications, widgets, virals) which are then distributed on the web,' said Hargreaves.