Bird-Smith had his first national success in 2008 when he won the Australian youth title. Junior-level titles followed the next year and he also made his international debut, placing eight at the 2009 World Youth Championships in Athletics. He repeated as road and track national junior champion in 2010 and set an Australian junior record of 41:32.36 minutes for the 10,000 metres race walk while finishing fifth at the 2010 World Junior Championships in Athletics. He also made his debut at the 2010 IAAF World Race Walking Cup, but was disqualified from the junior race for foot-lifting. He improved further to 41:02.18 minutes in 2011 and also set an Oceanian record of 40:56 minutes in the 10 km road walk discipline to win the exhibition event at the Oceania Race Walking Championships.