The Englishman, a 6-foot tall 27-year-old central defender, joined the I-League runners-up side after spending four years at Swedish side Gothenburg Athletics and Sports Association, popularly known as GAIS.
"Mike (coach) has spent a lot of time analysing videos of Calum and we are very pleased to have Calum sign with us. He comes with a lot of experience and should bolster our back line," said Pune FC Head Operations, Chirag Tanna.
"I'm happy to be here. The emphasis of Pune FC is on the youth system and it's very interesting. They want to bring young players into the main team and it is very exciting," said the player.
Calum's inclusion makes him the second foreign player signed at Pune FC this transfer window after Spanish-born striker Raul Fabiani. Both join playmaker Douhou Pierre to fill up three of the four foreign slots for this season.
Calum is also the fourth foreign defender in the I-League era for Pune FC, after Sergey Tokov (Uzbekistan; 2009-10), Chika Wali (Nigeria; 2009-10 & 2011-13) and Lamine Tamba (Senegal; 2010-11).