The 20-year-old Wales U21 international has made two appearances in the SkyBet Championship for the Blues, both at the end of last season, and has now been sent to the One Call Stadium to assist his development having recently signed an extension to his deal at St Andrews.
And the midfielder says he is looking forward to the challenge.
He said: “It’s great to sign for a club of this stature.
“I’ve been at Birmingham now for quite a long time and it’s just great to get out on loan and get some experience at a club like this and hopefully play a lot of football this season.
"The coaches in the academy at Birmingham have helped me develop into the player I am today and to be playing for the U23s, then to get a couple of games at the back end of last season for the first team.
“That whetted my appetite for regular first team football and gave me a boost to play more games and I can’t wait to play men’s football now.”
Stirk says he bent the ear of another new Stags signing, Ryan Burke, before making the move north, the pair having played together at Birmingham prior to Burke’s release earlier this year.
Stirk said: “I’ve played with Ryan since I was 16 and in my scholar days at Birmingham and he’s a great lad.
“I spoke to him on the phone a couple of days ago and he said what a great club it is, how he’s really enjoying his time here and that the gaffer has been really good with him, so I can’t wait to get working with him as well.”
In terms of what Stags fans can expect from their new man, Stirk is clear on his role in the team.
He said: “I play in a defensive central midfield role but I like to get the ball down and play forward as soon as I can after transition, or play into the striker’s feet as well as going for balls in behind and giving them opportunities. I always give 110 per cent every game and work hard to win the ball back.
“I can either play at the bottom of a diamond in front of the back four, or left side of a three or the right side, I don’t mind.
“Our coach at Birmingham likes the diamond as well so I know the roles well so hopefully I’ll fit in perfectly.
“The people I’ve spoken to about League Two have said it’ll be the next step up for me in terms of physicality so I’ll need to be strong, but I’ll do that and get around the pitch to put challenges in, win second balls and win headers too.
“I’ll have to come in and work for my place and if I get a chance I’ll take it. I’ll have to show the gaffer what I’m about and try to impress him enough to get a start.”