He started detecting three years ago, and said it has been an easy hobby to get into.
"It's relaxing. It's like treasure hunting. You just don't know what you're going to get".
He says there are detectorists scattered all across New Zealand. And the hobby has become more popular, thanks to a recent BBC comedy series The Detectorists.
He finds and removes a lot of rubbish, and insists he's careful to leave things the way he found them.
"Pretty much looking for coins and relics and all that sort of stuff.
"For me, it's about finding lost history.
"Yeah, I love finding things from ... especially the war - World War 1, World War 2. You learn so much".
"Mainly coins, yes. But every now and then, you find relics.
"Late last year I found an 1800s padlock in a river, fully intact. Brass is all still nice and shiny."
When he unearths a valuable item that has an engraving on it, he makes every effort to track down the owner.
"You've got to be careful where you detect.
"There's a lot of historical land and stuff like that, which is a big no-no, a lot of places you need permission for."
Digger Mike hopes to uncover more historical artifacts to reveal some of the in-depth stories from Canterbury's rich history.
- By Geoff Sloan, made with the support of NZ On Air