Stuart Hogg, Adam Ashe, Henry Pyrgos and Greg Peterson have all signed new deals but Mark Bennett, Alex Dunbar, Tommy Seymour and Josh Strauss are all out of contract this summer.
Speaking to BBC Scotland, Mike said: "It's difficult with the rugby contracts, you don't often get contracts longer than two years so it seems that every year there's half the squad who are pretty much out of contract. We'll be working hard to keep the guys here.
"There's a lot of money being thrown around in England and France but the product that Glasgow can give - the coaching team, the crowd that we've got, the fact that we beat Racing home and away, we're playing against the best teams in Europe and doing well - hopefully that's a big pull for the guys as well."
Dave Rennie will replace Gregor Townsend as Glasgow head coach this summer. Gregor is leaving to become Scotland head coach.
"Dave Rennie's going to have a say in what's happening here," said the former Scotland skipper.
"He's watched a lot of the games from the last two or three seasons to get a handle on what players we've got here and what he likes and what he could potentially bring in."
Thngs are beginning to look a bit brighter on the injury front at Scotstoun. Greg Peterson is nearing a return to the first team following long-term injury, along with Tjiuee Uanivi, Scott Cummings and Richie Vernon.
"We're expecting to see them back in the next two or three weeks," explained Mike.
"They're taking part in all the non-contact stuff so they're progressing well.
"Pete Horne's showing good progress. He's another couple of weeks before he can step up and we'll see how he reacts to that.
"It's good timing for us. We've got some good quality players coming back. They'll be in a good place when they come back in.
"We've got some big games coming up and some big games during the Six Nations as well once the guys are away on [Scotland duty]."