That's correct, Tiger trout. A very rare hybrid of a male Brook Trout breeding with a female Brown Trout. The Tiger Trout is sterile and can be caught on the Maple River. I have seen three, all of them about 9 inches long, in 50 years of fishing.
In Michigan there is not a planting program for the Tiger Trout and they are all natural occurrences. Their explosive take of the fly combined with an aggressive fight marks them. I was amazed as my fishing partner could tell the second one hit that the fish was different. He was a great Brown Trout fly fisherman who fished many afternoons with me for my favorite trout the Brook. So when the trout hit, his experience could tell it was a Tiger Trout. Amazing to watch him fight the fish and asking me to ready the camera for a photo. Sure enough a "Tiger"!
Not much information about the Tiger Trout is available at this latitude. It's longevity or numbers are unknown. Tiger Trout are raised in some states and are use to clear out some unwanted species of fish in trout waters. Due to their aggressiveness and inability to procreate the Tiger Trout is perfect for the task.
My experience is lacking on the trout, so is the MiDNR experience. I don't know what to tell you other than if you do land one the Tiger's pattern will surprise you. To me it looks more like a leopard than a tiger. Whatever, it is rare and if you catch one take a very good look and a photo, you may never catch one again.