I believe the black rat is a species of special concern and my understanding is that they are protected no matter what the listing is. Of course the regs may have changed since I last looked at them a year, or so, ago. I had the same questions when I got into some protected species a number of years ago. I was told by the DNR that I had to get permits to keep the black rat, E. fox snake, and E. box turtle.
I'm in AZ at the moment and don't have a link to the regs with me. I know they are hard to find, and also hard to read. I complain all the time. I would suggest calling the Michigan Dept. of Nat. Resources. I'll look it up when I get home anyway, but it'll take awhile.
PS: I work with the E. massasauga in the field and it is a species of special concern. I know the law reads that you can't disturb them in any way. You can't move them even to get better photos. There was a person who got a large fine a month, or so, ago for killing a massasauga in a state park. He claimed he had just protected himself, but they weren't buying it. Michigan's serious about it's wildlife laws.
>>You can keep the morphs but most states (KY, IN, CA, etc.) make mutations exempt from the "process". If an Albino/Leucistic was found in the wild it is sure to be preyed upon by something. I have been told that MI lists Black Ratsnakes as a species of interest w/ no permits necessary.? Do you have a link to the law stating otherwise? Not doubting you (even though I was told by a reliable source)- they make these laws so freakin' hard to find. There is no use asking someone because you'll get a different answer (opinion) each time.
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