At least half the birds in Steve's photograph were redheads, with greater and lesser scaup, making up most of the remainder, along with goldeneye, bufflead, and ringnecks. Longtails and scoter transit the straits as well, but sit farther offshore on calm days.
Michigan as no special regulations for the Great Lakes, with the exception that all permanent blinds on the Great Lakes or connecting waters may be occupied on first come, first served basis daily. It is also illegal to leave your decoys out overnight on Public waters; defined as any lake with a Public access site on it. You can hunt the shoreline if you set up below the high water mark anywhere along the coast where you can comply with the 450' safety zone requirement.
Steve, are you towing your layout boat, or does it sit on the tender boat's gunnels? Others have already mentioned that the Great Lakes can be rough water. Trying to hunt the Straits of Mackinac with a layout boat spread can be quite productive, but your home base choice adds quite a bit of transit time, as well as placing you in a position of having to either cross the Mackinac bridge twice a day to hunt if it is windy. Cheboygan is easily a twenty minute drive to Mackinaw City, your closest ramp site. Add another eight mile run on open water across the straits to get to the shoals near St. Ignace where most of the birds sit, or run out to the Round Island channel to hunt the protected waters on the south side of Mackinc Island. Toss in some extreme depths to hunt if you opt to try the north side of Mackinac Island in calm weather. On the St.Ignace side there is a ramp in town near the Coast Guard station, as well as one east of town by the mouth of the Carp River. There are two gravel ramps west of the suspension bridge along Brown's Marsh, as well.
If you reference Bellrose's , Ducks, Geese, and Swans of North America, you will note the various migration corridors for both diving and puddle ducks that overlay the Straits of Mackinac. You will note that most of the birds that transit this area either funnel down the St. Marys River, turning west to work down the southern coast of the UP, or head on to Saginaw Bay, Lake St. Clair, and western Lake Erie. There is also a cohort of divers and puddle ducks that migrate to Green Bay waters, either opting to fly across Lake Michigan to Houghton Lake, or work the shoreline waters prior turning south to Saginaw Bay. Good numbers of ducks congregate in Potaganissing Bay, particularly around and in the protected waters of Harbor Island, an offshore run of a little over a mile from the Yacht Haven Marina ramp on Drummond Bay. Harbor Island is a National Wildlife Refuge, with a no camping provision. Waterfowl also pod-up in its lee as well as the lee of the larger islands in the bay. Pods of birds stop to rest and feed upriver in the St. Marys River sections: southern Lake Nicolet, northern Lake George has a huge offshore pod of hardstem bulrush along the International border, Munuscong Bay, north and south of Lime Island and Potagannissing Bay. Cedarviille and Hessel inshore connecting channel waters, among the La Chenaux Islands cluster, have very good numbers of both divers and puddle ducks over the fall. There are two municipal ramps and one township ramp in this area, a pair of motels and a grocery store and gas/fast food complex.
St. Martin's Bay, east of St. Ignace also offers very good layout hunting. There is a ramp at the mouth of the Carp River for access and plenty of motels in St. Ignace as well as VRBO rentals clustered at the mouth of the Carp and a couple along the coast over to Hessel/Cedarville. One big caveat to hunting in this area is that the joint State/ Chippewa Ottawa Regulatory Authority Consent Decree mandates that the Michigan DNR Fishery Division plant 250,000 Chinook salmon for a tribal put-and-take gillnet fishery in the open lake waters off Nunn's Creek. Sault Band and Bay Mills Tribal fishers, under CORA permit, fish these waters with gillnet gangs that range from 1000' to 1500', set as surface nets or set in shallow waters. They are poorly marked. A tribal biologist (Greg Wright) lives at the walleye rearing complex near the mouth of Nunn's Creek, but, unless his attitude has changed with age, he will not provide you wit much information of their locations. When the netting first started a group of hunters lost their lives after getting tangled in a net and swamping. I would recommend you move around and set in daylight if you opt to hunt here.
West of St. Ignace and the Bridge is Brown's Marsh. Much of the marshland is now well under water due to unusually high water levels that continue to increase. What is left of Brown's Island is private land, owned by former congressman Prentiss Brown's descendants. On a northeast blow the divers clustered on the dolomite limestone shoals east of the approach causeway will shift over to the west side. This used to hold some very good hunting when I set-up there with a friend who gained permission from the island owners.
Beaver Island and its associated archipelago island "mates" also seasonally hold good diver numbers in northern Lake Michigan, but hunting out there is a logistical challenge. A former hunting partner that is now up in Alaska did quite well when he and some guys he met in his residency training took their layout boats out there.
Mullet and Burt Lakes offer waterfowl hunting opportunities as well in the Cheboygan area. I used to do very well when I lived there when I was working for the USFWS at their Sea Lamprey Research facility on Hammond Bay. Burt Lake receives a fair amount of fishing pressure in the fall months for smallmouth. Crooked Lake, further southwest down the inland waterway from Cheboygan is shallow and productive. It should hold good numbers of birds when Lakes Michigan and Huron are "rolling" during a storm, but you will likely be challenged by local law enforcement, courtesy of the multi-million dollar home owners that line its shoreline. There is some shoal water off the southeast corner of Bois Blanc Island as well that should hold some birds, but when they are concentrated there the run out will be a rough ride!
Carp Lake, by the town of Carp Lake is shallow and close enough to the open waters of the Straits to pull and hold birds. It gets hunted hard. Yes, it's been renamed, but I am not PC enough to use the new moniker. French Farm Lake is a bog dystrophic lake that is an occasional roosting spot for waterfowl. I scouted it numerous times to find very few birds when I lived down there. Cecil and Trails End Bays, west of the bridge will hold some birds on infrequent easterly blows, but ramp access is not very good.