Good topic...

Skamania stocking was undertaken in Ontario by the SSA.
The Saugeen had a minimal Skamania run as a result from strays from Michigan. This became an egg source for the SSA who trapped them in the summer at Dennys, and held the fish in ponds on SSA hatchery property until they became ripe in late winter. These fish were usually given a shot in order to induce them to become ripe in order to strip the eggs. Very intesive process. I recall watching the whole ordeal at the fishway, ponds and hatchery each year during the program.

Mich and Ont no longer stock Huron or Gbay with them...and they havent for well over a decade +.

Could you catch a stray Skamania from Lake Michigan where they are still stocked?
Yes, possible, however, chances are very very slim, and to be able to positivley ID the fish without fin clip references makes it that more impossible.

The "archive" link Kyle posted is very accurate.

In terms of ID for Skamania strain summer runs.
They were long, lean fish. Carried specific clips, had big eyes and tails with very thick wrists. Yes, they jumped alot, as do most steelhead caught in warm waters. Yes they were silver, as most steelhead are when caught outside of spawning and wintering phases. They were very strong and large...same deal with the average steelhead. Big heads...sure, most "male" trout and salmon have big long heads in comparison to females.
I caught plenty while tagging along with my father on numerous trips when I was younger. Cannot say I have positively seen one in over 15 years. Since then, every catch claimed to be a Skamania appears to just be a run of the mill steelhead. If I had 5 dollars for all of the times I have heard, "hooked a fish that jumped 4ft out of the water, hit down 40ft over 100, must have been a Skamania"...i would be looking at some very attractive investments. In late May, there were a few steelhead caught off the harbor in Owen Sound. These were dropbacks that were obviously stuck up stream a little later than usual. They were very long, lean and already starting to silver up. They looked like worn out dropbacks that needed to hit the big lake. When I stopped by the cleaning station a fella with 2 in hand clamied they were big Skamanias because he caught them in the river in late May and they jumped like crazy. A couple seconds on the cleaning board and he found out they were silver droppies which were starving and white as snow inside in terms of fillets.

Nick asked "can you provide any guidance on the different variations we encounter in silver, big-water Rainbows: solid black or blue, mottled green, etc?"

They are creatures that blend in with their environment. Steelhead can appear to exhibit all kinds of colourations along their backs. Each fish is different, and each fish has the ability to adjust, usually to their surroundings. After handling 100's of fish at the Saugeen this fall, winter and spring, it becomes apparent that every steelhead is slightly different. Some carry lots of spots, while others appear to lack all spotting. Some days they are blue backs, the next day they are grey or green. Look at all the photos posted on here during peak steelhead times....no fish is ever the exact same. This is no different offshore where they all tend to be silver, but the backs can be green, blue, grey or black. As soon as you kill one that was caught offshore the colour change really begins. We boxed a 2 man limit off of Southampton last week. Each fish hit the deck silver and blue. When we pulled them out of the cooler 2hrs later they all looked different. 2 were royal blue, 2 were green. This is one of the reasons I think steelhead are super cool as they always suprise me.