Silver Salmon is the Goldilocks of Salmon:
Silver, also called coho salmon, is the in-between salmon: not too big, not soo small, fatty but not the fattiest, firm but not the firmest -- pricey, but not nearly the priciest salmon you can buy.
Silvers are caught from Oregon to Alaska, and typically run starting in June and last until September. They are a pretty chrome in the ocean and when they first appear in rivers, but turn deep red when they head upstream to breed.
Once they turn, or develop that crooked mouth you may have seen, coho salmon are basically inedible.
Most silvers are between 8-12 pounds, although they've been caught beyond the 30-pound range. Their meat is orange, like most salmon, from the krill they eat at sea. A coho will not be as orangey-red as a sockeye or a king; it'll be about the same color as a farmed Atlantic salmon.
Eating wise, silver salmon have less fat than sockeyes or kings, but more than pinks or chum salmon. This means a coho can dry out faster than the other species.
Coho salmon are a perfect poaching fish. Their relatively low-fat content benefits from the gentle cooking, which keeps it moist. A side of coho is also perfect for one of those poaching pans the fancy stores sell.
I would not smoke silver salmon if I had access to king or sockeye, but silvers are perfectly good smoked. You will need to watch your heat! Smoke silvers slightly cooler than kings or sockeyes so what fat they have does not run out.
Silvers do well as gravlax, the Scandinavian cured salmon, and they are great as sushi -- if you've bought it frozen or put it into the deep-freeze for a few days.
My favorite way to cook silver salmon is to slice it into cutlets, then lightly dust it with flour, then saute it in walnut or olive oil.
Maybe then serve it with a French rouille sauce. Silvers benefit from this sort of cooking, while kings might feel too greasy done this way.
You can also slice the skin of a coho (or any other salmon) into thin strips and fry them slowly until they're crispy. This is a great way to enjoy a healthy part of the fish -- it typically has a thin layer of fat on the underside, which is loaded with healthy omega-3 fatty acids.
Bottom line: You can use silvers in any typical salmon recipe, but definitely, think about poaching or sauteeing when you find yourself with some.