Salmon caught in saltwater or near the mouths of freshwater streams will look a lot different from those that have spent many days in freshwater. They undergo a transformation as they near the spawning area where they will mate and die. They typically start out as a blue or metallic silvery color, then fade to a deep red or green as they near the end of their lives. For the best flavor, fight and appearance, the key is to catch them well before they've reached the spawning stage. It is also bad ethics to harass a fish near the end of its life in its breeding grounds.
Run timings vary from stream to stream, but quick research on the part of the angler will produce big benefits, since salmon have a remarkable sense of timing. Check with state biologists, guides and tackle stores for the timing of a specific run. These fish tend to return to their spawning streams at the same time each summer, give or take a few days. King salmon start hitting Alaska streams in mid-May. Kings and reds dominate Alaska fish streams in June and July. Pink and silver salmon tend to show up in late July and August.
King (chinook) salmon
King salmon, the giants of the species, are well-named. Finning out of their freshwater nurseries into the Pacific Ocean at age 1, they are only about 4 inches long. But after four years at sea, these predators return to spawn, having bulked up to an impressive 25 to 60 pounds.
Most kings won't exceed 40 pounds. But on the world-famous Kenai River, home of the largest kings ever caught by rod and reel, anglers bag "hogs" of 70 and 80 pounds. The world-record sport-caught king was hooked in the Kenai River in 1985. It was a shade over 97 pounds.
Kings usually can be distinguished by their size alone. A trophy Kenai king will exceed 4 feet in length. But anglers sometimes do hook younger chinooks, known as jacks, which can weigh 10 to 20 pounds. A fresh king salmon will have a blue-gray back with silvery sides. One readily distinguishable marking is the series of small black spots on its back, dorsal fin and tail. Kings also have black mouths and black gums, which is one way to help anglers tell them apart from large silver (coho) salmon, which have grayish gums. The meat will typically be a pale pink. A king close to spawning will lose its silvery color and turn maroon to olive brown.
Silver (coho) salmon
Silvers are not as plentiful as reds, but generally arrive in more numbers than king salmon. This is one of the least understood species, biologically, because it is a tough one to measure. Rather than arriving in a big wave like other salmon, silvers trickle in at the tail end of summer and can be caught in Alaska even as ice shelves are creeping out from frozen riverbanks. This spirited fish is prized by anglers for putting on a spectacular fight when hooked, sometimes rocketing out of the water and skipping along on its tail.
Adults can weigh 8 to 12 pounds and be 24 to 30 inches long. Silvers are well-named. Their sides are bright silver with small black spots on the back and on the upper lobe of the tail fin. Their backs are blue-black. Anglers can tell them from king salmon by the lack of black spots on the lower lobe of the tail and by the whitish or gray gums. (Kings have black gums.) When spawning, their heads turn greenish-black and their bodies fade to dark brown or maroon.
Red (sockeye) salmon
Reds are one of the most prolific salmon species, swarming northern Pacific waters by the millions. The commercial fishery in Alaska's Bristol Bay alone, accounts for 10 million to 30 million reds. In prehistoric times, these plentiful fish were harvested as a primary food source up and down the Pacific Coast. Reds are considerably smaller than kings, but are a lot of fun to catch and prized for their excellent flavor.
A sockeye can weigh as little as 4 pounds after spending one to four years at sea, but most will weigh in the 6-12 pound range. Some can push the 15 pound barrier, although the world record weighs 15 pounds, 3 ounces. The length varies according to weight but most will fall into the 18-20 inch range.
Sockeyes don't have large black spots on their backs, dorsal and tail fins. They are dark blue-black with sides so silvery they flash like chrome on a sunny day. A spawning red salmon will develop a dark green head and fins, while their bodies will turn brick red or scarlet. Breeding males can have a humped back and elongated, hooked jaws filled with sharp teeth.
The meat is a bright orange-red and very firm, making the fish excellent grilled, canned, baked or dried with smoke.
Pink (humpy) salmon
Perhaps one of the most unfairly maligned of the salmon species is the pink, also known as the humpbacked salmon, or humpy. It gets the latter name because of the pronounced ridge that forms on the backs of males of the species before spawning.
Many salmon aficionados shun the lowly pink because these fish are smaller, and the meat can turn mealy if not stored promptly and properly. Pinks also arrive in abundance (Alaska's commercial fishermen can haul in 50 million to 75 million of these fish each summer), but humpies fight vigorously and are easy to hook.
Pinks are the smallest salmon in North America. They weigh 3 to 4 pounds and have an average length of 20 to 25 inches. They can be a bright steely blue on top and silvery on the sides with many large black spots on the back and entire tail fin. The scales are very small and the flesh is pink. As they move upstream and closer to their spawning beds, they can turn dull gray on their backs and creamy white on their bellies.
Chum (dog, keta calico) salmon
Chums range the farthest of the Pacific salmon species. They can be found from the Sacramento River in California to the island of Kyushu in the Sea of Japan. These fish typically aren't the mainstay of sportfishermen, but they are large, and their firm, pink meat is delicious smoked.
These fish are a staple in Alaska villages, where they are smoked and stored for winter food. Some Interior Alaska dog mushers feed these fish, dried, to their dog teams, which is why they are sometimes called dog salmon.
Chum can weigh as little as 4 pounds to as much as 30 pounds, but they usually range from 7 to 18 pounds. A fresh chum salmon will be metallic greenish-blue or gray on its back with fine black speckles. Its sides might be yellowish silver in a distinctive mottled pattern that looks a little like camo. As they reach spawning age, that camo pattern intensifies, with olive green and maroon backs and dull red or purple vertical bars on the sides (hence the "calico" nickname).
Source: Alaska Department of Fish and Game.