Among the many sought-after game species, salmon certainly rank high for their ability to get your heart beating like mad when they swallow a fly. The ensuing fight will be legendary, even on the best 11-weight money can buy.
As hard-fighting as they are strikingly colored, working the salmon run with a fly rod is the stuff of dreams.
Native to both northern coasts of the United States, these cold-water species have been introduced widely, even into freshwater environments like the Great Lakes.
And while many fish are nicknamed “salmon,” true salmon are members of the Salmonidae family and the genera Salmo and Oncorhynchus.
They share two traits that distinguish them from most other game fish.
The first is that they can adapt to a wide range of salinities, a trait biologists refer to as euryhalinity. Euryhaline species like salmon can osmoregulate, meaning that they can control how much water their bodies absorb or excrete, allowing them to rapidly move between fresh and saltwater environments without suffering any ill effects.
The second trait salmon share is that they are typically anadromous, spending their adult lives out in the sea before returning to freshwater streams to spawn. This creates excellent opportunities to troll for salmon in saltwater and target spawning salmon in freshwater streams on both coasts.
There are seven species of salmon, and each deserves a close look.
Table of Contents (clickable)
Atlantic salmon (Salmo salar)
Growing to as long as three feet, the Atlantic salmon is second only to the Chinook in size, but it can reach incredible weights, sometimes as high as 100 pounds or more.
Average Atlantic salmon will reach lengths ranging from 28 to 30 inches, at which point they’ll weigh between 8 and 12 pounds. Adults of this species will sport distinctive spots along the upper half of their body, as well as a darker green-gray dorsal side, especially on the head.
Atlantic salmon begin life in clear, cold streams, where they begin eating plankton and tiny invertebrates before moving up the food chain to consume insects and small fish.
Many stages mark the periods of the Atlantic salmon’s life cycle.
The first, when they remain in the gravel substrate of their breeding grounds and take their nutrients from their yolk sacs, is called the alevin stage.
A salmon alevin draws its nutrients from its yolk sac.
The second, the fry stage, finds them leaving their birthplace as free-swimmers and actively hunting for food. In the third, as they prepare to leave for the sea, they reach the parr stage, growing rapidly into the fourth stage prior to maturity, called the smolt stage.
Between March and June, Atlantic salmon smolt will move downstream, acclimatizing to the increased salinity through osmoregulation, and then eventually swim into the sea on an ebb tide.
This Atlantic salmon smolt is far from mature. But it’s starting to look like a salmon should.
In the ocean, their primary food source is capelin, a type of smelt. Herring, alewives, scombrids, sand lances, and small cod round out the Atlantic salmon’s menu, and they grow rapidly, reaching average sizes within one to four years.
Once they’ve grown sufficiently, they’ll enter what is typically the final stage of their life, the grilse stage. At this point, they’ll be driven by instinct to return to their native stream, cease feeding, and begin spawning.
Unlike the Pacific species, Atlantic salmon are iteroparous. This means that between 5% and 10% of their number survive the spawn and return to the sea to repeat the cycle again next year.
Another unique feature of the Atlantic salmon is that some populations are limited to freshwater environments such as the Great Lakes. These populations are referred to as potadromous, but their life cycle is the same as their more common saltwater kin, only that rather than moving to the salt once mature, they seek out the expansive freshwater biome of the Great Lakes before returning to their home streams to breed.
Any angler would be proud of this Great Lakes Atlantic salmon!
Chinook salmon (Oncorhynchus tshawytscha)
Chinook (also known as king salmon) are the giants of the salmon family, reaching average sizes of 24 to 36 inches and 10 to 50 pounds, but they may grow to as large as an amazing 58 inches and 130 pounds!
Their color varies widely, with blue-green, red, or purple crowning their dorsal side, fading to silver and then white on the ventral side. Dark spots adorn the upper sides and top of the Chinook salmon, and distinctively, they sport silver, spotted tail fins.
As they prepare for the spawn, however, they dramatically change their appearance, darkening to a coppery brown and losing their silver hue. The males will develop canine-like teeth and a downward-curving upper lip called a “kype.”
Chinook salmon tend to breed in deeper water than Atlantic salmon and other salmon species, and once reaching the smolt stage, most move downstream to tidal estuaries to continue to grow before heading out to sea. These are referred to by biologists as “ocean-type” Chinook.
But other smolts remain in freshwater environments for an entire year before making the transition to the sea. These Chinook are called “stream-type” salmon.
Once at sea, Chinook feed on fish like herring, as well as squid. In clean, healthy environments, Chinook salmon grow rapidly before returning to their native spawning grounds where they inevitably die post-spawn, providing a veritable feast for everything from bears to birds.
Chum salmon (Oncorhynchus keta)
Chum salmon are one of the smaller true salmon species, with average lengths and weights of just under 24 inches and 10 to 22 pounds. But larger examples have been caught, with the world-record specimen tipping the scales at 44.1 inches and 35 pounds!
While at sea, chum salmon have a mottled blue or purple coloration that marks them apart from other salmon species, but as they approach the spawn, they darken to olive green or shades of brown, taking on distinctive purple blotches on their sides.
And like Chinook salmon, the males develop pronounced canine teeth as well as the distinctive kype.
Chum salmon start life like all salmon, in streams and tributaries, but once they're free-swimming fry, they head for the ocean, where they mature through the stages of parr and smolt, reaching maturity in 3 to 5 years.
They then return to their breeding ground to spawn and die.
Coho salmon (Oncorhynchus kisutch)
Coho salmon grow to as long as 28 inches, at which point they can weigh as much as 36 pounds.
Easily identifiable by their almost metallic silver sides and dark blue backs, Coho salmon undergo a dramatic color change just prior to spawning.
As they begin their long journey upstream to breed and die, they’ll lose the silver and blue they’ve worn for most of their lives, turning bright pinkish-red. Both sexes develop kypes, with their heads taking on an inky color.
You won’t mistake a spawning Coho for anything else!
During the alien stage, like all salmon, they stay put in the rocks and gravel of their stream bed. But upon reaching the fry stage, they’ll remain in their home stream or river for one or two years, growing through to the smolt stage.
In late March through July, many Coho smolt will head to the ocean, but some migrate to estuarial regions, stop short of the sea, and return to freshwater for the winter.
The oceanic portion of the Coho salmon’s life can last from one to three years before they instinctively return to their birthplaces to spawn.
Masu salmon (Oncorhynchus masou)
Masu salmon are more common in Japan than the West Coast of America. There, they’re commonly referred to as “trout” - the literal translation of “masu” - or cherry trout, given their distinctive coloration.
Average sizes for Masu salmon are in the neighborhood of 20 inches, with fish of this size typically weighing about 5 pounds. They can grow larger than this in ideal conditions, however, and on the Russian coast opposite Japan, examples as long as 28 inches weighing an incredible 20 pounds have been caught!
In their oceanic phase, Masu salmon are recognizable by their blue or green backs, spotted sides, and pale bellies. But as they prepare to spawn, like many other salmon, they undergo a shift in color and pattern, gaining vertical stripes of bright pink on both sides.
Masu begin life in clear, cold, rocky streams and rivers, where they may spend several years maturing through the typical stages of a salmon’s life.
Once they migrate to the ocean, they feed primarily on crustaceans, skipping the diet of fish and squid common to their close relatives. They remain in the salt for some time, no less than three years but sometimes as long as seven, before returning to their home waters to breed.
Like Atlantic salmon, some fish survive the spawn - typically dwarf males - who will breed again next year and die soon after.
Pink salmon (Oncorhynchus gorbuscha)
The smallest and most common true salmon, the pink salmon sports a gray back that’s spotted down its sides. A pink blush can run down the midline of these salmon, giving them their common English name.
Averaging about 5 pounds, they can grow larger, with the world record being a 30-inch, 15-pound monster!
And though the pink salmon is native to the Pacific, breeding populations have been established in the Great Lakes, where they live potadromous lives, breeding in streams and tributaries before migrating to the waters of the Great Lakes to mature.
When pink salmon are sexually mature, being instinctively drawn to the streams and rivers of their birth, the males undergo a morphological change that dwarfs the color changes of other closely-related species.
They’ll develop a pronounced hump, from which their Latin name is drawn through the Russian “humpy,” or gorbuscha.
At this point, the males will lose most of the bright colors and spots, turning a deep lime green or gray with only a hint of the pink line remaining. They also develop a skype and fierce-looking teeth.
Breeding occurs in two cycles, with pink salmon maturing on a strict time-table that keeps successive year’s fish separate. Thus, this year’s salmon, reaching maturity, will only breed with others born in the same year, with that same two-year cycle continuing forward indefinitely.
Sockeye salmon (Oncorhynchus nerka)
Sockeye salmon are one of the larger species of the genus Oncorhynchus.
Growing as large as two feet, nine inches and weighing as much as 15 pounds, these are an exciting fish to fight on fly tackle.
While most sockeye live anadromous lives, migrating from fresh- to saltwater and back to fresh again to finish their days, some populations are entirely potadromous and typically much smaller than their oceanic kin.
In their lives in the ocean, they sport dark blue backs fading to silver sides and bellies. Unique feeding behavior, in which sockeye move vertically through the water column in search of prey, as well as diet of zooplankton and shrimp, mark the sockeye as distinctive.
Whether oceanic or lake-bound, as they reach spawning age, they transform their appearance, rivaling the pink salmon in the degree of difference.
Sockeye trade blue and silver or a striking pink or red, and their heads swap from blue-black to olive green. Like the pink salmon, males develop an enormous hump as well as a skype and pronounced canines.