A beginner angler’s introduction to the sport of fly fishing probably involved catching a rainbow trout at some point. These fish are everywhere- you can find them in the mountain streams of the Appalachians to the cold waters on the Pacific coast of Russia. They are found in every continent in fact, and have been introduced to areas where they aren’t native to.
So common are the rainbow trout that their existence in some places overlap with a very close relative of theirs- the cutthroat trout. The two fish look fairly similar that some anglers find it difficult to tell them apart. Further complicating the issue is that these fish are known to interbreed and produce offspring that look like both parents.
As an angler, it’s important to know what kind of fish you’re looking at, especially one that is as common as the rainbow and the cutthroat trout.
Rainbow Trout vs Cutthroat Appearance: What Do They Look Like
It’s important to note that the rainbow and cutthroat trout are two very distinct and very different species of trout, even though they come from the same family and genus of fish, Salmonidae oncorhynchus. The two species can be found in different locations, breed during different times of the year (spring for the rainbow trout, and autumn/winter for cutthroat), and have distinctive visual markings on their bodies that set them apart from the other.
Both have numerous recognized subspecies that also have their own unique visual identifiers. Despite the vast number of subspecies that they have, these all display certain common markings that identify them as belonging to their respective trout family. Here’s how you can differentiate a rainbow trout from a cutthroat and vice versa.
Rainbow Trout vs Cutthroat Sizes
Adult rainbow trout that live in river environments can weigh anywhere between one to five pounds while those that live in lakes- especially steelheads- can reach up to an average of 20 pounds. For the most part, habitat and the size of the body of water that the trout is living in will ultimately decide its size. In the Appalachians, a half pound rainbow trout is already considered a good catch. While in Alaska, catching trout that weigh 10 pounds or more is nothing new.
The same goes true for cutthroat trout. Their sizes are heavily dependent on habitat and food-availability. Cutthroat that live near coastal areas can average around two to five pounds. Those that live in lakes reach very large sizes upon maturity, sometimes up to 12 to 17 pounds especially if their growing conditions are ideal. Stream-dwelling cutthroat trout are the smallest, only growing to weigh around 90 grams and even less when they reach their adult stage.
Rainbow Trout vs Cutthroat Differences: How to Tell Them Apart
How to Identify a Rainbow Trout
In taxonomy, rainbow trout are classified under the scientific name Oncorhynchus mykiss. They are widely farmed in some lakes and rivers both as table fish and as a gamefish. It is considered to be among the most popular and most iconic freshwater species in fly fishing in North America.
There’s another distinct form of rainbow trout called steelhead that are considered as anadromous. When you say that a particular fish is anadromous, it means that they live in both salt and fresh water at different points in their lives. The steelhead rainbow trout initially hatch in freshwater, then once fully grown, swim to the ocean and live in saltwater for a few years. Once they reach reproductive maturity and are ready to hatch eggs, they move back to the nearest body of freshwater again.
As for the coloration, this varies widely among rainbow trout populations per habitat, age, spawning condition, and subspecies. Though generally rainbow trout have a multi-hued coloration on their bodies- which can be blue, green, or yellowish- with some silvery-white shading on the underside of their bellies. This is why people call them as “rainbow” trout in the first place. They also have a very noticeable pink or reddish stripe that runs the length of their bodies, as well as black spots that along their sides and backs. Steelheads and lake-dwelling rainbow trout usually have a more silverish color to them, with their red stripes a very light hue (almost pink in color). There are also species of rainbow trout call
The caudal fin (i.e. the fin that is located on the fish’s tail) is very angular and squarish in shape, with a mild fork in it. Young juvenile rainbow trout often have dark vertical bars (also called as parr marks) on their bodies, which would eventially disappear once they reach adulthood.
How to Identify a Cutthroat Trout
Cutthroat trout have the scientific name of Oncorhynchus clarkii, so named because of the fact that the species was first examined and described during the Lewis and Clark Expedition in the early 19th century. The name was given to honor William Clark, who was the co-leader of the expedition.
Cutthroat trout also have multi-hued coloration, with specific colors and hues varying according to subspecies, habitat, and other factors. Their colors can range from gold to gray, as well as green on their backs. These fish earned their special name of “Cutthroat” because of the presence of distinctive pinkish or reddish marks on the underside of their lower jaws and the lower folds of their gill plates, thus making it look like as if their throats are cut. This name was first introduced by nature writer Charles Hallock in an article he wrote for The American Angler in 1884.
Rainbow Trout vs Cutthroat Trout Habitats
Rainbow trout are native to a lot of streams, rivers, and lakes on the west coast of North America that drain into the Pacific. This can extend from Alaska in the north to Mexico in the south. These fish are also found on the Pacific coast of Russia, on the Kamchatka Peninsula (which is the part of Russia that is closest to Alaska).
However, rainbow trout have been artificially bred and farmed in places outside of their native habitats since the late 19th century. Rivers and lakes across the USA and Canada were originally stocked with rainbow trout by hiking up buckets of them through the mountains and dumping them onto the water- this was done specifically to attract anglers and other tourists. Up to this very day, this practice continues to help replenish the rainbow trout population that have died off during the winter.
Barring Antarctica (a place too cold for these fish to survive in), rainbow trout can now be found in every continent in the world.
Cutthroat trout populations aren’t as widespread as that of the rainbow trout’s. These fish are native to the western part of North America, with their populations highly concentrated in lower Southeast Alaska up to Prince William Sound. These fish are the most common trout species in this region. Although cutthroat trout have also been introduced to areas where they were not native to, these places are just usually confined to the United States. Some of the places where cutthroat trout have been artificially introduced to include the lakes in the Yellowstone National Park (where most of the lakes were fishless before the trout was introduced to them), tributaries in Lake Michigan, and the high mountain lakes in the White Mountains of northeastern Arizona.
Rainbow Trout vs Cutthroat Trout Fishing Techniques and Baits
Anglers love to fish for rainbow trout- it’s probably one of the easiest fish to catch due to the fact that it can be found almost everywhere.
For rainbow trout, anywhere where there’s clean water whose temperature are consistently above freezing and below 67 degrees Fahrenheit are ideal. It’s important to know that these trout are very sensitive to water conditions and won’t feed if the conditions are not ideal for them.
You can fish for rainbow trout all year round- but fishing in the spring and fall seasons will garner you more bites. And since rainbow trout are most active in the early morning and sunset, it’s best to fish for them during these times.
As for bait, rainbow trout will eat anything they can get their mouths on, so minnows, salmon eggs, flying and terrestrial insects, nightcrawlers are all on the menu.
Cutthroat trout are trickier to catch, for the sole reason that there’s not that many of them around. There are even some subspecies of cutthroat that you are absolutely not allowed to fish, since their populations have dwindled so much because of overfishing and mining pollution. It’s best to know what kind of cutthroat you’re allowed to fish before setting off on your fishing expedition.
Cutthroat, like the rainbow trout, eat almost anything, though they have a have a huge preference for aquatic nymphs and larvae. This kind of trout can also be caught all year long, though they’re mostly inactive during winter so it’s not recommended to fish for them during this season. April to October are the months that offer the best fishing conditions for cutthroat trout.
Rainbow Trout vs Cutthroat Trout Meat – Taste, Flavor, Color
Rainbow trout meat has a color that ranges from white to pink and orange. When cooked, its meat has a very mild, and an almost nut-like flavor or aftertaste. The meat also pales in color when it’s cooked, and turns very flaky and soft.
Cutthroat trout has a darker, pink-colored flesh that almost looks similar to salmon. These fish have a more pungent taste to them which some people like (and which some people are turned off by). Cutthroat trout is usually served by filleting them first and frying them in butter or olive oil.
Both kinds of trout are low in calories, and high in protein, omega-3, potassium, selenium, vitamin D, and vitamin B12.