Why Do Kokanee Salmon Turn Red?

Salmon alter their color to entice a spawning partner. To get back to their home stream, lay eggs, and dig their nest, Pacific salmon expend all of their energy. When they get back to freshwater, the majority of them stop eating, and they run out of energy before they can spawn. They either decay after they pass away, releasing nutrients into the stream, or other animals consume them (but people don’t). Atlantic salmon, in contrast to Pacific salmon, do not perish after spawning, allowing adults to continue the spawning cycle for a number of years.

During the spawning season, a Kokanee salmon travels upstream along the Strawberry River in the U.S. state of Utah. From the end of August until October, the salmon run occurs. /AP Picture

In the American state of Utah, wildlife technicians catch Kokanee salmon in a trap and collect their eggs and milt during spawning season.

At a fish trap along the Strawberry River, some 32 kilometers southeast of Heber City, Utah, on September 18, a fish’s change from a silver color to brilliant red was on show.

Sockeye salmon species with no access to the sea, the kokanee salmon (Oncorhynchus nerka). They are often smaller than their ocean migrant brothers and spend their entire lives in freshwater.

When living in the ocean, sockeye are silver in color. Their heads change green and their bodies turn red when they return to the spawning grounds. Despite not migrating to the sea, Kokanee salmon are still silver before spawning.

The salmon start to absorb their scales during the spawning season. Therefore, the carotenoid colours in their skin are apparent. It is believed that the pigments facilitate the fish’s uptake of oxygen from the water.

The fish eggs and milt, or sperm, are transferred to a fish hatchery, according to Faith Heaton Jolley, a spokeswoman for the Utah Division of Wildlife Resources. Fish reared in hatcheries are sent to lakes all around the state once they are large enough.

According to Jolley, compared to the wild salmon’s likelihood of five to ten percent, hatchery-raised salmon had an 80 to 90 percent chance of maturing into adult fish.

Salmon, Kokanee

Recorded on October 7, 2008 | Download file | Play in new window | Duration: 4:00

Just east of Porcupine Reservoir, a little more than a week ago, I witnessed my first kokanee salmon running up Little Bear River. Within a mile of the reservoir, scientists found over 10,000 fish this year. That sets a new record. As they fought their way upstream, my friends and I were in awe of these writhing flashes of color. I was motivated to read about salmon for the remainder of the week. Here is what I discovered.

The genetic similarity between salmon and trout initially shocked me. They are all members of the Salmonidae family, along with grayling and whitefish, but salmon and trout share the greatest characteristics. The primary distinction between them is that salmon typically move from the freshwater environment where they were born to the ocean in search of more and better food. Then, in freshwater rivers and streams with fewer predators, they return to reproduce. Additionally, trout go through multiple spawning cycles while salmon only spawn once and then die, but this isn’t always the case.

For the majority of its life, the Pacific Sockeye salmon resembles a silvery rainbow trout. However, the male in particular experiences a spectacular change as it spawns. His body glows a bright crimson, his head turns green, and a bump appears on his back. His jaw then starts to hook, eventually resulting in a noticeable overbite. During breeding, there is a lot of competition for females, and his humpback and hooked jaw assist frighten rival male fish so he can fertilize more female eggs. And the opposite sex finds the color red to be quite alluring.

An evolutionary subgroup of the sockeye is the kokanee. Both of them migrate to a nursery lake to grow for a bit after they spawn in freshwater nurseries. Then the sockeye salmon migrates to the ocean while the kokanee remain in the lake. After a few years they both return to the freshwater streams to reproduce and die. The amusing thing is that a sockeye won’t turn red when it’s time to spawn if you keep him in a lake. This is due to the fact that red color is derived from carotenoid pigments, which are far more common in seafood. Therefore, why do kokanee turn the same shade of red as sockeye? The kokanee actually evolved the ability to synthesize carotenoid pigments with three times the effectiveness of sockeyes because of the extreme sexual predilection for red.

The kokanee has become a well-liked fish for reintroduction into western lakes and reservoirs because it flexibly designates a lake as its ocean. Bear Lake in Utah saw the first introduction of the kokanee for sport fishing in 1922. These days, you can observe them spawning in the Little Bear River, which emerges from Porcupine Reservoir, Sheep Creek, which is close to Flaming Gorge Reservoir, and Strawberry Reservoir’s tributary streams.

Kokanees are still spawning, and if you act quickly, you can catch the last of them. Their bright red bodies are an aquatic reaction to the flaming Utah maple on the nearby hillsides.

Regarding their comments on this article, we would especially like to thank Charles Hawkins (Watershed Sciences, College of Natural Resources, Utah State University), Phaedra Budy (Utah Cooperative Fish and Wildlife Research Unit, College of Natural Resources, Utah State University), and Bret Roper (US Forest Service, Fish & Aquatic Ecology Unit, Logan, UT).

Identification, development, and life cycle[edit]

Although the size of kokanee varies depending on numerous factors and is frequently lake-specific, in typical populations the kokanee grows to an average size of 23-30 centimeters (9-12 in) and weighs on average 0.45 kilograms (1 lb). In water bodies with better circumstances, it can grow to a maximum size of 51 centimeters (20 in) and weigh between 1.4 and 2.3 kilos (3-5 lb). The biggest kokanee was 2.83 kg and was caught in Washington State (6.25 lb). In open water where the thermocline is around 10 degrees Celsius, adult kokanee can be found (50 degF). They could have between 29 and 40 gill rakers. Because there is less food available to them because they spend their entire lives in freshwater, freshwater fish are frequently smaller than their marine sockeye counterparts. The most important morphological difference between kokanee and sockeye salmon is size, though gill raker count might vary from sockeye salmon. Plankton serves as this fish’s primary food source. “With the exception of chum salmon, kokanee are the only salmon and trout that lack definite dark patches on their backs and tail fins. Kokanee have blue backs and silver sides. They also have larger eyes, deeper forked tails, and finer scales than other trout “.

Kokanees generally follow a similar life cycle to other salmon. They move down to a lake, where they will spend the most of their adult lives, after being born in a stream. Kokanee often spend four years in a lake before returning to their breeding grounds where they spawn and eventually perish. But population longevity can change by 2 to 7 years. Kokanees can spawn at various times of the year known as runs. Kokanee runs are connected to individual populations and happen in lakes from August to February. In April, some kokanee were observed spawning. A redd is the name of the nest built by the female kokanee. Depending on the amount of food available, she will lay about 1,000 eggs. Within 110 days, the eggs hatch, and the young swim to the lake.

The males undergo a brilliant red color change during spawning and acquire a humped back and an extended jaw akin to the male sockeye salmon. During the breeding season, which coincides with the sockeye salmon spawning season, females also take on a dark red tint.

During the summer, competition with introduced lake trout may cause kokanee populations to fall. Since they are predators, lake trout will consume young kokanee. Kokanee populations in Lake Chelan, Washington, declined by 88 percent, with lake trout predation being responsible for 83 percent of that loss. The kokanee is in danger in some locations because to other reasons such pollution, habitat loss, and rising global temperatures.

Where to get kokanee salmon in Utah in fall that are brilliant red

In Salt Lake City Driving to see the leaves change color is a common pastime for many locals in Utah during the autumn, when the state’s landscape is filled with a variety of stunning hues. Kokanee salmon also turn a magnificent shade of red in the fall, so it’s not just trees that do.

Kokanee salmon, which are a silvery color most of the year, become vivid red in September and October before migrating up rivers and streams to breed. The fish are simple to recognize in the waters where they deposit their eggs thanks to their bright red hue. In addition, the males get hooked jaws, enlarged teeth, and humped backs during this spawning change.

Although the fish are exciting to view, be aware that from September 10 to November 30—during the spawning season—you are not permitted to keep any kokanee salmon you have captured anywhere in Utah. Wading into the water, letting their dogs chase the fish, or attempting to pick up the fish are all prohibited activities that could disturb the spawning fish.

The Utah Division of Wildlife Resources will not be hosting any public viewing activities this year because to worries about COVID-19. Nevertheless, from September to the beginning of October, you can still go observe the spawning kokanee salmon on your own. If at all feasible, go to these places during the week as the weekends might be packed. Make careful you adhere to social distance guidelines and have fun responsibly.

The kokes become red when, when?

We wanted to buy some red kokanee because my wife and I are organizing a vacation to the gorge. I am aware that they aren’t as delicious to eat now, but we still want to give it a go. Do the kokes start moving toward sheep creek at the moment the kokes turn around there in the gorge? We would appreciate hearing your opinions.

The Kokes typically begin changing LATE in July. It would be the first or second week of August if I only wanted to try for a full-blown red one. Regarding the Kokes’ migration, it has only recently started as they are beginning to leave their spring locations.

Kokanee salmon are always red, right?

The kokanee salmon is a topic of discussion among anglers and fisheries biologists. This fish resembles a sockeye salmon in most respects. Kokanee salmon are only different in that they live their entire lives on land, confined to vast lakes and reservoirs.

Of course, sockeye salmon are famous for being born in freshwater before migrating to the Pacific Ocean’s saltwater and returning to spawn in freshwater streams. The whole life cycle of a kokanee, on the other hand, is spent in freshwater lakes, streams, and reservoirs.

Their range is fairly constrained. Native to the United States, they can be found in states including Alaska, Idaho, Washington, and Oregon. They are also widely distributed in the Yukon Territory and British Columbia.

They have also been introduced in areas where they are not native, just like many other species of game fish. Kokanee populations are currently present in states including Wyoming, Utah, the Dakotas, New York, California, and Montana.

The two species have not yet been formally categorized as subspecies or separate species, despite considerable genetic evidence discovered by biologists to the contrary. For the majority of their lives, kokanee and sockeye salmon are silver. They are actually known to as silver trout or silver salmon in some regions. However, adult kokanee go through a drastic color shift to a brilliant red body and a black or green head when they are ready to spawn. Males also get a recognizable hump. Kokanee that are in the process of spawning use both deep water and streams for reproduction.

Because kokanee frequently spawn in extremely shallow water and the red hue makes them very easy to identify, they occasionally become prey for human poachers as well as large natural predators like bears and eagles during this vulnerable time.

The average weight limit for huge kokanee is six pounds. The IGFA world record fish was captured at Wallowa Lake, Oregon, in 2010, and it weighed 9 pounds, 10 ounces. Because this species dies after spawning, it doesn’t get very big. Even said, it’s noteworthy to note that some kokanees have grown larger and never reached the “red fish” stage of their existence.

For instance, in Lower Arrow Lake in British Columbia in 2017, an angler captured a fish that he mistook for a sizable rainbow trout. He delivered the rest of the corpse to scientists after realizing it might be a kokanee when he later went to cook it.

Later, they were able to positively identify the 12-pound fish. If the angler had known and not eaten the majority of it, it would have destroyed the previous world record.

According to experts, this kokanee was past its prime at seven years old and had likely missed its chance to breed, as they only live for four to seven years in the wild.