Tag Archives: Coho Salmon

Which Salmon Is It?

Over the past several weeks, I’ve been writing about Pacific salmon, so this week, I want to pause a minute and review. In their marine phase, the five species of Pacific salmon are hard to tell apart. Their life cycles are similar, and sometimes all five species spawn in the same river/lake system. What are their differences, and how do you tell one species from another?

Perhaps you are thinking, why should I care if I can differentiate between salmon species? Let’s pretend you are fishing in Alaska on a river where all five Pacific salmon species are present. It is legal to keep pink salmon, chums, and cohos, but you must release sockeyes and kings. You catch a beautiful, silvery salmon. You know right away it hasn’t been in fresh water long enough for its color and body shape to change. You also know if it is still silver in color, its flesh will be firm, and it will be good to eat. Is this one of the species you can keep, or must you release this fish?

The size of the fish is a clue, but often, different year classes of a species return to the same river, so size is not definitive. Does the fish have spots, and if so, where and how big? Spots are more visible when a salmon gains its spawning coloration, but if you look closely, the spots are visible in the silvery marine phase. Pink salmon have large, oval spots on the back and both lobes of the tail. Cohos have small black spots on the back and the upper lobe of the tail. Kings have spots on the back and both lobes of the tail. Sockeyes and chums have no spots on their backs or tails.

While you are looking at the tail, do you see any silver streaks? Cohos and kings have silver streaks radiating along the rays of the tail. Chums also have silver streaks but only on half the tail.

The mouth is another distinguishing characteristic. King salmon have a black mouth with a black gum line and a black tongue. Pinks also have a black gum line, but they have a white mouth. The other three species all have white mouths and white gum lines.

A chum salmon has a white tip on the anal fin, an important characteristic to note when trying to differentiate a chum from a sockeye.

Other distinguishing characteristics you can use include the size of the eye, scale size, and the shape of the tail, but none of these are easy to employ unless you are comparing one salmon to another.

Take a look at the salmon you caught. It weighs about four pounds and has spots on the back and both lobes of the tail. You think you see silver streaks in the tail, but you’re not certain, so you check the mouth and note a black gum line and a black mouth. You are allowed to keep the fish if it is a pink,  chum, or silver salmon, but you must release it if it is sockeye or king. Will you be able to grill this salmon for dinner, or should you carefully release it back into the stream?

The size of the fish, and the spots on the back and both lobes of the tail may lead you to jump to the conclusion you caught a pink salmon, and you can keep it. Only pinks and kings have spots on both lobes of the tail, so you can quickly rule out the other three species. The silver streaks in the tail may be hard to see, so you wisely check the mouth. Both pinks and kings have black gum lines, but only king salmon have a black mouth, including a black tongue. Take a closer look at the fish. Are the spots small or are they large and oval? If you said small, you have your answer. You caught a small, probably a mature 3-year-old king salmon, and you must release it.  

It takes practice to identify a silvery Pacific salmon in its marine phase. Commercial fishermen can quickly differentiate one species from another, but if you only occasionally fish for salmon, one silver salmon looks much like the next. If you can’t identify the salmon you caught, you must release it, so if you plan to go salmon fishing in Alaska without a guide, you should do your homework first.

Next week, I’ll write about some of the questions we are commonly asked about salmon, and I will do my best to answer them.

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I am excited to announce the webinar I told you about last week explaining how I became an Alaska wilderness mystery writer and where I get some of my ideas for my novels, has now been released. To see the webinar, follow this link: http://bit.ly/2pcCOo6. I used many of Mike’s photos and my friend, Ryan Augustine’s photos and videos in the webinar, so I think you will enjoy it. Please share the webinar link with your friends and family. If you stay until the end, you can get a free e-book of one of my novels. The purpose of the webinar is to introduce myself and my books to a wider audience, so the more you share this link, the happier I will be! Thank you!

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Commercial and Sport Fishing for Coho (Silver) Salmon

Last week, I wrote about the life cycle of a coho salmon, and I mentioned cohos are the most aggressive species of Pacific Salmon. Their aggressive nature makes them a favorite target for anglers. Cohos can be caught in the ocean and their spawning streams. They hit a lure or a fly hard and are tenacious fighters, often leaping out of the water and running fast both away and toward the fisherman. Coho salmon are also an important commercial species, but there are not nearly as many cohos as there are pink, chum, or red salmon, so cohos are not as economically valuable to commercial fishermen as these other Pacific Salmon species. In this post, I will cover both the commercial and sport fisheries for coho salmon, and I will discuss the current status, threats, and trends of cohos in their native range.

Commercial Fishery for Cohos in Alaska

 In most of the state, commercial fishermen catch coho salmon together with other salmon species by purse seining and gill netting. In Southeast Alaska, though, the majority of coho salmon are caught by the commercial troll fishery.[9] In 2017, commercial salmon fishermen in Alaska harvested nearly 225 million Pacific Salmon. Five million coho accounted for 2% of the harvest, but due to their large size and a price of nearly $1.20 per pound, the commercial coho catch was worth 38 million dollars, or 6% of the total salmon harvest value.[10]

Sport Fishery for Cohos in Alaska

The coho salmon is one of the most sought-after game fish in Alaska, and since the decline in king salmon numbers over the past few years, the sport fishery for cohos has become even more popular. Cohos are targeted by anglers in salt and fresh water from July through September in Alaska, and sport anglers catch nearly 1.5 million cohos every year in the state.[9]

In salt water, cohos are mostly caught by trolling or mooching. Herring is a popular bait, and any jig that looks like a small fish works well. Cohos are not particular about the bait or the jig as long as the angler keeps the jig active. The biggest challenge of catching cohos in the ocean is finding them. They may be at any depth from the surface to eighty feet or deeper.

Cohos are more finicky once they enter their spawning stream when their bodies change shape and color, and they stop eating. They will still aggressively hit a lure or a fly even after they gain their spawning colors, but they often become shy of lures, especially on a sunny day. Popular freshwater lures for spin fishing include Pixee spoons, golf tees, and spinners.

Status and Threats for Cohos

 Many coho salmon populations in California and the Pacific Northwest are threatened or endangered, but coho populations in Alaska are healthy.[9] In the southern part of their range on the west coast of the United States, humans have altered much of the coho’s habitat by urban development, constructing dams, diverting streams and rivers for agriculture, recreation, mining, logging, and other human-related activities. Studies show that in most western states, 80 to 90 percent of the historic riparian habitat has been destroyed, and 53 percent of the wetlands in the lower 48 have been eliminated. California has lost 91% of its wetland habitat, and wetlands in Oregon and Washington have been diminished by one third.[9] How can coho salmon with their complex lifecycle in fresh and salt water possibly thrive when much of the habitat they need to survive is gone?

Throughout their range, including Alaska, coho salmon will likely be impacted by warming ocean temperatures.

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I am very excited to announce my new novel, The Fisherman’s Daughter, will be available at online booksellers on November 1st. I am nervous but thrilled as I await its release. I want to again thank all of you who pre-ordered my novel.

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Coho or Silver Salmon (Oncorhynchus kisutch)

Coho salmon, often called silver salmon due to their beautiful bright chrome color, are the most aggressive of the Pacific Salmon species. There aren’t as many cohos as there are pink salmon, chum salmon, or sockeye salmon, but coho salmon manage to spawn in tributaries and small headwaters inaccessible to other salmon species. A Coho can leap vertically six feet (1.8 m) to overcome obstacles such as rapids or waterfalls on its return journey to its spawning stream, and cohos usually migrate to their spawning streams later than other salmon species at a time when fall floods allow them to access areas not available during lower water levels.  Even young cohos are aggressive, and they often eat the young of other salmon species. This aggressive nature of coho salmon makes them excellent fighters on a rod and reel and an important species for the sportfishing industry in Alaska.

Range

The natural range of coho salmon is from Monterey Bay, California north to Point Hope, Alaska, west across the Bering Sea to the Anadyr River in Siberia, and south along the coast of Asia to Japan. Cohos have been introduced to the Great Lakes and other lakes in the Continental U.S. Cohos spawn in ponds, lakes, and pools within streams and rivers.

Description

Coho adults usually weigh between 8 and 12 lbs. (3.6-5.4 kg) and range from 24 to 30 inches (61-72 cm) in length, but fish weighing up to 31 lbs. (14.1 kg) have been caught. During their marine phase, adults are bright silver and have small, black dots on the back and the upper lobe of the tail fin. In their marine phase, cohos look very similar to king (Chinook) salmon, but king salmon have spots on both lobes of the tail, while cohos only have spots on the upper lobe. Another way to distinguish the two species is cohos have white gums, while king salmon have black gums.

When cohos return to freshwater to spawn, males turn dark to bright green on the head and back, bright red on the sides, and dark on the belly. Breeding females are not as brightly colored as males. Spawning males develop a hooked jaw called a kype.

Life Cycle

In Alaska, coho salmon return to their spawning streams from July to November, usually during periods of heavy rain and high runoff. On Kodiak, most cohos return from late August through October. A female coho selects a suitable spot and then begins to dig a nest, or redd. She turns on her side and gives several powerful flips of her tail to remove silt and other debris and then continues to dig for two to five minutes until she has a shallow nest. While she is digging her nest, she aggressively drives away other females. Meanwhile, a male coho stays near the female while she digs the nest, occasionally swimming close to her. He may also stop beside her and quiver, swim over her and touch her dorsal fin, or nudge her side with his snout. When the female has finished excavating the nest, she drops into the deepest part of the depression, and the male immediately joins her. The two fish remain side by side in the nest while they open their mouths, quiver, and release eggs and sperm. The female then moves upstream and begins digging a new nest, covering the eggs in the first nest with the gravel she dislodges from the second nest. Nest digging and spawning may continue at intervals over the next several days, until the female deposits all her eggs. The male might then leave and seek another female, but the female will continue the digging process until she grows weak and dies.

A female coho lays between 2,400 and 4,500 eggs. The eggs develop over the winter and hatch in the early spring. The alevin, with the yolk sac attached, remains in the gravel until May or June before emerging. Young silver salmon fry usually spend between one and three winters in fresh water, but some spend as many as five years in a lake before migrating to the ocean. Young silver salmon in Karluk Lake on Kodiak Island often stay two, three, or even four years in fresh water before migrating to sea. The length of time spent at sea also varies for coho salmon. Some males, called jacks, mature and return after only six months at sea, but most cohos remain in the ocean for 18 months to three years and return as full-size adults.

Prey and Predators

Cohos are aggressive feeders. In freshwater, they eat a wide range of aquatic insects and plankton. They also eat salmon eggs, and as they grow, the fry also consume smaller fry. In the ocean, cohos eat herring, sand lance, other fish, and squid.

Young coho are eaten by birds, larger fish, and a variety of other predators. Killer whales, sharks, sea lions, seals, bears, humans, and other land mammals prey on adult cohos.

Next week, I will cover commercial and sport fisheries for cohos as well as threats to coho salmon populations.

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Announcements

The publication date has changed for my novel, The Fisherman’s Daughter. Now, both the e-book and print versions of the novel will be released on November 1st. You can still pre-order the e-book, and it will be delivered to your device as soon as it is released. If you pre-ordered my novel, thank you!

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