Tag Archives: Pacific Salmon

Sockeye (Red) Salmon (Oncorhynchus nerka)

Sockeye salmon also called red salmon and sometimes blueback salmon, are larger than pink salmon but average smaller in size than other Pacific Salmon species. Sockeyes measure between 18 and 31 inches (45.7-78.7 cm) in length and weigh between 4 to 15 pounds (1.8-6.8 kg). In their marine phase, sockeyes have iridescent silver sides, a white belly, and a metallic green-blue back. Due to this marine coloration, sockeyes are sometimes called blueback salmon. While they can have fine, black speckles on their backs, they lack the large spots found on other species of Pacific Salmon. The flesh of a sockeye in the marine phase is bright orange and firm. This beautiful, firm flesh with its rich flavor makes sockeyes highly prized and a culinary favorite.

When sockeyes return to their natal streams to spawn, their bodies turn bright red, and their heads become green. They are called red salmon because of this spawning coloration. In addition to changing color when they return to spawn, males develop a humped back, and hooked jaws called a kype. Breeding females are paler in color than males.

Unlike pinks, chums, and cohos that can spawn close to the mouths of small streams, sockeye salmon usually spawn in large, complex river/lake systems. Most sockeyes spawn either in streams connected to lakes or along the lakeshore in areas of upwelling. Because a sockeye requires unimpeded access to a lake to complete its life cycle, it is susceptible to habitat manipulation or degradation. Not only man but also beavers can alter a river system by building dams, effectively blocking a river or stream and denying salmon access to the lake.

The natural range for sockeyes is from the Klamath River in California and Oregon north to Point Hope in Alaska. In the western Pacific, sockeyes range from the Anadyr River in Siberia south to Hokkaido, Japan. Sockeyes are most numerous in the Fraser River system in British Columbia and the Bristol Bay system, including the Kvichak, Naknek, Ugashik, Egegik, and Nushagak rivers. Some populations of sockeyes do not migrate to the ocean but spend their entire lives in freshwater. These landlocked salmon are called kokanee salmon. Kokanees are found from Siberia to Japan on the Asian side of the Pacific and In North America from the Kenai Peninsula to the Deschutes River in Oregon. Kokanees have been widely introduced to lakes in the U.S., including the Great Lakes.

In Alaska, sockeye salmon return from the ocean to spawn from July to October. Like other Pacific Salmon species, sockeyes spawn in the streams where they were born. Some sockeyes spawn in streams not connected to lakes and others spawn near the lakeshore, but most spawn in streams attached to a lake. A female digs a nest in the stream bottom by giving several, powerful strokes of her tail. Once she finishes digging the nest, she rests while a dominant male courts her by nudging her side with his snout and then coming to rest beside her and quivering. The female then drops into the nest, and the male follows, stopping beside her. Both fish arch their bodies, open their mouths and quiver, releasing their eggs and sperm. Other males may also enter the nest and release sperm. The female will continue to dig nests until she has deposited all her eggs. She usually digs three to five nests over the course of three to five days, and she may breed with several dominant males. A female deposits between 500 to 1,000 eggs in a nest and lays a total of 2,500 to 4,300 eggs. A male sockeye may breed with several females, and both male and female sockeyes die within a few weeks after spawning.

Sockeye eggs hatch in the winter, and the young alevins remain in the gravel, gaining nutrition from their yolk sacs until spring when they emerge into the stream. At this stage of their lives, the young sockeyes are called fry and have dark, short, oval parr marks on their sides. Fry move out of the stream and into the lake where they spend one to three years in fresh water, feeding on zooplankton and small crustaceans. As they prepare to leave the lake, sockeyes lose their parr marks and turn silvery. They are now called smolts. Smolts weight only a few ounces when they enter the ocean, but they begin to grow quickly, mostly feeding on plankton, insects, and small crustaceans. A sockeye’s beautiful orange flesh comes from eating plankton and krill in the ocean.

Sockeyes spend one to four years in the ocean where they travel nearly continuously, covering as many as 2300 miles (3700 km) in one year. As it begins the return trip to its spawning stream, a mature sockeye swims even faster, covering 28 to 35 miles (45-56 km) per day during its last two months at sea. Sockeyes are prey for nearly every animal they encounter that is bigger than they are, and they are a valuable species for commercial fishermen.

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Next week, I will cover the commercial and sport fishery for sockeyes as well as the status of sockeye populations and threats to their survival, including the controversial proposed Pebble Mine in Bristol Bay, Alaska.

I would love to hear your opinions and ideas about the Pebble Mine as well as about anything else related to salmon conservation or any of my other posts.

My novel, The Fisherman’s Daughter, is now available for sale at Amazon and other online booksellers, as well as on my page at www.authormasterminds.com

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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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Chum Salmon (Oncorhynchus keta)


Chum salmon (Oncorhynchus keta) are the most widely distributed Pacific Salmon species and can be found throughout Alaska. They range along the east and west coasts of the North Pacific Ocean, from the Mackenzie and Anderson Rivers in Canada to the Lena River in Russia.

Chums are often called dog salmon, but experts disagree about the origin of this nickname. Some believe chums are called dogs because, in the Arctic, Northwestern, and Interior parts of Alaska, chums were and still are traditionally dried and used as a winter food supply for both humans and dogs. Others argue they are called dog salmon because of the enlarged “canine” teeth the males develop during the spawning season.

Chum salmon are the second-largest Pacific Salmon species. Only Chinook (King Salmon) grow bigger. An average adult chum salmon weighs between 8 and 15 lbs. (3.6 to 6.8 kg), but they can grow as large as 45lbs. (20 kg). During their marine phase, chums are dark metallic blue on the back and silver on the sides and belly. Tiny dark specks may be present, but chums do not have large spots like those on Chinook, coho, and pink salmon. The tail of a chum salmon is highly forked, lacks spots, and has silver streaks along the fin rays.

When chums enter fresh water on the return to their spawning streams, males darken to what is often described as a calico pattern. They turn a dark olive brown and have red to purple, wavy, vertical stripes. They also develop hooked jaws called a kype lined with large, sharp teeth. Females turn brown and have a dark, thick, horizontal bar running along the lateral line. Females also develop a hooked jaw with large teeth, but the jaw is less pronounced than it is in males.

There are two, distinct races of chum salmon that spawn at different times. Summer chums spawn in early to mid-summer, and fall chums, as their name suggests, spawn later in the autumn. Chum salmon usually spawn at the mouth or in the lower sections of a stream or river, but in large river systems, they may travel as far as 2000 miles (3219 km) upriver to spawn.

When spawning, a female chum digs a nest in the gravel of the streambed. She then deposits her eggs in the nest while one or more males release sperm to fertilize the eggs. The female may dig more nests upstream from the first nest, depositing her eggs in the nests until her eggs are gone. A group of nests is called a redd, and a female guards her redd until she becomes weak and dies.

Chum salmon eggs hatch after three to four months. The alevin that emerges from the egg remains in the gravel, receiving nutrients from its yolk sac for 60 to 90 days. When it emerges, a chum salmon fry is dark greenish-brown on the back and iridescent green below the lateral line. It also has 8-12 vertical, spaced parr marks on the upper half of its body, not extending below the lateral line.

Fry begin migrating downstream to the ocean within a few days to a few weeks after emergence when they are only one to two inches long. Young chums spend several months near shore before traveling to the open ocean. They stay in the ocean three to four years where they grow to a size of 8 to 15 lbs. (3.6-6.8 kg) or larger. They grow the fastest during their last year in the ocean. Like other Pacific Salmon, chums return to spawn in the stream or river where they were born, and after spawning, they die.

Juvenile chum salmon eat crustaceans, insects, and young herring. Adults feed on copepods, tunicates, mollusks, and fish. When adults return to fresh water to spawn, they stop eating, and their digestive tract deteriorates.

Chum salmon rank second to pink salmon in average annual catch in Alaska’s commercial fishery. Chum-salmon meat is commercially the least valued of the salmon species, and commercial fishermen are paid less or the same for chums as they are for pink salmon. Chum-salmon eggs, though, are the largest and most valuable of any salmon eggs and are sold in Japan as ikura salmon caviar. Chums are not usually targeted by sports anglers because they rarely aggressively attack a lure.

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Is a serial killer stalking women on Kodiak Island? My novel,  The Fisherman’s Daughter, is available for pre-order!


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Pink Salmon (Oncorhynchus gorbuscha)


Pink salmon (Oncorhynchus gorbuscha) are also sometimes known as humpback salmon, or “humpies,” due to the hump males develop on their backs before they spawn. Pink salmon are the smallest of the five species of Pacific salmon found in Alaska. They average between 3.5 and 5 lbs. (1.6-2.3 kg) in weight and are usually between 20 and 25 inches (51-63 cm) long.

Young pink salmon are completely silver with no parr marks or spots. In their ocean phase, adult pink salmon are steel blue to blue green on the back and have silver sides and a white belly. As they get closer to fresh water, males develop large, black spots on the back, the adipose fin, and on both lobes of the caudal fin (tail). When they return to fresh water to spawn, males turn dark on the back and are red with olive blotches on the sides. They have a bright white belly. Females are similarly but less-distinctly colored. In their ocean phase, pink salmon have an elongate, fusiform shape, but when a male returns to fresh water, he develops a large hump on his back, an enlarged head with big teeth, and hooked jaws called a kype. These morphological changes allow a male to fight off other males once he has chosen a breeding partner.

Pink salmon are the most numerous Pacific salmon. They occur naturally throughout the coastal waters of the North Pacific Ocean, Arctic Ocean and nearby seas. In North America, pink salmon have been found in small numbers as far south as north-central California, but they are more common from Puget Sound northward. They also occur to the west from the Lena River in Siberia south to Korea and Kyushu, Japan. Pink salmon have been introduced to the Great Lakes. In Alaska, pink salmon are abundant along the coast.

Pink salmon complete their entire life cycle within two years, the shortest life cycle of any Pacific salmon. Because the life span is two years, fish born in an odd-numbered year do not interbreed with fish born in an even-numbered year, creating genetically distinct odd-year and even-year populations. Even if salmon spawn in the same stream, odd-year and even-year fish will never interbreed, and often, either the odd-year or even-year population in a stream will produce more fish.

Salmon eggs incubate in the gravel of a stream over the winter and hatch either in the late winter or early spring. The alevin that emerges from the egg remains under the gravel, receiving nutrients from the large yolk sac attached to its belly. Once it depletes its yolk sac and emerges from the gravel, the fry swims downstream to the ocean and begins eating plankton and larval fishes.

Eighteen months later, the adult salmon returns to the stream or river where it was born to spawn. It arrives back at the stream sometime between late June and mid-October, depending on the stream and the population. Once they reach their spawning stream, both males and females stop eating, and they change from their sleek, silver marine phase to their spawning coloration and morphology. A male develops hooked jaws and a hump on his back, and his head and teeth enlarge.

A spawning female chooses a suitable nesting spot in the gravel and prepares a nest by turning on her side, pressing her tail against the stream bottom, and giving several vigorous flaps with her tail. She repeats this action several times to dig a shallow hole. She then settles into the hole to deposit her eggs, and her male partner joins her to fertilize them, using his hooked jaw and large teeth to fend off any other would-be suitors. A female may dig as many as four nests. She digs the second nest upstream from the first nest, covering the eggs in the first nest with the gravel she dislodges while digging the second nest. A group of nests is called a redd. The female defends her redd until she dies, usually two weeks after spawning. All pink salmon die after they spawn.

A female pink salmon lays between 1200 and 1900 eggs. Pink salmon have a tough life. If a fry is lucky enough to make it downstream to the ocean, it faces a mortality rate of 2% to 4% per day for the first forty days. Young salmon provide food for birds, fish, invertebrates, and other predators. Studies show after forty days, the mortality rate drops to .4% to .8% per day. Once a salmon heads back to coastal waters and its natal stream, it must avoid humans, sharks, killer whales, seals, sea lions, river otters, eagles, and every fish larger than it is. When it reaches its birth stream, it becomes prey for bears, eagles, human anglers, and other predators.

Pink salmon mostly spawn in small streams and rivers near the coast, and most do not travel more than forty miles upstream to spawn. In large river systems, though, they sometimes travel further. Pink salmon have been documented swimming 130 miles (209 km) up the Susitna River in Southcentral Alaska, and they have been seen spawning 250 miles (402 km) up the Mulchatna River.

In the ocean, pink salmon eat plankton, small fish, squid, and an occasional aquatic insect. Their flesh gains its pink color from the tiny marine crustaceans they eat.

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Next week, I’ll write about the commercial and sports fisheries for pink salmon. While pink salmon may be the least flashy of the salmon species, they are known as the bread and butter of the salmon commercial fishing industry.

I will soon be releasing my next novel, The Fisherman’s Daughter, so check back often for updates on its release. Also, be sure to sign up for my monthly mystery newsletter. Newsletter subscribers will be the first to hear about the release of my new novel.

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Pacific Salmon


Five species of Pacific salmon return each summer to breed in Alaskan streams, rivers, and lakes. I will admit salmon are confusing fish. Not only do they have some of nature’s most complicated life cycles, but each species of Pacific salmon is known by two different common names. Are Atlantic and Pacific salmon the same fish? Which species of Pacific salmon is worth the most money to commercial fishermen? Do the various species taste different? Which species of salmon freezes the best? Why do some species grow larger than others, and why do salmon jump when they return to spawn?

Over the next few weeks, I hope to answer the above questions while I profile each of the five species. In this post, I will give you a generic overview of salmon and describe the life cycle of a Pacific salmon.

Pacific salmon and Atlantic salmon belong to the same family but not to the same genus. Atlantic salmon are more closely related to some species of trout than they are to Pacific salmon. One big difference between Pacific and Atlantic salmon is Pacific salmon only breed once, and then they die. Atlantic salmon return to freshwater to breed many times before they die.

The five species of Pacific salmon are pink salmon, also known as humpies; chum salmon, also known as dog salmon; red salmon, also known as sockeyes; silver salmon, also known as coho; and king salmon, also known as chinook. The five species look very similar to each other in their marine ocean phase, but once they enter fresh water, salmon go through significant physical changes, and each species has distinctive markings.

Fertilized salmon eggs incubate in the gravel of a river or lake bed for a length of time that varies depending on the species as well as other factors. Once the egg hatches, it is called an alevin. An alevin is small and has a relatively large, orange yolk sac attached to its body. The alevin receives its nutrients from the yolk sac and remains hidden from predators in the safety of the gravel bottom of the stream or lake. As the alevin grows, it depletes the nutrients in the yolk sac and begins to develop mouth parts.

Once the yolk sac is depleted, the young salmon leaves the safety of the gravel bed and must search for its food. At this point in its life cycle, the fish is called a fry. Except for pink salmon, a fry has parr marks along each side of its body. These marks provide camouflage to protect the fry from predators. Fry eat food such as insect larvae and plankton.

This is where the life cycle begins to get complicated. Fry remain in fresh water for a length of time which not only varies between species but may also vary between populations of the same species. Sockeye and silver salmon usually remain in fresh water for one or two years, while pink and chum salmon migrate to sea soon after they emerge from the gravel. King salmon fry usually stay in fresh water for one year.

Before salmon migrate to the ocean, they lose their parr marks and turn silver in color. At this stage of their lifecycle, they are called smolt. Once smolt leave their freshwater stream, they spend a great deal of time in brackish water where freshwater streams flow into the ocean. They feed and grow in the brackish water until they reach a certain size, and then they migrate to the ocean. Once they enter the marine phase of their lifecycle, they are considered adult salmon.

Adult salmon remain in the ocean for a variable amount of time, depending on the species and the population. King salmon can stay in the ocean for as long as six years, but pink salmon return to freshwater to spawn when they are only two-years-old. Once adult salmon return to freshwater, they undergo a dramatic physical change. Sockeye salmon, king salmon, and silver salmon turn dark red, while chum salmon develop calico bands on each side of their bodies. Pink salmon turn dark, and males develop a hooked jaw and a large hump on their back.

Salmon return to the stream or lake where they were born to spawn and die. At this point in their lifecycle, they are called spawners. Once the salmon reach their spawning grounds, a male and female form pair bond. The female digs a bed, called a redd, for the eggs in the gravel. She deposits her eggs in the redd, and the male swims over the eggs and fertilizes them with his sperm. She then brushes a light coating of gravel over the eggs. Once they spawn, all species of Pacific salmon slowly deteriorate and die, their bodies left to fertilize the stream or lake where they were born, ensuring the birthing grounds will remain rich in nutrients for future generations.

Every year, I watch salmon return to their natal streams to spawn. This summer, we had a huge return of pink salmon to the many streams on Kodiak Island, and at times when I sat on our boat, salmon surrounded me, jumping out of the water as far as I could see, reminding me of popcorn. I am always amazed by the incredible life cycles of Pacific salmon and how the many animals and plants on Kodiak Island depend on salmon to survive and thrive. As they return from the ocean, salmon are chased by humans, bears, eagles, seals, sea lions, sharks, and any fish big enough and fast enough to catch them. It is a wonder any salmon survives the gauntlet it must swim to reach its birth area and reproduce. Once it spawns and dies, the body of a salmon provides nutrients for the stream or lake bed and the plants and trees growing in the vicinity. It is impossible to imagine a Kodiak riparian ecosystem without salmon.

Next week, I’ll write about pink salmon, the smallest but one of the most important of the five Pacific salmon species.

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