Pumpkin salmon has been an important fishery object for many decades, it has taken a leading position in terms of catch volumes among all salmon. Having excellent taste, nutritional characteristics of meat and caviar, combined with a relatively low cost, this type of fish is in constant demand on the world food market.
Origin of the species and description
Pink salmon — a typical representative of the salmon family, characterized by relatively small size and high prevalence in the cold waters of the oceans and seas. Refers to anadrobnyh fish, which are characterized by reproduction in fresh waters, and living in the seas. Pink salmon got its name due to the peculiar hump on the back of males, which is formed with the onset of the spawning period.
Video: Pink salmon
The most ancient ancestor of the pink salmon that exists today was small in size and resembled the freshwater grayling that lived in the cold waters of North America more than 50 million years ago. The next three tens of millions of years did not leave any noticeable traces of the evolution of this species of salmon fish. But in the ancient seas, in the period from 24 to 5 million years ago, representatives of all the salmon-like species that exist today, including pink salmon, were already found.
Interesting fact: All pink salmon larvae when born are females and just before rolling into the waters of the sea, half of them change their sex to the opposite. This is one of the ways of the struggle for existence, which nature has provided this species of fish. Since females are more hardy due to the characteristics of the organism, thanks to this “transformation”, a greater number of larvae will survive until the moment of migration.
Now you know what pink salmon fish looks like. Let's see where it lives and what it eats.
Appearance and Features
Pink salmon has an elongated body shape, characteristic of all salmonids, slightly compressed on the sides. The conical head is small in size with small eyes, while the head of males is longer than that of females. The jaws, lingual and palatine bones, the vomer of pink salmon are studded with small teeth. The scales easily fall off the surface of the body, very small.
The back of the oceanic pink salmon has a blue-green color, the sides of the carcass are silvery, and the belly is white. When returning to spawning grounds, pink salmon becomes pale gray, and the lower part of the body acquires a yellow or greenish tint, dark spots appear. Immediately before spawning, the color darkens significantly, and the head becomes almost black.
The body shape of the females remains unchanged, while the males change their appearance significantly:
- the head lengthens;
- a row of large teeth appears on the elongated jaw;
- a rather impressive hump grows on the back.
Pink salmon, like all representatives of the salmon family, has an adipose fin located between the dorsal and caudal fins. The average weight of an adult pink salmon is about 2.5 kg and the length is about half a meter. The largest specimens weigh 7 kg each with a body length of 750 cm.
Distinctive features of pink salmon:
- this species of salmon has no teeth on its tongue;
- the mouth is white and there are dark oval spots on the back;
- the caudal fin is V-shaped.
Where does pink salmon live?
large quantities in the North Pacific:
- Along the Asian coast — from the Bering Strait to Peter the Great Bay;
- along the American coast — to the capital of California.
This type of salmon lives off the coast of Alaska, in the Arctic Ocean. Pink salmon is found in Kamchatka, the Kuril Islands, Anadyr, the Sea of Okhotsk, Sakhalin and so on. It is found in the Indigirka, the lower reaches of the Kolyma up to Verkhne-Kolymsk, it does not enter the Amur high, it does not occur in the Ussuri. The largest herds of pink salmon live in the Pacific Ocean, where American and Asian herds mix during feeding. Pink salmon is found even in the waters of the Great Lakes, where a small number of individuals got by accident.
Pink salmon spends only one summer season and winter in the sea, and in the middle of the second summer goes to the rivers for subsequent spawning. Large individuals are the first to leave the waters of the seas; gradually, during the course of migration, the size of the fish decreases. Females arrive at the spawning site later than males, and by the end of August, the pink salmon run stops, and only fry return to the sea.
Interesting fact: The most impressive representative of the ancient salmon family is the extinct “saber-toothed salmon”, which weighed more than two centners, was about 3 meters long and had five-centimeter fangs. With its rather formidable appearance and impressive size, it was not a predator, and the fangs were only part of the “marriage attire”.
Pumpkin salmon feels great in cold waters with temperatures ranging from 5 to 15 degrees, the most optimal is about 10 degrees. If the temperature rises to 25 or more — pink salmon is dying.
What does pink salmon eat?
Adult individuals actively eat mass groups of plankton and nekton. In deep-sea areas, the diet consists of juvenile fish, small fish, including anchovies, squid. Near the plume, pink salmon can completely switch to feeding on larvae of benthic invertebrates and fish. Just before spawning, feeding reflexes disappear in the fish, the digestive system completely atrophies, but, despite this, the grasping reflex is still fully present, therefore, during this period, catching fish with a spinning rod can be quite successful.
Interesting fact: It has been noticed that in even years in Kamchatka and the Amur, pink salmon is smaller than in odd years. The smallest individuals have a weight of 1.4-2 kg and a length of about 40 cm.
Young animals feed mainly on a variety of organisms that live in abundance at the bottom of reservoirs, as well as plankton. After exiting the river into the sea, small zooplankton becomes the basis for feeding young individuals. As the young grow, they move on to larger representatives of zooplankton, small fish. Despite their small size compared to their relatives, pink salmon has a faster growth rate. Already in the first summer season, the young individual reaches a size of 20-25 centimeters.
Interesting fact: Due to the high commercial value of pink salmon, in the middle of the twentieth century, several attempts were made to acclimatize this species of salmon in the rivers off the Murmansk coast, but they all ended in failure.
Features of character and lifestyle
Pink salmon is not tied to a specific habitat, it can be many hundreds of miles away from its place of birth. Her whole life is strictly subordinated to the call of procreation. The fish age is short – no more than two years and it lasts from the birth of a fry to the first and last spawning in life. The banks of the rivers where pink salmon come to spawn are literally littered with the carcasses of dead adults.
Being an anadromous migratory fish, pink salmon feeds in the waters of the seas and oceans and enters the rivers for spawning. For example, in the Amur, pink salmon begins to swim immediately after the ice melts, and by mid-June the surface of the river is simply teeming with the number of individuals. The number of males in the incoming flock prevails over females.
The migrations of pink salmon are not as long and long as those of chum salmon. They occur in the period from June to August, while the fish do not rise high up the river, preferring to be located in the riverbed, in places with large pebbles and with the strongest water movement. After spawning is completed, the producers die.
All salmon, as a rule, have an excellent natural “navigator” and are able to return to their native waters with incredible accuracy. Pink salmon was unlucky in this regard — its natural radar is poorly developed, and for this reason it sometimes enters places that are completely unsuitable for spawning or life. Sometimes the whole huge flock rushes into one river, literally filling it with their bodies, which naturally does not contribute to the normal spawning process.
Social structure and reproduction
Pink salmon lays eggs in parts in a pre-prepared nest-depression at the bottom of the reservoir. She digs it with the help of a caudal fin and digs it in after spawning and fertilization are over. In total, one female is capable of producing from 1000 to 2500 eggs. As soon as a portion of eggs is in the nest, the male fertilizes it. There are always more males than females in the riverbed, this is due to the fact that each batch of eggs must be fertilized by a new male in order to pass on the genetic code and fulfill their life mission.
The larvae hatch in November or December, less often The process is delayed until January. Being in the ground, they feed on the reserves of the yolk sac, and only in May, leaving the spawning mound, the fry roll into the sea. More than half of the fry die during this journey, becoming the prey of other fish and birds. During this period, the young have a silvery uniform color and a body length of only 3 centimeters.
After leaving the river, pink salmon fry tend to the northern part of the Pacific Ocean and stay there until next August, thus, the life cycle of this fish species is two years, and that is why there is a two-year periodicity in the change in the abundance of this salmon species. Puberty in pink salmon occurs only in the second year of life.
Natural enemies of pink salmon
Pink salmon in its natural environment there are more than enough enemies:
- caviar is destroyed in huge quantities by other fish, such as char, grayling;
- gulls, wild ducks, predatory fish are not averse to feasting on fry;
- adults are included in the habitual diet of belugas, seals, herring sharks;
- bears, otters, birds of prey eat them in spawning grounds.
An interesting fact: More than 37 percent of the world's catches of Pacific salmon come from pink salmon. The global catch of this type of fish in the 1980s averaged 240,000 tons per year. The share of pink salmon in the total salmon fishery in the USSR was about 80 percent.
In addition to enemies, pink salmon has natural competitors that can take on some of the food familiar to salmon fish. Under certain circumstances, pink salmon itself can cause a decrease in the population of other species of fish or even birds. Zoologists have noticed a connection between the increased population of pink salmon in the North Pacific Ocean and the decline in the number of slender-billed petrels in the Southern Ocean. These species compete with each other for food in the north, where petrels stop for the winter. Therefore, in the year when the pink salmon population grows, the birds do not receive the required amount of food, as a result of which they die during the return to the south.
Population and species status
In the natural habitat, periodic significant fluctuations in the abundance of pink salmon are observed. Most often this is due to the special cyclicity of their life, natural enemies do not have a significant impact on the population of this species of salmon. There is no risk of extinction of pink salmon, even despite the fact that it is the most important object of the fishery. The status of the species is stable.
In the North Pacific Ocean, the population of pink salmon (in the years of its peak, depending on the cycle of reproduction) has doubled compared to the 1970s. This was influenced not only by natural growth, but also by the release of fry from incubators. Farms with a full cycle of pink salmon cultivation do not currently exist, which makes it even more valuable for the end consumer.
Interesting fact: Canadian scientists have found that the proximity of wild pink salmon spawning sites to farms farming of other salmon fish causes significant damage to the natural population of pink salmon. The reason for the mass death of young animals is special salmon lice, which the fry pick up from other members of the family during a run into the sea. If the situation is not changed, then in four years only 1 percent of the wild population of this salmon species will remain in these areas.
Pumpkin salmon is not just nutritious and tasty, as perceived many inhabitants meet fish on the shelves of fish stores, in addition to everything, pink salmon is an incredibly interesting creature with its own special way of life and behavioral instincts, the main purpose of whose existence is to follow the call of procreation, overcoming all obstacles.