Wild salmon life cycle -
Alaska salmon have a most interesting life. One that takes them from the rivers and streams of Alaska's wild frontier, to the high seas of the Pacific Ocean, and back again. In fact, right back to the very place they were born. How they find their way back from the immensity of the Pacific Ocean is a small feat in itself.
Not to mention, that they swim from fresh water to salt water and back again. Starting out as small eggs in a stream bed, they hatch and begin their journey downstream towards the ocean. They spend a couple of years in the streams and rivers growing from small alevin to juvenile smolts.
At the mouth of the streams and rivers, the smolts school together and ready themselves for the trip out into the ocean.
During this time, their bodies change to adapt to the seawater. The young adult salmon then head out to sea and spend several years swimming in the Bering Sea and the Gulf of Alaska.
Once they have fully matured, they will swim back to their original stream or river where they re-adapt to the fresh water and swim back up the stream to reach their spawning grounds. Sometimes this means swimming up rugged rivers with miles of rapids and even waterfalls to leap.
Once they get back to their natal stream, they breed and lay their eggs. After spawning they generally die within a week, fertilizing the stream and creating a nutrient-rich environment for the new infant salmon that are about to hatch. Salmon are born in gravel nests at the bottom of stream and river beds in the form of a slightly translucent eggs about the size of a pencil eraser.
The eggs are usually red to pink in color and spherical in shape. During the 2 to 3 month period it take the eggs to hatch, their eyes and other organs can be seen developing through the translucent shell of the egg. When the salmon egg is ready to hatch, the baby salmon will break free of the egg's soft shell retaining the yolk as a nutrient-rich sac that hangs below it's body.
At this stage, they are called Alevin and are about one inch in length. During the next month, the alevin will remain hidden in the gravel nest and feed from the nutrient-rich yolk sac until it is completely absorbed. The tiny salmon leave their gravel nest and begin to swim and feed for themselves.
At this stage they are called Fry and take the form of tiny fish. It's also at this time that they start their journey downstream.
The first part of their journey is a difficult one as the small vulnerable fry must hide under rocks and among vegetation to avoid predators such as birds, insects, and other fish.
At the same time, they must find feed to survive. After several months, as the Fry feed and grow, they develop vertical markings on the flanks of their bodies. At this stage they are called Parr and are about six inches in length. Though a bit bigger they still must hide from predators and continue their journey towards the ocean.
Parr will continue to feed for 1 to 3 years before they are ready venture out into the ocean. At this point, the juvenile salmon loses its vertical markings on its body and turns silvery in color. Now considered Smolt, they will school together in large groups.
It's at this time that the young salmon will adjust their bodies to saltwater, allowing them to swim out into the Pacific Ocean to feed and grow into adult salmon. Inside the egg is an embryo and a yolk which feeds it. For a while, the embryo has enough oxygen inside the egg, but as it grows, it needs more.
Finally it reaches the breaking point and struggles free of its egg shell, though not yet discarding its yolk. It is now an alevin. They remain under the gravel for protection against predators until their yolk sac is fully absorbed. It is virtually impossible to see alevin in the wild.
Once it has absorbed its yolk, the alevin becomes a fry. Small and vulnerable, fry spend a lot of their time avoiding predators. They head for dark pools in protected spots e. When they feel the urge, they begin their migration toward the ocean see Species for the different migratory patterns that characterize each species.
To manage the transition between freshwater and saltwater, salmon fry must go through a physical change known as smolting. Smolting begins in freshwater and sees the young salmon through the estuaries and into the ocean when it is time.
Smolts have a silvery coating over their scales to camouflage them from predators and shield their bodies from fresh to saltwater. Salmon enter the ocean as young, or juvenile, adults and leave it as mature adults, ready to spawn.
The length of time salmon spend in saltwater depends on how old they were when they entered, their species, marine conditions, and other factors. Their travels in the ocean are similarly variable, and one of the least understood parts of their lives.
When they are sexually mature, salmon follow their homing instinct and travel back to their natal streams to spawn. It is an arduous journey, and only the toughest and luckiest salmon complete it.
Wild salmon life cycle Pacific salmon Lean Body Strategies cycle sal,on on the species. Some spend hardly any time Wild salmon life cycle Wuld Long-distance fueling strategies some spend years. Some mature at two salnon of age; some mature at five. Some live for only a couple of years; others live for ten. And some, like Steelhead and Cutthroat, can spawn more than once. Despite these variations, we can still make some general observations about the life stages of salmon. All Pacific salmon are anadromous, which means they start in freshwater streams, lakes, rivers, etc. xycle sockeye salmon Wild salmon life cycle a smart lige choice because it is sustainably Environmentally friendly farming and responsibly harvested under U. NOAA Fisheries works sakmon cooperation with Wild salmon life cycle, state, sqlmon, and Canadian Controlling hypertension naturally to manage samlon commercial, recreational, and tribal harvest of salmon and steelhead in ocean and inland waters of the West Coast and Alaska. To learn more about management of these fisheries, visit our West Coast and Alaska fisheries management pages. However, some sockeye salmon are also protected under the Endangered Species Act. Learn more about protected sockeye salmon. Reddest flesh of the wild salmon species. The raw meat has a bright-red or orange-red color.
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