Before we tackle that, though, a larger question: why do they do it? The ultimate purpose for salmon to return to their home streams and rivers is to reproduce and ensure the survival of their offspring.
Simple enough. But why is returning to the natal site part of the process? Consider the alternative: swimming upstream to just any old river could have some pitfalls. It may not have mates of the same species. Or conditions might not favor that type of salmon. For all these reasons, we can see why salmon navigate their way home.
Pink salmon are also called humpback salmon due to the physical changes the males go through when spawning. They grow large humps on their backs and turn bright pink before dying. No pink salmon survive after they swim upstream. Chum salmon are probably the least targeted species by sports fishermen, but they also migrate upriver to spawn. They grow larger than pink and sockeye salmon, with their average adult weight clocking in at around 12 to 15 lbs.
Now that you know why salmon congregate in mass numbers each fall, you probably want to know how you can catch them. There are many different ways to catch salmon. If you want to learn more check out the articles we linked above.
Troll for salmon in the inlets and bays that the salmon spawning rivers dump into. These areas are usually great for salmon from late August to early November depending on when it starts to rain frequently. Use a hoochie squid or a cut plug herring and drop your bait down to 20 feet. You can do this with weights or a downrigger if you have one. Troll at 2 to 3 miles per hour, or slightly faster for coho salmon.
Once you start getting bites a certain depth, switch them all to that depth. Once the salmon run season gets going usually in late September through October , we like to switch to back trolling in rivers with a jet boat. When back trolling, you can skip the downrigger for weights or a diver. We like to back troll with either a Kwikfish or salmon roe.
Check out our detailed article on how to fish with salmon roe as bait as well as why salmon eat salmon eggs for more info. When salmon are in high numbers in rivers, you can also cast for them with beads or bright colored spinners. They are very territorial during this time period and will lash out at annoying lures. Salmon are powerful fish and will easily overpower a small spinning rod and reel. For both king and coho salmon, we recommend a medium to heavy saltwater spinning reel with 30 lb test braided line.
Check out our guide on the best saltwater spinning reels for more info. Using a long rod 8 ft and over give you more leverage to fight a strong salmon while trolling.
It also adds to the flexibility of the rod so when a salmon bites your lure while trolling it gets hooked effectively. Salmon rods need to be more flexible than other rods, especially at the tip. A salmon can detect one drop of water from its home stream mixed up in gallons of sea water. Salmon will follow this faint scent trail, with the aid of the other methods mentioned above, back to their home stream to spawn.
Although a single female salmon can lay 1, to 17, eggs, very few of those eggs actually survive from fertilization to maturity. An average of 3 fish returning for every parent fish that spawns would be considered good production. Many natural and human-related factors cause this high mortality. During spawning eggs may not be fertilized, or may not get buried in the gravel before they are either eaten by predators birds and fish or become damaged as they bounce along the river bottom.
Some eggs may not mature and hatch due to freezing, drying out if the water level drops too low, being trapped in the gravel, or being smothered by silt. Those eggs that successfully hatch to "alevin" stage continue to grow, and then emerge from the gravel as "fry. Pink and chum salmon juveniles head out to sea immediately. The other species may spend as many as two years in freshwater before they head out to sea.
During times of these seaward migrations you can find corresponding concentrations of predators, such as beluga whales, arctic terns, gulls, and other fish species.
Salmon reach sexual maturity at 2 to 8 years old. Different species mature at different rates. See below for information on the spawning of each of the five salmon species on Togiak Refuge.
When the adult salmon are ready to spawn, after their long journey homeward, they select spawning sites with water flow through the gravel which will provide oxygen for their eggs and carry away carbon dioxide.
Once a female salmon selects a spawning site, she rapidly pumps her tail to wash out a depression in the stream gravel. After the eggs are laid, the female uses the same tail movements to completely cover the eggs with gravel. These gravel nests in which the salmon deposit their eggs are known as redds. Over several days, females may lay several more redds in a line upstream. A single spawning Chinook female can lay up to 17, eggs!
The eggs hatch after weeks. Hatching times are influenced by water temperature, levels of oxygen and carbon dioxide, and vary for the different species. A newly hatched salmon is called an alevin. Boulders, logs, shade, and access to side channels is important in allowing fry to hide from predators and prevents them from getting flushed downstream during flood river-flows.
By the end of their seaward migration, the smolts are silvery all over. At this time, smolting begins, and scales grow as they turn a silvery color.
At night to avoid predators, small fry or developing smolts allow the river to take them tail-first downstream while larger fry swim actively towards the ocean. Estuaries, at the mouth of the river, are crucial to the survival of young smolts. While allowing their bodies to adjust to the new conditions, they feed heavily, hoping to ensure survival in the ocean. Estuaries provides crucial adjustment habitat for salmon leaving and entering the river. Salmon may spend one to seven years in the ocean.
Certain species have more flexible life history strategies, while others are more rigid. Chum may spend up to seven years at sea, but typically four. Pink salmon, on the other hand, spend a fixed 18 months at sea. Sockeye typically spend two years at sea, coho spend about 18 months, and chinook can spend up to 8 years before journeying back to their natal streams to spawn.
Coho return to spawn in the Sol Duc River. Once the salmon reach freshwater, they stop feeding.
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