Salmon: Top Ten Questions
Thanks to Jeff Heindel, Fish Hatcheries Supervisor, Idaho Department of Fish and Game; and Adare Evans, Wildlife Educator, Idaho Department of Fish and Game for their answers.
1: How many types of salmon are there?
In Idaho we have two types. We have chinook and sockeye salmon. There are five species in the eastern side of the Pacific Ocean: chinook, sockeye, coho, pink, and rainbow trout (which is technically trout). (From Naomi at Owyhee Harbor Elementary in Boise)
2: Why do salmon swim upriver to their birthplace?
They go back to their birthplace because they remember it. Salmon will hatch out of their nest and they stay in that stream for a while. When it's time for them to go to the ocean, they swim backwards, smelling the water the entire way. Water has smells to it based on the minerals in the water. Salmon smell the water in the stream where they were born, and they remember it. They follow that smell all the way back to their birthplace so they know where to lay their eggs. It seems to be an internal drive for them to go back to that particular spot. (From Alexander at Riverside Elementary School in Boise)
3: Why are salmon pink?
During their maturation phase, salmon will undergo a coloration change. The color change is more accentuated in the males because the coloration change helps them compete for the females. Diet is a factor in coloration too. A more natural diet of foods that contain a lot of pigment can color the flesh of the fish giving it a pink or red color. (From Lauren at Cynthia Mann Elementary School in Boise)
4: What do salmon eat?
They eat different things depending on their age. When they hatch, they have a built-in food supply consisting of a yolk on their belly. When that goes away and they are in the Idaho streams, they eat something called zooplankton. These are tiny organisms that we cannot see without a microscope. Once in the ocean, they switch from eating plankton and insects to eating fish or other things in the ocean, depending on the type of salmon. (From Jackson at Owyhee Harbor Elementary School in Boise)
5: How far can salmon swim?
They can swim a long distance. They swim several miles in a day. Their journey to the ocean and back is 600 to 900 miles each way. When they are in the ocean, they swim thousands of miles. (From Josie at Cynthia Mann Elementary School in Boise)
6: How fast does a salmon's heart pump?
How fast a fish's heart will pump depends on a lot of things. Is the fish excited? Is it being chased by a predator, or is it in a resting phase? Water temperature will also have a role in this. In cooler water, the salmon's heart slows down. The heart does not have to beat as fast to move blood around the body. (From Jameson at Riverside Elementary School in Boise)
7: Do fish have nostrils like people?
The two comma-shaped holes on each side of a salmon's head are its nostrils. These receptors absorb molecules from water and tell the fish what's going on in its environment. (From Maddy at Owyhee Harbor Elementary School in Boise)
8: What would happen if salmon went extinct?
Ecologically, it would be very, very detrimental. Salmon are important to the health of Idaho. When they go to the ocean, they eat and eat and eat, filling their bodies up with important nutrients. When they come back to Idaho and die, those nutrients act like fertilizer and help our streams and our plants. Also, their dead bodies feed so many other animals. They are a keystone species, meaning that they're at the top of an arch, supporting so many other things. If they went extinct, it would be detrimental to the plants and animals of Idaho. (From Braden at Cynthia Mann Elementary School in Boise)
9: How long can a salmon live?
In Idaho, the sockeye and chinook live about three to five years. If we go to the colder climates on the coast where growth is slower in fresh water, salmon can live up to eight years. (From Parker at Riverside Elementary School in Boise)
10: How much do salmon eat compared to their weight?
Salmon eat a fair amount. In the wild, they will consume large quantities of food. In general, much of that food - bugs and invertebrates - have a lot of water. The wild salmon take in a lot of food organisms to try to gain weight. In a hatchery, salmon will eat between three and six percent of their body weight a day. That's why salmon need a hatchery environment to maintain their base metabolism and to also have enough food to give them a bit of growth. (From Ethan at Cynthia Mann Elementary School in Boise)
Thanks to Brenda Beckley, Aquatic Education Supervisor, Idaho Department of Fish and Game; and Jeff Heindel, Fish Hatcheries Supervisor, Idaho Department of Fish and Game for their answers.
1: What is the most commonly caught and manufactured salmon in the United States? Is the species endangered?
In terms of numbers, that would be the pink or chum salmon. They are typically associated with the west coast (Washington, Canada and Alaska). Currently, they are not endangered. (From Tanner in Mrs. Schweitzer's class at Riverside Elementary School in Boise)
2: How do salmon go upstream if the water is going so fast?
Salmon are built like torpedoes and are very streamlined. They have a huge muscle and they use that muscle to swim upstream. After they use their muscle to get through a current, they may rest by stopping at a pool behind a rock or an eddy. (From Ellie who is home schooled in Eagle)
3: What is the difference between salmon and trout?
The basic difference between salmon and trout is that trout can spawn multiple times in their lifetime, while salmon spawn only once. (From Colby in Mrs. Nicolescu's class at Riverside Elementary School in Boise)
4: Why are salmon pink?
Salmon are not always pink. The sockeye salmon are very silver in color when they are adults in the ocean. It's when they migrate back to Idaho to spawn that they turn red and pink in color. Salmon are pink inside when you cook them because they eat a lot of krill, a type of shrimp. This helps them to be very, very pink when we eat them. (From Ryan in Ms. Chris' class at the Northwest Children's Home in Lewiston)
5: What is the biggest salmon in the world?
The largest species of salmon is the chinook salmon. Many people call them king salmon. They can be over 5 feet long and weigh over 100 pounds! (From Austin in Mrs. Woodall's class at Dalton Elementary School in Dalton Gardens)
6: What types of salmon are in the Snake River?
There are chinook salmon and steelhead, although steelhead are technically trout. Also, there are likely coho salmon that were reintroduced to Idaho by fish managers. (From Taylor in Mrs. Schweitzer's class at Riverside Elementary School in Boise)
7: How long can a salmon live?
The oldest salmon is typically the chinook. They can live to be eight or nine years old. They'll spend three or four years in fresh water, and may spend three or four years in salt water before they return back to spawn. (From Brian in Mr. Sasaki's class at Sage Valley Elementary School in Nampa)
8: How far can a salmon jump?
It depends on the habitat they are in. For example, if they have a large pool below a waterfall, they can get a burst of speed and certainly jump 10 feet or more. Also, they are very streamlined and muscular. This allows them to be strong and to jump quite a height. (From Morgan in Mrs. Gris' class at Horizon Elementary School in Boise)
9: What is the smallest salmon in the world?
As a species, the pink sockeye are the smallest salmon. However, residual males, who never go to the ocean and live their entire lives in fresh water are very small and may be no longer than a pencil. (From Aidan who is home schooled in Jerome)
10: How do you tell if a salmon is male or female?
It's difficult to tell the difference between a male and a female. The male species gets a little more color when they start to mature and get ready to spawn. Some of them will develop a hump and a hook jaw. Typically the females are not quite as colorful and they have rounder bellies. (From Owen in Mrs. Schultz's class at Dalton Elementary School in Dalton Gardens)
Click on a Topic:
- Ages Past
- Earth Science
- Human Body
- Science Fundamentals