Entiat National Fish Hatchery
Pacific Region


Former SCEP student holding an adult coho salmon - Photo: USFWS
Former SCEP student holding a coho salmon.

  • Pacific Salmon live to spawn one time—after that, they die. In contrast, steelhead can migrate to and from the ocean and spawn more than once.
  • Chinook salmon are also known as "Tyee" or "King" salmon
  • The largest Chinook salmon on record was caught in Alaska and weighed 126 pounds.
  • Fish secrete mucus, slime coating, to protect it against parasites & disease, cover wounds & prevent infection, and to move faster through the water.
  • The gravel nest that a female salmon creates with her tail is called a redd.
  • The shape of a redd creates a natural baffle that causes upwelling water currents, bringing oxygen to eggs.
  • A female Chinook salmon can lay up to 7,000 eggs.
  • 10% to 20% of fertilized wild eggs survive through early life stages in the wild, 80% to 100% in a hatchery.
  • Salmon eggs come with their own self-contained food source—their yolk
  • The mottled coloring of fry matches their stream environment, camouflaging them from predators.
  • Fish don't have ears.  They hear or feel vibrations along the lateral line of their bodies.
  • As fingerlings mature into smolts, their bodies turn a shiny silver color that provides better camouflage in the open ocean.
  • Smolts migrate downstream tail first—scientists are not sure why. One theory is that oxygen rich water can more easily flow into the gills of the fish; or maybe salmon orient themselves based on their natural instinct to swim upstream.
  • In saltwater, fish drink constantly and rarely urinate - salty urine. In fresh water, fish rarely drink and urinate constantly - dilute urine. This maintains the salt balance in their bodies.
  • After reaching the ocean, a salmon can double its weight in just one summer.
  • Over 20 species of animals, such as bears and eagles, eat spawned-out salmon carcasses; the carcasses bring ocean nutrients and minerals to the terrestrial world, thus nourishing the watershed.
  • Fossils show that fish existed over 400 million years ago.
  • Only about 1% of all Earth’s water is fresh water.
  • Scientists can tell how old a fish is by reading the growth rings on the fish scales. (almost just like tree rings)
  • A person who studies fish is called an ichthyologist.
  • Steelhead and rainbow trout are the same species, but rainbow trout are freshwater fish only, while steelhead are anadromous, meaning they go out to sea.
  • Salmon have teeth on the roof of their mouth, tongue, jaws and throat. These help prevent prey from escaping.  

Fun Fish Facts comes from a variety of sources, including FWS publications

Chinook Salmon - Photo: USFWS
Chinook Salmon
Coho Salmon - Photo: NMFS Northwest Fisheries Science Center
Coho Salmon
NMFS Northwest Fisheries Science Center
Rainbow Trout - Photo: USFWS
Rainbow Trout
Pacific Lamprey - Photo: USFWS
Pacific Lamprey
Bull Trout - Photo: USFWS
Bull Trout
Aquatic Invasive Species Zebra Mussels - Photo: USGS
Aquatic Invasive Species (AIS) Zebra Mussels

Last updated: September 5, 2014

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