TROUT

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TROUT

• Produced by Kim Tisdale
• Fisheries Biologist
• Nevada Department of Wildlife
• 2004

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Salmon Family

• Scientific Family name is Salmonidae
• Includes three subfamilies
• Salmon, Trout, and Char
• Whitefish
• Grayling

• Economically the most important family of cold
  water fishes in North America
• Sport Fisheries
• Commercial Fishing
• Hatcheries and Fish Farms

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Salmon Species

• Pacific Salmon
• Pink or Humpback
• Chinook or King
• Coho or Silver
• Chum or Dog
• Sockeye or Red
• Atlantic Salmon
• Atlantic Salmon

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Salmon

• Anadromous
• Spends its life in the ocean but returns to fresh
  water to spawn
• Pacific Salmon die shortly after spawning
• Atlantic Salmon may live to spawn two or more
  times

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Kokanee Salmon
Landlocked Sockeye Salmon are called Kokanee
Salmon.
Kokanee were originally stocked into Lake Tahoe
in 1950. Every fall, thousands of kokanee ascend
Taylor Creek (Tahoe tributary) to spawn.
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Trout and Char
Photo courtesy of Mike Sevon
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Trout Facts

• All salmonids are characterized by the presence
  of an adipose fin
• All salmonids require clean, cold water in which
  to live and have a low tolerance to habitat
  degradation.
• Primarily freshwater fish, however, many species
  develop seagoing races.
• Can you name the anadromous form of the rainbow
  trout?

Steelhead
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True Trout

• Characteristics
• Black spots on light background
• Stream obligate spawners
• Nevadas True Trout
• Cutthroat
• Rainbow
• Brown

Photo courtesy of Mike Sevon
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Char

• Characteristics
• Light spots on dark background
• Prefer colder water than trout
• Spawn in the fall
• Can spawn in a lake environment
• Nevadas Chars
• Lake Trout
• Brook Trout
• Bull Trout

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Can You Name the Trout Native to Nevada?

• Cutthroat Trout
• Lahontan (Threatened species)
• Bonneville
• Yellowstone
• Bull Trout
• Threatened species
• Redband Trout
• Inland rainbow trout

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Lahontan Cutthroat Trout
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Cutthroat Trout

• Once the predominant native trout in lakes and
  streams across the Great Basin
• Competition with non-native trout and habitat
  degradation can be attributed to the decline in
  the species
• Recovery activities by NDOW and other agencies
  are ongoing to reestablish these fish in their
  historic range
• Official State Record Cutthroat Trout
• 23 pounds 8 ounces (Pyramid Lake, 1977)
• Unofficial Record 41 pounds (Pyramid Lake, 1925)

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Rainbow Trout
Photo courtesy of John Rupp
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Rainbow Trout

• The most important trout in North America based
  on its contribution to sport fisheries
• Comprise over 90 of the hatchery production from
  Nevadas four hatcheries
• Rainbow are native to waters along the Pacific
  coast
• All rainbow trout existing in Nevada are
  introduced with the exception of the Redband
  Trout which can be found in 12-mile Creek in the
  Northwest corner of Nevada
• State Record 16 pounds 4 ounces (Lake Mohave,
  1971)

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Brown Trout
Photo courtesy of Mike Sevon
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Brown Trout

• Imported from Europe in the late 1800s and
  stocked throughout the United States. They were
  first introduced into the Truckee River in 1895.
• Often described as the wariest and hardest to
  catch of all trout
• While they prefer colder water, brown trout can
  tolerate temperatures as warm as 75F and can be
  found in slower moving water that would be
  unsuitable to other trout
• State Record 27 pounds 5 ounces (Cave Lake, 1984)

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Brook Trout
Photo courtesy of Mike Sevon
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Brook Trout

• Native to the Eastern U.S.
• Stocked extensively throughout the U.S.
  approximately 100 years ago.
• Usually found inhabiting high mountain lakes and
  streams due to their preference for cold water
  (rarely found where temps exceed 65F.)
• Popular with anglers considered the easiest
  trout to catch and the best tasting
• State Record 5 pounds 10 ounces (Bull Run
  Reservoir, 1980)

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Lake Trout (Mackinaw)
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Lake Trout (Mackinaw)

• Native range is the northern portion of North
  America from Alaska to Labrador and includes the
  Great Lakes
• Highly prized as a sport fish due to its large
  size (World Record 72 pounds 4 ounces)
• Generally only found in deep, cold lakes
• In Nevada, theyre found in Lake Tahoe where they
  have been reported at depths as deep as 1,400
  feet
• State Record 37 pounds 6 ounces (Lake Tahoe,
  1974)

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Bull Trout
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Bull Trout

• Native to the Jarbidge River system north of
  Elko.
• The Jarbidge is a tributary to the Snake River in
  Idaho, however, the populations are separated by
  150 miles of unsuitable trout habitat and several
  impassable dams.
• Federally listed as Threatened
• State Record 4 pounds 6 ounces (Jarbidge River
  WF, 1985)
• World Record 32 pounds 0 ounces (Lake Pend
  Oreille, Idaho)

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Life Cycle of Salmon and Trout
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Spawning
Spawning occurs in the spring for Rainbow and
Cutthroat All other Nevada salmonids are fall
spawners
Female seeks out a suitable location for her nest
and begins digging her redd
Video footage courtesy of Manu Esteve, University
of Washington
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Factors Influencing Nest Location

• Water Temperature
• Depth
• Velocity
• Substrate
• Cover for maturing fish
• Size of Spawners (Larger fish may choose larger
  streams with bigger substrate)
• Trout and Char often spawn in the transition area
  between pools and riffles where water velocity is
  accelerating.

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Spawning
Males will fight for spawning rights to the
female. The most dominant male will spawn. The
process of courtship and nest building will last
for hours Only when the female is ready will
spawning commence.
Video footage courtesy of Manu Esteve, University
of Washington
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Spawning
When the female is ready, she will signify the
male by arching her back and quivering over the
redd. The male will join her and they both open
their mouths and release their eggs and
sperm. The female immediately begins to bury the
newly laid eggs.

Video footage courtesy of Manu Esteve, University
of Washington
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Egg Development
Females can lay between 200 to 8,000 eggs
(depending on the size of the fish).
Eggs are extremely vulnerable to predators,
suffocation and fungus spores. Egg development
depends entirely on water temperature Rainbow
trout eggs will hatch in about three weeks at a
water temperature of 54F.
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Alevin Development
Newly hatched trout have a yolk sac that
nourishes the young fish until it is mature
enough to feed itself. Sac fry remain in the
gravel until their yolk sack is absorbed.
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Fry Development
Once it is buttoned-up, the fry will work their
way through the gravel to the top of the stream
bed. These swim-up fry dart to the surface and
gulp air to fill their air bladders. From this
point, they are free swimming fish and begin to
feed.
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Juvenile Development

• To reach maturity a juvenile fish must
• avoid predators,
• Find adequate food
• Survive summer heat and winter cold

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Adult
Lahontan Cutthroat Trout Pyramid Lake
Only about 2 of fertilized eggs survive to
become mature adults. Most salmonids reach
sexual maturity at 3 to 5 years. Some precocious
fish (usually males) mature at 2 years.