Rainbow trout (Oncorhynchus mykiss)
Lake Huron (Fertilized Egg)
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1340 Temperature Example 0.3°2.0°C 965 943
Details
Viable eggs have resulted from December and January spawning at water
temperatures 0.3°-2.0°C in a tributary of Lake Huron.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1341 Temperature Lethal 0°4°C 965 943
Details
Eggs exposed to long periods of 0°-4°C temperatures suffered high
mortality and abnormalities.
Rainbow trout (Oncorhynchus mykiss)
(Fertilized Egg)
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
231 Wood Fiber Limit 346 109
Details
Although wood fiber in water did not affect hatching or survival of eggs,
it did reduce growth and survival of alevins. Fingerlings maintained in
water with 250 ppm of wood fiber had instantaneous growth rates of
0.00610.0062 compared to 0.02130.0345 in the control fish.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
239 Temperature Characteristic 400 109
Details
Incubation time varies with temperature: 101 days at 3.2°C, 75 days at 4.8°C,
44 days at 7.5°C, 29 days at 10.3°C, 27 days at 11.5°C, 25 days at 12.0°C,
21 days at 14.5°C, and 18 days at 15.5°C.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
277 Temperature Example 332 109
Details
Normal development was found to occur up to 10°C, compared to 13°C for
rainbows. Fingerling brown trout grew best at 13°C.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1372 Temperature Optimum 7°12°C 943 -
Details
The optimal temperature for embryo incubation is ~7°-12°C.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1373 Temperature Optimum 7°-12°C 1125 943
Details
Increased mortalities of rainbow embryos occurred at temperatures <7°C.
Normal development occurred at temperatures ³7°C but £12°C.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1374 Water Motion Optimum 3070 cm/s 963 943
667
Details 574
The optimal water velocity above rainbow trout redds is 30-70 cm/sec.
Velocities <10 cm/sec or >90 cm/sec are unsuitable.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1375 Phys. Assoc. Limit 1126 943
998
Details
In a 30% sand and 70% gravel mixture, only 28% of implanted steelhead
embryos hatched. Of the 28% that hatched, only 74% emerged.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1376 Phys. Assoc. Optimum 943 -
Details
Optimal spawning gravel conditions are assumed to include £5% fines. Low
survival of embryos and emerging yolksac fry are assumed to result in fines
³30%.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1377 Phys. Assoc. Optimum 963 943
996
Details 574
Suitable incubation substrate is gravel 0.3-10.0 cm. 966
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1400 Water Motion Limit 641 943
Oxygen Requirement >2.6 ppm 1005
1002
Details 1003
Water velocity may not be important for embryo hatching success if DO
concentrations around embryos >2.6 ppm.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1401 Depth Optimum 1002 943
Water Level Optimum 1003
Details
Depth may not be an important variable for egg incubation as long as eggs
are kept moist during incubation and redds are submerged when fry begin to
hatch and emerge.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1402 Temperature Optimum 7.2°10.0°C 986 943
Details
The highest survival rate for rainbow trout embryos was at a temperature
45°-50°F, low survival (15%-40%) at 59°F, and moderate survival at 37°-41°F.
Rainbow trout (Oncorhynchus mykiss)
(Juvenile)
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
277 Temperature Example 332 109
Details
Normal development was found to occur up to 10°C, compared to 13°C for
rainbows. Fingerling brown trout grew best at 13°C.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
290 Pred/Prey Example 298 109
Details
Fish (particularly small rainbow trout) were the principal foods of brown
trout in a Colorado reservoir.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
363 Wisconsin Pred/Prey Example 360 109
Details
Rainbow trout were more susceptible to pike predation than brown trout.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
567 Ontario Pred/Prey Example 144 110
Details
Small rainbow trout were eaten by largemouth bass shortly after trout were
stocked in an Ontario Lake.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
568 Arkansas Pred/Prey Example 185 110
Details
When rainbow trout (mostly >230 mm TL) were stocked in Lake Owachita,
Arkansas, 49% of bass >400 mm had trout in their stomachs when collected in
January and February. Ten of 11 bass >456 mm had eaten trout, but none of
51 bass <400 mm had eaten trout.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
899 Idaho Phys. Assoc. Optimum 567 555
Details
A substrate particle size of 10-40 cm offers excellent escape and winter
cover for trout fry and smaller juveniles.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1329 Pred/Prey Characteristic 943 -
Details
Adult and juvenile rainbow trout are opportunistic feeders and consume a
wide variety of foods.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1334 British Columbia Pred/Prey Characteristic 962 943
Details
Bottom fauna may comprise 83%-94% of the winter diet of adult and juvenile
lake rainbow trout.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1343 Movement Characteristic 943 -
Details
Rainbow trout residing in lakes and reservoirs have a similar life-history
pattern to steelhead trout, but generally lack a physiological smolt stage.
Juveniles migrate from natal streams to a freshwater-lake rearing area,
instead of to the ocean.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1344 Michigan Area of Water Characteristic 974 943
Details
Lake rainbow trout most commonly spend two summers in a stream and two
summers in a lake before maturing.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1347 British Columbia Movement Characteristic 991 943
Details
Whether spawning adults enter through an inlet or an outlet, they and their
progeny will return to the lake.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1354 Phys. Assoc. Requirement 943 -
Competitors Limit
Details
The feeding stations of dominant adult trout include overhead cover when
available. The feeding stations of subdominant adults and juveniles,
however, do not always include overhead cover. Antagonistic behavior
occurs at feeding stations and hierarchies are established. However,
escape cover is often shared.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1356 Phys. Assoc. Limit 943 -
Details
A cover area of ³25% of the total stream area provides adequate cover for
adult trout. A cover area of ³15% is adequate for juveniles.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1360 Oxygen Lethal ~3 mg/l 943 -
Details
The incipient lethal level of DO for adult and juvenile rainbow trout is
~3 mg/l or less (depending on environmental conditions, especially
temperature).
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1387 Phys. Assoc. Optimum 648 943
567
Details
Optimal size of substrate used as winter cover by rainbow fry and small
juveniles ranged from 10-40 cm in diameter.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1390 Temperature Optimum 15°20°C 964 943
Details
Metabolic rates are highest at 11°-21°C, with an optimal temperature of
~15°-20°C.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1391 Phys. Assoc. Characteristic 637 943
Details
Common types of cover for juvenile trout are upturned roots, logs, debris
piles, overhanging banks, riffles, and small boulders.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1392 Phys. Assoc. Optimum 943 -
Details
An area of cover ³15% of the total habitat area provides adequate cover
for juvenile trout.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1406 Utah Water Motion Characteristic 972 943
Details
The average mean column velocities occupied by juveniles in low to high
flows during random swimming were 0.40-0.56 fps in the winter and 0.43-
0.75 fps in the summer.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1407 Depth Characteristic 943 -
Details
Juvenile rainbow trout may occupy a wide variety of depths.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1408 Phys. Assoc. Optimum 943 -
Details
Cobble and boulders are suitable juvenile substrate.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1409 Temperature Avoid 229 943
Temperature Prefer
Details
Temperatures selected and avoided were a function of acclimation temperature.
Rainbow juveniles selected temperatures of 53°-72°F when acclimated to
43°-58°F. The lowest avoidance temperature was 41°F and the highest
avoidance temperature was 77°F at the given acclimation temperatures.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1410 Temperature Prefer 17.7°18.4°C 108 943
Temperature Avoid 13.9°, 22.2°C
Details
Preferred temperatures were 64°-66°F and 72°F, and avoidance temperatures
were 57° and 72°F.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1411 Temperature Lethal 28.8°C 943 -
Details
The critical thermal maximum for juveniles was 84°F.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1412 Temperature Prefer 10.0°12.8°C 995 943
Details
Acclimation temperatures had no significant affect on preferred
temperatures of juveniles (range 50°-55°F).
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1413 Temperature Prefer 12.8°C 987 943
Details
Temperature preferences were a function of age, and juvenile rainbow trout
preferred a temperature of 55° F 12 months after hatching.
Rainbow trout (Oncorhynchus mykiss)
(Larva)
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
231 Wood Fiber Limit 346 109
Details
Although wood fiber in water did not affect hatching or survival of eggs, it
did reduce growth and survival of alevins. Fingerlings maintained in water
with 250 ppm of wood fiber had instantaneous growth rates of 0.00610.0062
compared to 0.02130.0345 in the control fish.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No. 898 Idaho Phys. Assoc. Characteristic 567 555
Details
Rainbow trout fry have been found 15-30 cm deep in the gravel during the
winter.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
899 Idaho Phys. Assoc. Optimum 567 555
Details
A substrate particle size of 10-40 cm offers excellent escape and winter
cover for trout fry and smaller juveniles.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1376 Phys. Assoc. Optimum 943 -
Details
Optimal spawning gravel conditions include £5% fines. Low survival of embryos and
emerging yolksac fry result in fines ³30%.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1379 Movement Characteristic 1000 943
Details
When moving from natal gravels to rearing areas, rainbow trout fry exhibit
three distinct genetically controlled movement patterns: movement downstream
to a larger river, lake, or to the ocean; movement upstream from an outlet
river to a lake; or local dispersion within a common spawning and rearing
area to areas of low velocity and cover.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1380 Movement Characteristic 943 -
Details
Fry of lake-resident fish may either move into the lake from natal streams
during the first growing season or overwinter in the spawning stream and
move into the lake during subsequent growing seasons.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1381 Depth Prefer 1127 943
Water Motion Prefer 983
Details
Fry residing in streams prefer shallower water and slower velocities than
other life stages of stream trout.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1382 Water Motion Prefer 8 cm/s 975 943
Water Motion Tolerate <30 cm/s 983
Details
Fry utilize velocities <30 cm/sec, but prefer velocities <8 cm/sec.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1383 Area of Water Optimum 943 -
Details
A pool area of 40%-60% of the total stream area provides optimal fry habitat.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1384 Phys. Assoc. Requirement 943 -
Details
Cover in the form of aquatic vegetation, debris piles, and the interstices
between rocks is critical.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1386 Phys. Assoc. Characteristic 637 943
Water Motion Characteristic
Depth Characteristic
Details
Stream-resident trout fry usually overwinter in shallow areas of low velocity
near the stream margin, with rubble the principal cover.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1387 Phys. Assoc. Optimum 648 943
567
Details
Optimal size of substrate used as winter cover by rainbow fry and small
juveniles ranges from 10-40 cm in diameter.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1388 Temperature Prefer 13°19°C 992 943
Details
Fry preferred a temperature range 13°-19°C.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1403 Temperature Prefer 14.0°14.5°C 997 943
Details
In lab experiments, temperatures preferred by rainbow trout fry (1.1-1.8 in.
long) ranged from 56.8°-58.6°F (n=30).
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1404 Temperature Prefer 15.5°19.0°C 987 943
Details
Age was a factor in temperatures preferred (selected) by rainbow trout.
Fry selected 66.2°F at 1 month, 65.3°F at 2 months, 64.4°F at 3 months,
and 59.7°-63.7°F at 5 months.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1405 Temperature Example 986 943
Details
The growth rate of fry at 50°F was 10x greater than at 37.4°F.
Rainbow trout (Oncorhynchus mykiss)
(Non-spawning Adult)
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
173 Phys. Assoc. Tolerate 943 -
Depth Tolerate
Details
A secondclass pool is of moderate size and depth. Pool depth and size are
sufficient to provide a low-velocity resting area for a few adult trout.
From 5%-30% of the bottom is obscured because of surface turbulence, depth, or
presence of structures. Typical secondclass pools are large eddies
behind boulders and low-velocity, moderately-deep areas beneath overhanging
banks and vegetation.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
232 California Dissolved Limit - 310 109
Solids
Details
In some California lakes, growth of rainbows is correlated with
total dissolved solids, but not with food supply.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
233 Utah Depth Prefer Shallow 341 109
Details
Slow growth of rainbows compared to cutthroat trout in Bear Lake, Utah, was
associated with the rainbow's preference for shallow water.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
234 Alaska Copper Limit 339 109
Details
Slow growth in Green Lake, Alaska, was related to copper sulphate treatment and
low amounts of bottom fauna.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
240 Temperature Optimum <21°C 329 109
Temperature Limit 0°28°C
Details
The range for rainbow trout is 0°-28°C with an optimum <21°C.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
241 Utah Temperature Lethal 24°C 257 109
Calcium Lethal
Magnesium Lethal
Fluoride Lethal
Details
The lethal temperature for rainbows in Utah was 24°C (a little lower than
normal) because the water was low in calcium and magnesium. High temperatures
also increased sensitivity and mortality to fluoride concentrations.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
242 Colorado Temperature Example 19°21°C 362 109
Details
Rainbow trout were most abundant at 19°21°C in a Colorado reservoir, and
they moved downward as the summer progressed.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
243 Salinity Example 03.5% salt 412 109
Details
Rainbows were found to acclimate to a salt concentration of 03.5% salt.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
244 pH Example 5.89.5 329 109
Details
Rainbows acclimated to pH values from 5.8-9.5.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
245 Pred/Prey Characteristic 109 -
Area of Water Characteristic
Details
The food of rainbow trout in streams consists mostly of bottomliving and
terrestrial insects. Amphipods and oligochaetes are also important.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
246 California Pred/Prey Characteristic 333 109
Area of Water Characteristic
Ice Characteristic
Details
Stream rainbows feed actively all winter (even in frazil conditions) and
mostly on aquatic insects.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
247 Pred/Prey Characteristic 109 -
Area of Water Characteristic
Details
Aquatic and terrestrial insects are the primary foods of rainbow trout in
most lakes. Fish are also eaten, particularly by larger trout. Cladocera
and other plankton are a considerable part of the food in some lakes.
Amphipods are also important in many lakes.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
248 Temperature Limit 311 109
Details
Rainbow trout feed readily even when water temperatures were reduced to
the freezing point, but digestion took 23x as long at 1.6°C as at 10°C.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
290 Pred/Prey Example 298 109
Details
Fish (particularly small rainbow trout) were the principal foods of brown
trout in a Colorado reservoir.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
363 Wisconsin Pred/Prey Example 360 109
Details
Rainbow trout were more susceptible to pike predation than brown trout.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
567 Ontario Pred/Prey Example 144 110
Details
Small rainbow trout were eaten by largemouth bass shortly after trout were
stocked in an Ontario Lake.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
568 Arkansas Pred/Prey Example 185 110
Details
When rainbow trout (mostly >230 mm TL) were stocked in Lake Owachita,
Arkansas, 49% of bass >400 mm had trout in their stomachs when collected
in January and February. Ten of 11 bass >456 mm had eaten trout, but none
of 51 <400 mm had eaten trout.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
839 Area of Water Characteristic 555 -
Details
When different trout species occur in the same high-gradient river systems, they occupy
a suitable trout habitat in a longitudinally stratified manner from headwater areas
downstream. Brook or cutthroat trout occupy colder, swifter, less-fertile headwater regions;
rainbow trout occupy the midregion of the river system with intermediate habitat conditions;
and brown trout occupy the deeper, lower-velocity, warmer, more-fertile downstream regions.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
861 Idaho streams Movement Example 567 555
Temperature Example
Details
Winter hiding behavior in salmonids is triggered by low (4°-8°C) temperatures.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
870 Phys. Assoc. Limit 943 -
Depth Limit
Details
A thirdclass pool is small or shallow, or both. Pool depth and size are
sufficient to provide a low-velocity resting area for very few adult
trout. Cover (if present) is in the form of shade, surface turbulence, or
very limited structures. Typical thirdclass pools are wide, shallow pool
areas of streams or small eddies behind boulders. The entire bottom area
of the pool is visible.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1328 General 943 -
Details
Rainbows (lake or reservoir) react very differently than hatchery
rainbows recently released into a lake. Environmental stimuli associated
with survival feeding and growth show specific reactions in populations
with a history evolved over years and adopted to a particular lake.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1329 Pred/Prey Characteristic 943 -
Details
Adult and juvenile rainbow trout are opportunistic feeders and consume
a wide variety of foods.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1330 Pred/Prey Characteristic 943 -
Details
The diet of rainbow trout consists mainly of aquatic insects. Foods
(zooplankton, terrestrial insects, and fish) are locally or seasonally
important.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1331 Pred/Prey Example 950 943
Details
The relative importance of aquatic and terrestrial insects to resident
stream rainbow trout varies among different environments (seasonally,
dielly, and with the age of the trout).
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1332 Wisconsin Pred/Prey Characteristic 984 943
Details
For summer food of trout in headwater streams, 40%-50% may be composed of
terrestrial insects.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1333 Pred/Prey Example 329 943
Details
Adult stream rainbow trout occasionally consume significant quantities of
vegetation, mostly algae.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1334 British Columbia Pred/Prey Characteristic 962 943
Details
Bottom fauna may comprise 83%-94% of the winter diet of adult and juvenile
lake rainbow trout.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1349 Area of Water Example 1001 943
Phys. Assoc. Optimum
Water Motion Optimum
Details
Optimal rainbow trout riverine habitat is characterized by: clear, cold
water; a siltfree rocky substrate in rifflerun areas; an ~1:1 pooltoriffle ratio,
with areas of slow, deep water; wellvegetated stream banks; abundant instream cover;
and relatively stable water flow, temperature regimes, and stream banks.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1350 Area of Water Example 943 -
Eutrophication Optimum
Depth Optimum
Details
Optimal lacustrine habitat is characterized by clear, cold, deep lakes
that are typically oligotrophic. They may vary in size and chemical quality,
particularly in reservoir habitats. Rainbow trout are primarily stream
spawners and generally require tributary streams with gravel substrate in
riffle areas for reproduction.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1351 Phys. Assoc. Optimum 970 943
1008
Details
- Trout production is typically greatest in streams with a pooltoriffle
ratio of ~1:1.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1352 Phys. Assoc. Optimum 990 943
Water Motion Optimum
Depth Optimum
Details
Streams with deep, low-velocities pools containing extensive cover had the
most stable trout populations.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1353 Phys. Assoc. Requirement 943 -
Details
Overhead cover is preferred but not essential. Escape cover, however, must
be nearby.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1354 Phys. Assoc. Requirement 943 -
Competitors Limit
Details
The feeding stations of dominant adult trout include overhead cover when available.
The feeding stations of subdominant adults and juveniles, however, do not always include
overhead cover. Antagonistic behavior occurs at feeding stations and hierarchies are established.
However, escape cover is often shared.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1355 Depth Optimum ³15 cm 628 943
Water Motion Optimum £15 cm/s
Details
Cover for adult trout consists of areas of obscured stream bottom in water
³15 cm deep and a velocity of £15 cm/sec.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1356 Phys. Assoc. Limit - 943 -
Details
A cover area of ³25% of the total stream area provides adequate cover for
adult trout. A cover area of ³15% is adequate for juveniles.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1357 Movement Characteristic 990 943
Details
During winter, adult rainbow trout move into deeper water (first-class pools).
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1358 Idaho Movement Example 1124 943
Details
Downstream movement during or preceding winter did not occur if
sufficient winter cover was available locally.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1359 Oxygen Optimum ³7 mg/l at 943
£15°C
Details
- Optimal oxygen levels for rainbow trout are not well documented. They
appear to be ³7 mg/l at temperatures £15°C and ³9 mg/l at temperatures
>15°C.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1360 Oxygen Lethal ~3 mg/l 943 -
Details
The incipient lethal level of DO for adult and juvenile rainbow trout is
~3 mg/l or less (depending on environmental conditions, especially temperature).
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1361 Temperature Lethal >25°C, 0°C 953 943
618
Details 329
The upper and lower incipient lethal temperatures for adult rainbow are 949
25°C and 0°C, respectively. 981
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1362 Temperature Limit 23°C 981 943
Details
Zero growth rate occurred at 23°C for rainbow trout in the laboratory.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1363 Temperature Limit 25°C 943 -
Details
An upper limit of 25°C is suitable for rainbow trout (only for short periods of time).
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1364 Temperature Prefer 7°18°C 969 943
Temperature Avoid >18°C 584
Details
Adult lake rainbow trout select waters with temperatures 7°-18°C and avoid
permanent residence where temperatures are >18°C.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1365 Temperature Prefer 12.0°19.3°C 971 943
630
Details 959
Adult stream rainbow trout select temperatures 12.0°-19.3°C. 995
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1366 Temperature Optimum 15°20°C 964 943
Details
The greatest amount of rainbow trout activity occurred at 15°C and 20°C
when tested at 5°C temperature intervals.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1367 Temperature Prefer 12°19°C 943 -
Details
Stream rainbow trout select temperatures 12°-19°C.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1368 Temperature Avoid >18°C 943 -
Details
Lake resident trout avoid temperatures >18°C.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1369 Temperature Optimum 12°18°C 943 -
Details
The optimal temperature range for rainbow trout is 12°-18°C.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1370 Utah Depth Limit 584 943
Temperature Limit 18°C 980
Oxygen Limit >3 mg/l
Details
Adult lake rainbow trout remain at depths £ the 18°C isotherm and at
DO levels >3 mg/l.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1371 pH Tolerate 5.59.0 977 943
pH Optimum 6.58.0 947
Details
Most trout populations tolerate a pH range 5.5-9.0 with an optimal range 6.5-8.O.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1393 Phys. Assoc. Optimum 943 -
Depth Optimum -
Details
A firstclass pool is large and deep. Pool depth and size are sufficient
to provide a low-velocity resting area for several adult trout. Depth,
surface turbulence, or the presence of structures (logs, debris piles,
boulders, or overhanging banks and vegetation) obscure >30% of the pool
bottom. Or, the greatest pool depth is ³1.5 m in streams £5 m wide, or ³2 m
deep in streams >5 m wide.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1414 Water Motion Prefer .15.34 m/sec 943 -
Details
- Preferred fish nose velocities were 0.5-1.1 fps.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1415 Phys. Assoc. Characteristic 955 943
Details
Rainbow trout had less affinity for cover than brook or brown trout.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1416 Temperature Prefer 13.0°21.1°C 108 943
1006
Details
Preferred temperatures of rainbow trout adults are 55.4°F, 59.0°F, 61.7°F,
64.4°F, and 66°-70°F.
Rainbow trout (Oncorhynchus mykiss)
(Spawning Adult)
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
235 Finger Lakes Ice Characteristic 305 109
Light Characteristic
Temperature Characteristic
Area of Water Characteristic
Movement Characteristic
Details
In the Finger Lakes, New York, the spawning run occurs February to late May,
usually starting before ice breakup. The spawning peak is in April, with
temperatures of 5.5°13.0°C. Some females stay in the streams only five
days. Migration seems uniform night and day, but thunderstorms caused a drop
in the migration.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
236 British Columbia Ice Characteristic 364 109
Movement Characteristic
Temperature Characteristic
Light Characteristic Day
Details
In Loon Lake, British Columbia, spawners enter the outlet stream about the
same time each year despite differences in ice breakup. Spawners into inlet
streams are usually 35 weeks later and appear to be controlled by
temperature and breakup. Most migration occurs in the daytime in maximum
temperatures.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
237 California Area of Water Limit 278 109
Details
In June Lake, some spawning on shore areas was noted but there appeared
to be no survival.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
238 Area of Water Characteristic Streams 109 -
Details
Spawning is almost always in streams.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1335 Area of Water Characteristic 943 -
Details
Rainbow trout spawn almost exclusively in streams.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1336 Idaho Area of Water 1124 943
Details
Some rainbow and rainbow/cutthroat trout hybrids have successfully
reproduced in lakes without tributary streams.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1337 Oregon Area of Water Example 968 943
999
Details
Spawning in certain river systems may occur in intermittent tributary streams.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1338 (Hatchery) General 556 943
Details
Hatchery selection has resulted in fall spawning strains. Spawning of
hatchery fish may occur during almost any month of the year (depending
on the strain).
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1339 General 1009 954
985
Details
A few populations outside of the native range have modified their spawning
times to avoid adverse environmental conditions.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1342 Phys. Assoc. Prefer 975 943
996
Details
The female generally selects a redd site in gravel substrate at the head of
a riffle or downstream edge of a pool.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1345 Area of Water Characteristic 974 943
Movement Characteristic 991
Details
- Spawning takes place during the growing season in an inlet or an outlet
stream, with more than 90% of the trout returning to the stream of natal
origin.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1346 Area of Water Limit 943 -
Details
Lakes with no inlet or outlet streams usually do not possess a reproducing
population of rainbow trout.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1348 Area of Water Example 991 943
364
Details
Spawning usually begins one month earlier in an outlet than in an inlet.
The difference in time is apparently related to temperature differences.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1378 Idaho Phys. Assoc. Optimum 996 943
Details
Optimal substrate size depends on the size of the spawners, but averages
1.5-6.0 cm in diameter for rainbows <50 cm long and 1.5-10.0 cm
in diameter for spawners ³50 cm long.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1394 Depth Limit <0.2 m, 943 -
>2.5 m
Details
Depths <0.6 feet and >8.2 feet are unsuitable for spawning.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1395 British Columbia Phys. Assoc. Characteristic 978 943
Details
Gravel of particle sizes 0.04-4.00 in. in diameter were utilized for spawning
(two-thirds were 0.5-3.0 in. in diameter).
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1396 Phys. Assoc. Prefer 574 943
Details
Preferred spawning substrate consisted of particles 0.5-1.5 in. in diameter,
although particles 0.25-3.00 in. in diameter were utilized.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1397 Phys. Assoc. Optimum 943 -
Details
Substrates consisting of particle sizes ranging from silt (<0.002 in.) to
cobble (4 in.) are suitable for spawning (though not necessarily suitable
for egg incubation). The particle size range of spawning substrate selected
may be dependent on the size of the spawner.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1398 Temperature Optimum 2.8°12.8°C 574 943
Details
Temperatures 37°-55°F are desirable for spawning.
Ref. No. Locality (Stock) Factor(s) Influence(s) Data Primary Ref. No. Review No.
1399 Temperature Optimum 2.2°15.5°C 943 -
Details
Temperatures 36°-60°F are assumed suitable for spawning
(depending on locale).