﻿72 
  REPORT 
  OF 
  COMMISSIONER 
  OP 
  FISH 
  AND 
  FISHERIES. 
  

  

  In 
  tlie 
  extensive 
  section 
  of 
  the 
  West 
  in 
  which 
  the 
  fish 
  abounds 
  its 
  

   name 
  varies 
  in 
  different 
  localities; 
  "red 
  sides," 
  "mountain 
  trout," 
  

   "brook 
  trout," 
  and 
  "golden 
  trout," 
  besides 
  "rainbow 
  trout," 
  are 
  some 
  

   of 
  the 
  popular 
  appellations, 
  while 
  in 
  the 
  States 
  east 
  of 
  the 
  Mississippi 
  

   Eiver 
  it 
  is 
  generally 
  called 
  "rainbow 
  trout" 
  or 
  "California 
  trout." 
  

  

  TEANSPLANTING. 
  

  

  The 
  rainbow 
  trout 
  has 
  been 
  successfully 
  transplanted 
  in 
  many 
  of 
  the 
  

   mountain 
  streams 
  in 
  different 
  parts 
  of 
  the 
  United 
  States, 
  where 
  it 
  

   grows 
  and 
  multiplies 
  rapidly, 
  as 
  is 
  shown 
  by 
  the 
  many 
  favorable 
  

   reports. 
  The 
  best 
  results, 
  however, 
  seem 
  to 
  have 
  been 
  obtained 
  from 
  

   plants 
  made 
  in 
  streams 
  of 
  Michigan, 
  Missouri, 
  Arkansas, 
  throughout 
  

   the 
  Alleghany 
  Mountain 
  ranges, 
  and 
  in 
  Colorado, 
  Nevada, 
  and 
  other 
  

   Western 
  States. 
  It 
  was 
  introduced 
  into 
  eastern 
  waters 
  by 
  the 
  United 
  

   States 
  Fish 
  Commission 
  in 
  1880, 
  but 
  it 
  is 
  i)ossible 
  that 
  specimens 
  of 
  it, 
  

   or 
  its 
  spawn, 
  had 
  been 
  brought 
  east 
  prior 
  to 
  that 
  time 
  by 
  some 
  of 
  the 
  

   State 
  commissions 
  or 
  by 
  private 
  enterprise. 
  

  

  It 
  is 
  believed 
  that 
  this 
  species 
  will 
  serve 
  for 
  stocking 
  streams 
  for- 
  

   merly 
  inhabited 
  by 
  the 
  brook 
  trout 
  {Salvelinus 
  fontinalis), 
  in 
  which 
  the 
  

   latter 
  no 
  longer 
  thrives, 
  owing 
  to 
  the 
  clearing 
  of 
  the 
  lands 
  at 
  the 
  

   sources 
  of 
  the 
  streams, 
  which 
  has 
  produced 
  changed 
  conditions 
  in 
  and 
  

   along 
  the 
  waters 
  not 
  agreeable 
  to 
  the 
  brook 
  trout's 
  wild 
  nature. 
  The 
  

   rainbow 
  is 
  adapted 
  to 
  warmer 
  and 
  deeper 
  waters, 
  and 
  is 
  therefore 
  

   suited 
  to 
  many 
  of 
  the 
  now 
  depleted 
  streams 
  which 
  flow 
  from 
  the 
  moun- 
  

   tains 
  through 
  the 
  cultivated 
  lands 
  of 
  the 
  valleys. 
  

  

  Rainbow 
  trout 
  differ 
  widely 
  from 
  brook 
  trout 
  and 
  other 
  pugnacious 
  

   fishes, 
  in 
  that 
  they 
  feed 
  principa/Iy 
  upon 
  worms, 
  larvae, 
  Crustacea, 
  and 
  

   the 
  like, 
  and 
  do 
  not 
  take 
  readily 
  to 
  minnows 
  as 
  food. 
  They 
  should 
  be 
  

   planted 
  in 
  spring 
  or 
  early 
  summer, 
  when 
  their 
  natural 
  food 
  is 
  abun- 
  

   dant, 
  as 
  they 
  will 
  then 
  grow 
  more 
  rapidly 
  and 
  become 
  accustomed 
  to 
  

   life 
  in 
  the 
  stream; 
  and 
  when 
  wor.ms, 
  larvae, 
  etc., 
  are 
  no 
  longer 
  to 
  be 
  

   found, 
  their 
  experience 
  and 
  size 
  will 
  enable 
  them 
  to 
  take 
  a 
  minnow 
  or 
  

   anything 
  that 
  may 
  present 
  itself 
  in 
  the 
  shape 
  of 
  food. 
  

  

  In 
  the 
  Eastern 
  States 
  fry 
  should 
  not 
  be 
  planted 
  in 
  open 
  waters 
  until 
  

   they 
  are 
  several 
  months 
  old, 
  and 
  then 
  not 
  until 
  the 
  temperature 
  of 
  the 
  

   streams 
  begins 
  to 
  rise; 
  but 
  fish 
  hatched 
  in 
  December 
  and 
  January 
  can 
  

   safely 
  be 
  planted 
  in 
  April 
  and 
  May. 
  On 
  the 
  Pacific 
  slope 
  the 
  fry 
  may 
  

   be 
  successfully 
  liberated 
  at 
  any 
  time 
  after 
  the 
  umbilical 
  sac 
  is 
  absorbed. 
  

  

  SIZE 
  AND 
  GROWTH. 
  

  

  The 
  size 
  of 
  the 
  rainbow 
  trout 
  depends 
  upon 
  its 
  surroundings, 
  the 
  

   volume 
  and 
  temperature 
  of 
  the 
  water, 
  and 
  the 
  amount 
  of 
  food 
  it 
  con- 
  

   tains. 
  The 
  average 
  weight 
  of 
  those 
  caught 
  from 
  streams 
  in 
  the 
  East 
  is 
  

   probably 
  less 
  than 
  a 
  pound, 
  but 
  some 
  weighing 
  63 
  pounds 
  have 
  been 
  

   taken. 
  In 
  the 
  Ozark 
  region 
  of 
  "Missouri 
  they 
  are 
  caught 
  weighing 
  5 
  to 
  

   10 
  pounds. 
  In 
  some 
  of 
  the 
  cold 
  mountain 
  streams 
  of 
  Colorado 
  their 
  

   average 
  weight 
  is 
  not 
  more 
  than 
  (J 
  or 
  8 
  ounces, 
  but 
  in 
  lakes 
  in 
  the 
  

  

  