﻿22 
  REPORT 
  OF 
  COMMISSIONER 
  OF 
  FISH 
  AND 
  FISHERIES. 
  

  

  screen. 
  The 
  yolk 
  of 
  boiled 
  eggs 
  is 
  also 
  suitable, 
  but 
  it 
  is 
  comparatively 
  

   expensive 
  and 
  is 
  not 
  so 
  good 
  for 
  the 
  fish 
  as 
  liver 
  unless 
  largely 
  mixed 
  

   with 
  it. 
  

  

  As 
  the 
  fish 
  grow 
  older 
  they 
  continue 
  to 
  thrive 
  best 
  on 
  meat 
  food, 
  but 
  

   if 
  that 
  is 
  not 
  always 
  obtainable 
  in 
  sufficient 
  quantities 
  or 
  on 
  account 
  

   of 
  its 
  exj)ense, 
  a 
  very 
  good 
  substitute 
  is 
  a 
  mixture 
  of 
  shorts 
  or 
  corn 
  

   meal 
  with 
  the 
  meat. 
  This 
  is 
  prepared 
  as 
  a 
  mush 
  by 
  stirring 
  shorts 
  or 
  

   middlings 
  into 
  boihng 
  water, 
  a 
  little 
  at 
  a 
  time, 
  so 
  that 
  it 
  will 
  not 
  cook 
  

   in 
  lumps, 
  but 
  become 
  more 
  of 
  a 
  paste. 
  After 
  it 
  has 
  thoroughly 
  cooked 
  

   it 
  is 
  allowed 
  to 
  cool 
  and 
  harden. 
  The 
  best 
  proportion 
  is 
  30 
  ijounds 
  of 
  

   shorts 
  to 
  25 
  gallons 
  of 
  water 
  with 
  3 
  or 
  4 
  pounds 
  of 
  salt. 
  The 
  per- 
  

   centage 
  of 
  liver 
  to 
  be 
  used 
  in 
  this 
  mixture 
  should 
  be 
  regulated 
  by 
  the 
  

   age 
  of 
  the 
  fish, 
  feeding 
  tlie 
  very 
  young 
  fry 
  upon 
  almost 
  a 
  simple 
  meat 
  

   diet 
  and 
  increasing 
  the 
  proportion 
  of 
  mush 
  with 
  the 
  age 
  of 
  the 
  fish. 
  

  

  Doubtless 
  for 
  young 
  Salmonid^v 
  the 
  best 
  natural 
  fish 
  food, 
  not 
  arti- 
  

   ficially 
  bred, 
  is 
  the 
  roe 
  of 
  fishes 
  which 
  have 
  minute 
  ova, 
  as 
  the 
  best 
  

   food 
  for 
  the 
  mature 
  fish 
  is 
  live 
  minnows. 
  These 
  foods 
  furnish 
  the 
  fish 
  

   with 
  a 
  clean, 
  suitable 
  diet 
  and 
  leave 
  no 
  decaying 
  matter 
  on 
  the 
  bottom 
  

   of 
  the 
  troughs 
  or 
  ponds 
  to 
  foul 
  them 
  or 
  produce 
  disease. 
  But 
  these 
  

   foods 
  can 
  rarely 
  be 
  obtained 
  without 
  too 
  much 
  expense, 
  although 
  the 
  

   time 
  will 
  undoubtedly 
  come 
  when 
  perch, 
  carp, 
  and 
  similar 
  coarse 
  fish 
  

   will 
  be 
  economically 
  propagated 
  and 
  raised 
  to 
  serve 
  as 
  food 
  for 
  trout 
  

   and 
  salmon. 
  Herring 
  roe 
  is 
  now 
  canned 
  for 
  fish 
  food, 
  and 
  if 
  this 
  can 
  

   be 
  furnished 
  at 
  a 
  sufficiently 
  low 
  price 
  ic 
  may 
  ultimately 
  provide 
  an 
  

   excellent 
  food 
  for 
  young 
  salmon. 
  

  

  PLANTING 
  THE 
  FRY. 
  

  

  The 
  most 
  prominent 
  instinct 
  of 
  the 
  newly-hatched 
  salmon 
  is 
  to 
  burrow 
  

   for 
  concealment, 
  and 
  this 
  habit 
  j)ersists 
  until 
  the 
  necessity 
  for 
  active 
  

   feeding 
  compels 
  them 
  to 
  come 
  from 
  their 
  hiding-places. 
  The 
  retention 
  

   of 
  salmon 
  in 
  troughs 
  for 
  a 
  number 
  of 
  months 
  after 
  they 
  begin 
  to 
  feed 
  

   naturally 
  leads 
  to 
  a 
  considerable 
  change 
  in 
  their 
  instincts 
  and 
  makes 
  

   them 
  less 
  liable 
  to 
  escape 
  from 
  their 
  enemies 
  after 
  being 
  planted. 
  The 
  

   fry 
  are 
  liberated 
  on 
  the 
  natural 
  spawning-grounds, 
  as 
  a 
  rule, 
  as 
  soon 
  

   as 
  the 
  umbilical 
  sac 
  is 
  exhausted 
  and 
  they 
  show 
  a 
  disposition 
  to 
  feed 
  

   at 
  the 
  surfacCo 
  When, 
  for 
  any 
  reason, 
  the 
  fry 
  are 
  held 
  longer, 
  their 
  

   growth 
  varies 
  in 
  accordance 
  with 
  the 
  character 
  and 
  temperature 
  of 
  the 
  

   water 
  in 
  which 
  they 
  are 
  reared 
  and 
  the 
  food 
  they 
  receive. 
  The 
  young 
  

   fry 
  reared 
  at 
  Baird 
  station 
  grow 
  to 
  a 
  length 
  of 
  2^ 
  inches 
  from 
  the 
  time 
  

   when 
  they 
  begin 
  to 
  feed 
  in 
  February 
  until 
  the 
  middle 
  of 
  May, 
  when, 
  

   on 
  account 
  of 
  the 
  rising 
  temi^erature 
  of 
  the 
  water, 
  they 
  are 
  liberated 
  in 
  

   the 
  McCloud 
  River. 
  

  

  