﻿MANUAL 
  OF 
  FISH-CULTURE. 
  131 
  

  

  In 
  the 
  following 
  season 
  the 
  fry 
  were 
  placed 
  in 
  pens 
  in 
  a 
  pond. 
  Conferva> 
  formed 
  

   in 
  the 
  ponds, 
  clogging 
  tho 
  screens, 
  and 
  the 
  water 
  got 
  so 
  warm 
  that 
  the 
  fry, 
  which 
  

   were 
  dying 
  rapidly, 
  were 
  placed 
  in 
  the 
  pond 
  with 
  the 
  large 
  fish. 
  

  

  In 
  11^93 
  the 
  experiments 
  were 
  more 
  encouraging. 
  About 
  120,000 
  fry 
  wore 
  placed 
  in 
  

   a 
  new 
  pond, 
  200 
  feet 
  scjuare 
  and 
  from 
  2\ 
  to 
  14 
  feet 
  deep, 
  supplied 
  with 
  25 
  gallons 
  of 
  

   rnnuing 
  water 
  per 
  minute 
  at 
  the 
  lowest 
  stage. 
  Fifty 
  thousand 
  fry 
  were 
  held 
  in 
  a 
  

   small 
  tank 
  at 
  the 
  hatchery, 
  so 
  that 
  their 
  habits, 
  food, 
  etc., 
  could 
  be 
  studied. 
  This 
  

   afforded 
  more 
  instruction 
  than 
  all 
  former 
  experiments 
  combined. 
  Before 
  the 
  umbili- 
  

   cal 
  sac 
  was 
  absorbed 
  the 
  fry 
  began 
  to 
  take 
  the 
  prepared 
  food, 
  and 
  as 
  soon 
  as 
  the 
  sac 
  

   was 
  entirely 
  gone 
  they 
  ate 
  freely. 
  They 
  grew 
  rapidly 
  and 
  did 
  well 
  until 
  the 
  middle 
  

   of 
  May, 
  when, 
  the 
  weather 
  being 
  very 
  warm, 
  the 
  temperature 
  of 
  the 
  tank 
  rose 
  to 
  

   63° 
  F., 
  resulting 
  in 
  the 
  death 
  of 
  some 
  of 
  the 
  fry 
  and 
  necessitating 
  a 
  removal 
  of 
  the 
  

   remaining 
  fry 
  to 
  the 
  pond 
  containing 
  the 
  other 
  fry 
  of 
  the 
  same 
  age. 
  These 
  fry 
  were 
  

   from 
  1 
  to 
  IJ 
  inches 
  long 
  when 
  put 
  in 
  the 
  pond. 
  They 
  had 
  been 
  fed 
  on 
  nothing 
  but 
  

   very 
  finely 
  divided 
  glutin, 
  a 
  product 
  of 
  wheat, 
  of 
  a 
  yellowish-Avhite 
  color, 
  very 
  even 
  

   in 
  size 
  and 
  semi-lntoyant. 
  The 
  Hoating 
  projierty 
  of 
  this 
  food 
  is 
  supposed 
  to 
  be 
  very 
  

   important, 
  as 
  the 
  whitefish 
  when 
  young 
  do 
  not 
  feed 
  on 
  the 
  bottom, 
  which 
  is 
  their 
  

   habit 
  when 
  older. 
  Any 
  part 
  of 
  this 
  food 
  which 
  settles 
  on 
  the 
  bottom 
  must 
  be 
  removed, 
  

   as 
  it 
  is 
  liable 
  to 
  ferment 
  and 
  rise 
  to 
  the 
  surface, 
  when, 
  if 
  the 
  fry 
  eat 
  it, 
  they 
  will 
  die. 
  

  

  For 
  the 
  purpose 
  of 
  removing 
  the 
  fry 
  to 
  another 
  pond 
  the 
  large 
  pond 
  was 
  drawn 
  in 
  

   November 
  of 
  the 
  same 
  year 
  in 
  which 
  they 
  were 
  hatched. 
  A 
  large 
  seine 
  was 
  com- 
  

   l)letely 
  filled 
  with 
  fish 
  at 
  the 
  first 
  haul. 
  Being 
  very 
  delicate, 
  a 
  great 
  many 
  were 
  

   killed 
  before 
  efforts 
  could 
  be 
  made 
  to 
  move 
  them. 
  It 
  is 
  estimated 
  that 
  nearly 
  50,000 
  

   of 
  these 
  young 
  whitefish 
  were 
  lost. 
  They 
  were 
  from 
  7 
  to 
  9 
  inches 
  long, 
  being 
  about 
  

   8 
  months 
  old. 
  Several 
  thousand 
  were 
  saved 
  which 
  are 
  now 
  (1895) 
  2+ 
  years 
  old. 
  

   When 
  2 
  years 
  old 
  70 
  were 
  caught, 
  which 
  measured 
  from 
  16 
  to 
  18 
  inches 
  long. 
  

  

  When 
  the 
  fry 
  are 
  about 
  an 
  inch 
  long 
  they 
  are 
  fed 
  on 
  a 
  stiff 
  dough 
  made 
  of 
  fine 
  

   middlings. 
  This 
  food 
  is 
  placed 
  on 
  the 
  bottom 
  of 
  the 
  tank 
  and 
  all 
  that 
  is 
  not 
  

   consumed 
  is 
  removed. 
  This 
  is 
  also 
  the 
  sole 
  food 
  of 
  the 
  adult 
  whitefish. 
  It 
  is 
  

   placed 
  in 
  water 
  shallow 
  enough 
  so 
  that 
  tho 
  fish-culturist 
  may 
  see 
  if 
  it 
  is 
  all 
  consumed 
  

   during 
  the 
  night, 
  the 
  fish 
  feeding 
  exclusively 
  at 
  that 
  time. 
  If 
  all 
  is 
  not 
  eaten, 
  a 
  

   less 
  (]uantity 
  is 
  given 
  for 
  the 
  next 
  day, 
  as 
  a 
  matter 
  of 
  economy 
  and 
  to 
  prevent 
  the 
  

   pollution 
  of 
  the 
  water. 
  

  

  It 
  has 
  been 
  found 
  that 
  in 
  the 
  raising 
  of 
  fry 
  the 
  temperature 
  of 
  the 
  water 
  should 
  

   not 
  go 
  above 
  55^ 
  F., 
  and 
  that 
  65° 
  is 
  fatal, 
  while 
  fish 
  three 
  or 
  four 
  months 
  old 
  will 
  

   stand 
  a 
  much 
  higher 
  temperature. 
  

  

  