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  REPORT 
  OF 
  COMMISSIONER 
  OF 
  FISH 
  AND 
  FISHERIES. 
  

  

  Owing 
  to 
  the 
  fact 
  that 
  the 
  fish 
  appear 
  to 
  spawn 
  mostly 
  at 
  night, 
  

   when 
  the 
  pound 
  nets 
  are 
  lifted 
  in 
  the 
  morning 
  the 
  ripe 
  eggs 
  have 
  in 
  

   many 
  cases 
  been 
  extruded 
  before 
  the 
  spawn-taker 
  could 
  secure 
  them. 
  

   The 
  injuries 
  which 
  the 
  fish 
  sustain 
  while 
  iu 
  the 
  pound 
  nets 
  and 
  during 
  

   the 
  hauling 
  of 
  the 
  nets 
  appear 
  to 
  seriously 
  afiect 
  the 
  eggs 
  and 
  cause 
  

   the 
  non-hatching 
  of 
  a 
  comparatively 
  large 
  percentage. 
  Undoubtedly 
  

   better 
  results 
  maybe 
  obtained 
  if 
  a 
  number 
  of 
  nets 
  are 
  fished 
  exclu- 
  

   sively 
  for 
  this 
  purpose, 
  insuring 
  the 
  careful 
  removal 
  of 
  fish 
  at 
  the 
  best 
  

   times 
  for 
  taking 
  and 
  fertilizing 
  the 
  eggs. 
  

  

  The 
  eggs 
  are 
  very 
  delicate 
  and 
  susceptible 
  to 
  meteorological 
  influ- 
  

   ences. 
  Their 
  development 
  is 
  markedly 
  affected 
  by 
  water 
  temperature 
  

   and 
  atmospheric 
  conditions; 
  electrical 
  disturbances, 
  as 
  with 
  other 
  fish 
  

   eggs, 
  are 
  injurious, 
  but 
  to 
  what 
  extent 
  and 
  in 
  what 
  way 
  are 
  not 
  known. 
  

   The 
  largest 
  number 
  of 
  ripe 
  eggs 
  thus 
  far 
  taken 
  from 
  a 
  single 
  specimen 
  

   is 
  00,000, 
  but 
  the 
  average 
  is 
  only 
  20,000. 
  

  

  The 
  Chester 
  jar, 
  such 
  as 
  is 
  used 
  in 
  hatching 
  flatfish 
  eggs, 
  has 
  been 
  

   found 
  the 
  best 
  apparatus 
  for 
  Spanish 
  mackerel 
  eggs. 
  If 
  the 
  jars 
  are 
  

   kept 
  clean 
  and 
  not 
  overcrowded, 
  a 
  constant 
  current 
  of 
  water 
  does 
  not 
  

   seem 
  to 
  be 
  essential; 
  of 
  a 
  lot 
  of 
  C0,000 
  eggs 
  in 
  a 
  jar 
  of 
  quiet 
  water, 
  90 
  

   per 
  cent 
  hatched. 
  The 
  cod 
  tidal 
  box 
  is 
  also 
  adapted 
  to 
  this 
  work. 
  

  

  In 
  ordinary 
  bay 
  water 
  having 
  a 
  density 
  of 
  1.014 
  to 
  1.019, 
  the 
  eggs 
  

   are 
  buoyant 
  and 
  remain 
  at 
  the 
  surface 
  until 
  hatching 
  ensues; 
  but 
  in 
  

   water 
  of 
  low 
  specific 
  gravity 
  they 
  sink 
  and 
  give 
  unsatisfactory 
  results. 
  

   The 
  period 
  of 
  incubation 
  is 
  very 
  short. 
  Under 
  normal 
  conditions 
  eggs 
  

   hatch 
  iu 
  20 
  to 
  30 
  hours, 
  averaging 
  25 
  hours, 
  at 
  a 
  temperature 
  of 
  77° 
  

   or 
  78°. 
  The 
  fry 
  are 
  planted 
  soon 
  after 
  hatching. 
  

  

  HADDOCK, 
  POLLOCK, 
  AND 
  OTHER 
  GADIBJE. 
  

  

  The 
  methods 
  of 
  culture 
  employed 
  with 
  the 
  cod 
  are 
  applicable 
  to 
  other 
  

   members 
  of 
  the 
  cod 
  family 
  having 
  buoyant 
  eggs. 
  The 
  United 
  States 
  

   Fish 
  Commission 
  have 
  frequently 
  taken 
  and 
  hatched 
  eggs 
  of 
  the 
  pollock 
  

   [Follachius 
  virens) 
  and 
  the 
  haddock 
  [Melanogrammus 
  ceglijinus). 
  Both 
  

   are 
  important 
  food-fishes, 
  but 
  much 
  less 
  valuable 
  than 
  the 
  cod, 
  and 
  the 
  

   collection 
  of 
  eggs 
  has 
  generally 
  been 
  only 
  supplemental 
  to 
  cod 
  work. 
  

  

  The 
  pollock 
  is 
  found 
  from 
  New 
  Jersey 
  northward. 
  It 
  goes 
  iu 
  large 
  

   schools, 
  which 
  are 
  often 
  found 
  at 
  the 
  surface, 
  thus 
  dififeriug 
  from 
  the 
  

   cod 
  and 
  haddock. 
  The 
  average 
  weight 
  is 
  9 
  or 
  10 
  pounds, 
  and 
  the 
  

   maximum 
  about 
  30 
  pounds. 
  Fishing 
  is 
  chiefly 
  done 
  from 
  small 
  vessels 
  

   and 
  boats, 
  and 
  is 
  most 
  important 
  iu 
  Massachusetts. 
  The 
  value 
  of 
  the 
  

   annual 
  catch 
  is 
  about 
  $100,000. 
  The 
  pollock 
  is 
  an 
  excellent 
  food-fish 
  

   in 
  both 
  a 
  fresh 
  and 
  a 
  salted 
  condition. 
  

  

  The 
  eggs 
  of 
  the 
  pollock 
  have 
  at 
  times 
  been 
  gathered 
  in 
  large 
  num- 
  

   bers 
  in 
  the 
  vicinity 
  of 
  Gloucester; 
  during 
  some 
  seasons 
  about 
  40,000,000 
  

   eggs 
  have 
  been 
  taken. 
  The 
  eggs 
  measure 
  about 
  z^^ 
  inch 
  in 
  diameter. 
  

   The 
  pollock 
  spawning 
  season 
  includes 
  the 
  months 
  of 
  October, 
  Novem- 
  

   ber, 
  and 
  December. 
  The 
  fish 
  from 
  which 
  eggs 
  are 
  obtained 
  are 
  taken 
  

  

  