﻿MANUAL 
  OF 
  FISH-CULTURE. 
  187 
  

  

  water 
  rivers 
  is 
  wholly 
  for 
  the 
  purpose 
  of 
  spawning-. 
  The 
  time 
  of 
  their 
  

   arrival 
  in 
  a 
  given 
  place 
  is 
  quite 
  constant 
  from 
  year 
  to 
  year. 
  The 
  

   branch 
  alewife 
  precedes 
  the 
  summer 
  alewife 
  by 
  three 
  or 
  four 
  weeks, 
  

   and 
  also 
  arrives 
  several 
  weeks 
  before 
  the 
  .shad. 
  The 
  run 
  of 
  the 
  glut 
  

   herring 
  occurs 
  during 
  the 
  middle 
  of 
  the 
  shad 
  season. 
  The 
  branch 
  

   herring 
  ascends 
  the 
  small 
  streams 
  to 
  spawn, 
  often 
  entering 
  branches 
  

   only 
  10 
  feet 
  wide 
  and 
  not 
  more 
  than 
  G 
  inches 
  deep. 
  After 
  spawning, 
  

   very 
  little 
  is 
  known 
  of 
  the 
  habits 
  of 
  the 
  fish 
  or 
  of 
  the 
  departure 
  from 
  

   the 
  rivers; 
  nor 
  has 
  their 
  winter 
  abode 
  been 
  ascertained. 
  

  

  The 
  eggs 
  resemble 
  those 
  of 
  the 
  sea 
  herring 
  rather 
  than 
  of 
  the 
  shad, 
  

   being 
  glutinous 
  and 
  adhering 
  to 
  brush, 
  stones, 
  piling, 
  and 
  other 
  

   objects 
  under 
  water. 
  The 
  netting, 
  ropes, 
  and 
  stakes 
  of 
  traps 
  in 
  which 
  

   the 
  fish 
  are 
  caught 
  are 
  often 
  covered 
  with 
  the 
  fertilized 
  eggs; 
  the 
  ale- 
  

   wives 
  thus 
  have 
  a 
  great 
  advantage 
  over 
  the 
  shad, 
  and 
  to 
  this 
  fact 
  

   must 
  largely 
  be 
  attributed 
  the 
  continuance 
  of 
  the 
  supply 
  in 
  the 
  face 
  of 
  

   very 
  extensive 
  fishing 
  not 
  counteracted 
  by 
  artificial 
  propagation. 
  The 
  

   eggs 
  are 
  about 
  o^r 
  inch 
  in 
  diameter. 
  

  

  There 
  has 
  been 
  no 
  effort 
  to 
  regularly 
  hatch 
  the 
  eggs 
  of 
  alewives 
  

   artificially. 
  The 
  undiminished 
  abundance 
  of 
  these 
  fish 
  in 
  the 
  regions 
  

   of 
  the 
  most 
  extensive 
  fisheries 
  has 
  made 
  their 
  artificial 
  propagation 
  

   unnecessary. 
  In 
  the 
  New 
  England 
  States, 
  where 
  the 
  alewife 
  is 
  an 
  

   important 
  fish 
  in 
  many 
  of 
  the 
  smaller 
  towns, 
  the 
  supply 
  has 
  been 
  

   maintained 
  by 
  constructing 
  fishways 
  which 
  permit 
  the 
  fish 
  to 
  reach 
  

   their 
  spawning- 
  grounds. 
  In 
  this 
  way 
  comparatively 
  small 
  streams 
  have 
  

   annually 
  yielded 
  very 
  large 
  quantities 
  of 
  fish, 
  and 
  many 
  streams, 
  in 
  

   which 
  the 
  alewife 
  run 
  had 
  been 
  entirely 
  inhibited 
  by 
  obstructions, 
  have 
  

   been 
  reopened 
  and 
  very 
  successfully 
  restocked. 
  

  

  As 
  early 
  as 
  1871 
  the 
  eggs 
  of 
  the 
  alewife 
  were 
  artificially 
  fertilized 
  

   and 
  hatched, 
  and 
  those 
  of 
  the 
  branch 
  herring 
  were 
  similarly 
  treated 
  in 
  

   1877. 
  Their 
  cultivation 
  presents 
  no 
  special 
  difficulties, 
  and 
  can 
  be 
  

   prosecuted 
  on 
  a 
  large 
  scale 
  whenever 
  it 
  becomes 
  necessary. 
  The 
  milt 
  

   is 
  first 
  taken 
  in 
  a 
  pan, 
  and 
  then, 
  while 
  one 
  person 
  keeps 
  the 
  pan 
  in 
  

   motion, 
  another 
  expresses 
  the 
  eggs; 
  this 
  prevents 
  the 
  eggs 
  from 
  mat- 
  

   ting 
  together 
  and 
  facilitates 
  the 
  contact 
  of 
  all 
  with 
  the 
  milt. 
  Eggs 
  

   adhering 
  to 
  the 
  side 
  of 
  the 
  pan 
  may 
  be 
  removed 
  with 
  a 
  stream 
  of 
  water. 
  

  

  The 
  automatic 
  shad 
  jar 
  is 
  the 
  proper 
  apparatus 
  in 
  which 
  to 
  hatch 
  the 
  

   eggs, 
  which 
  are 
  treated 
  precisely 
  like 
  those 
  of 
  the 
  shad. 
  Sufficient 
  

   water 
  is 
  supplied 
  to 
  keep 
  them 
  moving 
  freely 
  and 
  to 
  overcome 
  adhesion. 
  

  

  The 
  alewives 
  are 
  much 
  more 
  prolific 
  than 
  either 
  the 
  shad 
  or 
  the 
  sea 
  

   herring. 
  On 
  one 
  occasion, 
  in 
  the 
  Potomac 
  Eiver, 
  04:4: 
  female 
  branch 
  

   herring 
  yielded 
  06,206,000 
  eggs, 
  an 
  average 
  of 
  102,800 
  per 
  fish. 
  Prob- 
  

   ably 
  100,000 
  may 
  be 
  taken 
  as 
  a 
  fair 
  average. 
  The 
  eggs 
  hatch 
  quite 
  

   quickly 
  under 
  normal 
  conditions. 
  The 
  period 
  of 
  incubation, 
  in 
  water 
  

   having 
  a 
  mean 
  temperature 
  of 
  60° 
  F., 
  is 
  6 
  days. 
  The 
  fry 
  are 
  very 
  

   minute. 
  They 
  are 
  planted 
  at 
  the 
  same 
  time 
  and 
  in 
  the 
  same 
  manner 
  

   as 
  shad 
  fry. 
  Those 
  in 
  the 
  rivers 
  and 
  lakes 
  attain 
  a 
  length 
  of 
  2 
  to 
  3 
  

   inches 
  by 
  the 
  time 
  they 
  move 
  toward 
  salt 
  water 
  in 
  the 
  fall. 
  

  

  