﻿VII 
  

  

  we 
  find, 
  by 
  turning 
  to 
  the 
  ttible 
  ol' 
  the 
  yieJd 
  on 
  tlie 
  Sus- 
  

   quehanna, 
  that 
  the 
  ininimimi 
  catch 
  for 
  that 
  river 
  occur- 
  

   red 
  the 
  same 
  year. 
  The 
  increase 
  in 
  the 
  Susquehanna 
  for 
  

   1880, 
  however, 
  was 
  as 
  nuirked 
  as 
  that 
  in 
  the 
  Potomac 
  ; 
  

   thereby 
  clearly 
  indicating 
  such 
  increase 
  as 
  being 
  the 
  

   resiilt 
  of 
  the 
  deposit 
  of 
  the 
  artili(dally 
  produced 
  fisli 
  in 
  

   both 
  these 
  streams. 
  

  

  The 
  diagram 
  will 
  further 
  show 
  that 
  1870 
  — 
  the 
  tirst 
  

   year 
  in 
  Avhich 
  it 
  is 
  possible 
  to 
  compare 
  the 
  yield 
  of 
  the 
  

   two 
  localities— 
  was 
  comparatively 
  a 
  good 
  year 
  for 
  the 
  

   Potomac 
  fisheries 
  and 
  a 
  had 
  one 
  for 
  those 
  of 
  the 
  Susque- 
  

   hanna. 
  The 
  next 
  year 
  (1871) 
  showed 
  a 
  decrease 
  in 
  the 
  

   Potomac, 
  with 
  a 
  corresponding 
  increase 
  in 
  the 
  Susque- 
  

   hanna. 
  The 
  following 
  year^l872— 
  the 
  <'atch 
  in 
  the 
  

   Susquehanna 
  increased 
  only 
  8,000 
  and 
  that 
  of 
  the 
  

   Potomac 
  96,810. 
  

  

  We 
  next 
  find 
  the 
  year 
  1873 
  to 
  have 
  ])een 
  one 
  of 
  great 
  

   abundance 
  in 
  the 
  Potomac, 
  and 
  of 
  great 
  scarcity 
  in 
  the 
  

   Susquehanna. 
  In 
  1874 
  tlie 
  Potomac 
  decreased 
  from 
  

   1,142,(329 
  to 
  958.977: 
  while 
  the 
  Susquehanna 
  increased 
  

   from 
  516,000 
  to 
  583,000. 
  

  

  We 
  recognize 
  in 
  these 
  statements 
  tlie 
  inevitable 
  result 
  

   of 
  successive 
  years 
  of 
  over-hshing 
  ; 
  of 
  disturbing 
  the 
  fish 
  

   on 
  their 
  spawning 
  beds 
  ; 
  and 
  of 
  preventing 
  them, 
  alto- 
  

   gether, 
  from 
  reaching 
  such 
  beds. 
  Tlie 
  diagTam 
  indicates 
  

   a 
  continued, 
  though 
  somewhat 
  irregular, 
  downward 
  

   tendency 
  in 
  the 
  yiehl 
  of 
  the 
  Potomac 
  fi-om 
  1873 
  to 
  1878 
  : 
  

   and 
  of 
  the 
  Susquehanna 
  from 
  1872 
  to 
  1877, 
  the 
  loss 
  in 
  

   bf)th 
  rivers 
  being 
  finally 
  arrested 
  by 
  the 
  same 
  means. 
  

  

  It 
  will 
  be 
  remembered 
  that 
  the 
  work 
  of 
  shad 
  hatching 
  

   was 
  commenced 
  in 
  1875, 
  and 
  was 
  continued 
  the 
  following 
  

   year 
  — 
  ])rincipally 
  at 
  the 
  head 
  of 
  the 
  Bay. 
  In 
  1876 
  and 
  

  

  1877 
  large 
  numbers 
  of 
  young 
  fish 
  were 
  released 
  ; 
  and 
  in 
  

  

  1878 
  a 
  slight 
  inci-ease 
  of 
  shad 
  was 
  observed 
  in 
  the 
  waters 
  

   of 
  the 
  Bay 
  — 
  a 
  remarkable 
  feature 
  of 
  this 
  increase 
  being 
  

   the 
  prejionderance 
  of 
  small 
  male 
  fish. 
  In 
  1876 
  our 
  ope- 
  

   rations 
  at 
  the 
  head 
  of 
  the 
  Bay 
  wei'e 
  not 
  prosecuted 
  on 
  a 
  

  

  