﻿90 
  OTTEE-TRAWL 
  FISHERY. 
  

  

  fore, 
  that 
  there 
  is 
  strong 
  evidence 
  of 
  a 
  depletion 
  of 
  the 
  plaice 
  and 
  

   some 
  evidence 
  of 
  a 
  falling 
  off 
  in 
  the 
  haddock, 
  the 
  two 
  most 
  distinctly 
  

   trawl-caught 
  fish. 
  

  

  SUMMARY 
  AND 
  CONCLUSIONS. 
  

  

  1. 
  Otter 
  trawls 
  do 
  not 
  destroy 
  the 
  spawn 
  of 
  the 
  commercially 
  im- 
  

   portant 
  demersal 
  fishes, 
  all 
  of 
  which 
  have 
  pelagic 
  or 
  floating 
  eggs. 
  

  

  2. 
  Otter 
  trawls 
  do 
  not 
  seriously 
  disturb 
  the 
  bottom 
  over 
  which 
  

   they 
  are 
  fished 
  nor 
  materially 
  denude 
  it 
  of 
  the 
  organisms 
  which 
  di- 
  

   rectly 
  and 
  indirectly 
  serve 
  as 
  food 
  for 
  commercial 
  fishes. 
  

  

  3. 
  The 
  investigations 
  conducted 
  by 
  the 
  Bureau 
  of 
  Fisheries 
  indi- 
  

   cated 
  that 
  during 
  1913 
  trawling 
  interfered 
  but 
  little 
  with 
  line 
  fish- 
  

   ing 
  and 
  caused 
  practically 
  no 
  damage 
  to 
  the 
  trawl 
  lines. 
  From 
  the 
  

   nature 
  of 
  the 
  two 
  fisheries, 
  however, 
  it 
  is 
  believed 
  both 
  can 
  not 
  be 
  

   extensively 
  conducted 
  on 
  the 
  same 
  grounds 
  without 
  resultant 
  acci- 
  

   dental 
  damage 
  to 
  or 
  interference 
  with 
  the 
  lines, 
  especially 
  in 
  foggy 
  

   weather. 
  

  

  4. 
  Otter 
  trawls 
  as 
  compared 
  with 
  lines 
  take 
  a 
  much 
  larger 
  propor- 
  

   tion 
  of 
  commercial 
  fishes 
  too 
  small 
  to 
  market. 
  From 
  January 
  to 
  

   May 
  3 
  per 
  cent 
  of 
  the 
  cod 
  and 
  11 
  per 
  cent 
  of 
  the 
  haddock, 
  and 
  from 
  

   June 
  to 
  December 
  40 
  per 
  cent 
  of 
  the 
  cod 
  and 
  38 
  per 
  cent 
  of 
  the 
  had- 
  

   dock 
  were 
  unmarketably 
  small, 
  while 
  the 
  lines 
  caught 
  practically 
  no 
  

   such 
  fish. 
  These 
  proportions 
  were 
  fully 
  maintained 
  in 
  the 
  respective 
  

   classes 
  of 
  vessels 
  fishing 
  at 
  the 
  same 
  season 
  on 
  the 
  same 
  grounds. 
  

   These 
  young 
  fish 
  are 
  practically 
  all 
  destroyed. 
  

  

  5. 
  Otter 
  trawls 
  as 
  compared 
  with 
  trawl 
  lines 
  market 
  a 
  much 
  larger 
  

   proportion 
  of 
  small 
  fish, 
  and, 
  therefore, 
  they 
  not 
  only 
  destroy 
  more 
  

   small 
  fish 
  not 
  utilized, 
  but 
  are 
  biologically 
  more 
  wasteful, 
  by 
  reason 
  

   of 
  the 
  smaller 
  size 
  of 
  the 
  marketable 
  fish. 
  As, 
  however, 
  a 
  large 
  pro- 
  

   portion 
  of 
  these 
  smaller 
  fish 
  would 
  undoubtedly 
  die 
  or 
  be 
  destroyed 
  

   under 
  natural 
  conditions 
  before 
  reaching 
  the 
  large 
  or 
  medium 
  size, 
  

   the 
  effects 
  on 
  the 
  total 
  supply 
  of 
  fish 
  are 
  less 
  to 
  a 
  conceivable, 
  but 
  at 
  

   present 
  indeterminable, 
  degree 
  than 
  the 
  data 
  presented 
  would 
  

   indicate. 
  

  

  6. 
  Practically 
  the 
  only 
  food 
  fish 
  which 
  the 
  otter 
  trawl 
  has 
  added 
  

   to 
  the 
  present 
  yield 
  of 
  the 
  fisheries 
  on 
  the 
  banks 
  is 
  the 
  " 
  sole," 
  of 
  

   which 
  about 
  600,000 
  pounds 
  were 
  caught 
  in 
  1913. 
  This 
  is 
  equal 
  to 
  

   about 
  three 
  times 
  the 
  quantity 
  of 
  hake, 
  36 
  per 
  cent 
  of 
  the 
  cod, 
  and 
  

   5 
  per 
  cent 
  of 
  the 
  haddock, 
  or 
  about 
  4 
  per 
  cent 
  of 
  the 
  three 
  combined 
  

   marketed 
  by 
  the 
  trawlers. 
  On 
  the 
  other 
  hand, 
  it 
  is 
  estimated 
  that 
  

   this 
  is 
  less 
  than 
  one-third 
  of 
  the 
  weight 
  of 
  the 
  immature 
  cod, 
  had- 
  

   dock, 
  and 
  hake 
  destroyed 
  by 
  otter 
  trawls. 
  The 
  trawlers 
  have 
  not 
  

   added 
  greatly 
  to 
  the 
  food 
  supply 
  by 
  the 
  introduction 
  of 
  fishes 
  not 
  

   previously 
  taken 
  in 
  quantities 
  by 
  the 
  liners. 
  They 
  may 
  have 
  con- 
  

   ferred 
  some 
  benefit 
  on 
  the 
  consumer 
  by 
  catching 
  and 
  marketing 
  

  

  