﻿258 
  REPOET 
  OF 
  COMMISSIONER 
  OF 
  FISH 
  AND 
  FISHERIES. 
  

  

  beds 
  which 
  rej^ularly 
  produce 
  oj'sters 
  marketable 
  as 
  '^selects" 
  are 
  

   limited 
  to 
  the 
  upper 
  parts 
  of 
  the 
  rivers. 
  These 
  03'sters 
  will 
  live 
  in 
  

   pure 
  sea 
  water, 
  and 
  are 
  not 
  immediately 
  killed 
  by 
  water 
  which 
  is 
  

   almost 
  fresh, 
  but 
  they 
  thrive 
  best 
  in 
  water 
  which 
  has 
  a 
  specific 
  gravity 
  

   of 
  about 
  1.014:.« 
  

  

  During 
  a 
  season 
  of 
  very 
  great 
  drought, 
  however, 
  the 
  water 
  over 
  

   the 
  beds 
  in 
  the 
  upper 
  parts 
  of 
  North 
  liiver 
  becomes 
  more 
  dense 
  than 
  

   at 
  the 
  mouth 
  or 
  at 
  Beaufort 
  Inlet, 
  this 
  peculiar 
  condition 
  being 
  

   brought 
  about 
  by 
  evaporation. 
  The 
  water 
  in 
  the 
  upper 
  part 
  of 
  the 
  

   river 
  is 
  ^^ery 
  shallow, 
  but 
  is 
  spread 
  out 
  over 
  a 
  large 
  area. 
  Before 
  it 
  

   is 
  carried 
  past 
  the 
  river's 
  mouth 
  the 
  tide 
  changes, 
  and, 
  since 
  there 
  is 
  

   no 
  fresh- 
  water 
  supply, 
  the 
  same 
  water 
  is 
  returned, 
  day 
  by 
  daj' 
  grow- 
  

   ing 
  more 
  salt. 
  In 
  August, 
  1900, 
  when 
  a 
  density 
  of 
  1.023 
  was 
  noted 
  

   at 
  Beaufort 
  Inlet, 
  a 
  density 
  of 
  1.02-18 
  was 
  noted 
  at 
  the 
  station 
  near 
  

   the 
  Sunken 
  Kock 
  beds. 
  It 
  is 
  also 
  quite 
  common 
  after 
  heavy 
  winds 
  

   from 
  the 
  northeast 
  and 
  east 
  to 
  find 
  the 
  water 
  at 
  the 
  mouth 
  of 
  this 
  

   river 
  less 
  dense 
  than 
  over 
  the 
  oyster 
  beds 
  farther 
  up, 
  brackish 
  water 
  

   having 
  been 
  l^lown 
  down 
  through 
  Core 
  Sound 
  from 
  Pamlico. 
  This 
  

   occurred 
  on 
  November 
  28, 
  1899, 
  the 
  densit}' 
  at 
  the 
  river's 
  mouth 
  

   being 
  1.0112, 
  while 
  over 
  the 
  planted 
  area 
  (station 
  7) 
  it 
  was 
  1.0162, 
  

  

  In 
  summer 
  the 
  temperature 
  of 
  the 
  water 
  becomes 
  very 
  high, 
  espe- 
  

   cially 
  on 
  days 
  when 
  low 
  water 
  occurs 
  near 
  midda}^, 
  93° 
  F. 
  having 
  

   been 
  noted 
  above 
  Harlow 
  Creek 
  in 
  Newport, 
  and 
  on 
  the 
  experimental 
  

   bed 
  in 
  North 
  River 
  at 
  such 
  times. 
  In 
  winter 
  ice 
  often 
  forms 
  over 
  the 
  

   beds, 
  killing 
  the 
  03^sters 
  which 
  arc 
  exposed 
  or 
  which 
  are 
  in 
  very 
  

   shallow 
  water. 
  

  

  From 
  tide 
  gauges 
  located 
  at 
  the 
  Morehead 
  City 
  railroad 
  wharf 
  and 
  

   at 
  Lenoxville 
  during 
  the 
  survey, 
  and 
  later 
  from 
  the 
  gauge 
  at 
  the 
  Fish 
  

   Commission 
  laboratory 
  at 
  Beaufort, 
  the 
  average 
  daily 
  vertical 
  range 
  

   of 
  the 
  tides 
  in 
  the 
  harbor 
  was 
  found 
  to 
  be 
  about 
  3.5 
  feet, 
  with 
  a 
  maxi- 
  

   mum 
  height 
  of 
  5.2 
  feet. 
  High 
  winds 
  modify 
  to 
  a 
  considerable 
  

   extent 
  the 
  height 
  of 
  the 
  tides 
  and 
  to 
  less 
  degree 
  their 
  regularity, 
  but 
  

   usually 
  the 
  periods 
  of 
  ebb 
  and 
  flow 
  take 
  place 
  with 
  mathematical 
  

   regularity, 
  five 
  hours 
  flood 
  being 
  followed 
  by 
  seven 
  hours 
  ebb. 
  The 
  

   stages 
  of 
  the 
  tides 
  on 
  the 
  natural 
  03"ster 
  grounds, 
  which, 
  in 
  both 
  

   rivers, 
  are 
  located 
  about 
  8 
  nautical 
  miles 
  from 
  the 
  jetties 
  at 
  Fort 
  

   Macon, 
  have 
  been 
  found 
  to 
  occur 
  two 
  and 
  one-fourth 
  hours 
  later 
  than 
  

   the 
  corresponding 
  stages 
  at 
  the 
  latter 
  places. 
  

  

  As 
  was 
  mentioned 
  above, 
  lines 
  can 
  be 
  dra\\'n 
  in 
  both 
  rivers 
  separating 
  

   with 
  a 
  fair 
  degree 
  of 
  accuracy 
  the 
  beds 
  that 
  produce 
  a 
  good 
  quality 
  of 
  

   03'sters 
  from 
  those 
  that 
  do 
  not. 
  In 
  Newport 
  River 
  such 
  a 
  line 
  would 
  

   reach 
  from 
  a 
  point 
  just 
  below 
  the 
  mouth 
  of 
  Harlow 
  Creek 
  to 
  the 
  03"ster 
  

   signal 
  "Willis" 
  on 
  the 
  opposite 
  shore. 
  In 
  North 
  River 
  it 
  would 
  con- 
  

   nect 
  a 
  point 
  half 
  wa3'^ 
  between 
  the 
  mouth 
  of 
  the 
  small 
  creek 
  below 
  

  

  a 
  Fresh 
  water 
  has 
  a 
  specific 
  gravity 
  of 
  1.000; 
  that 
  of 
  sea 
  water 
  is 
  about 
  1.025. 
  

  

  