﻿OYSTERS 
  AND 
  METHODS 
  OF 
  OYSTER-CULTURE. 
  285 
  

  

  fiilly 
  set. 
  Currents, 
  even 
  of 
  considerable 
  strength, 
  do 
  not 
  prevent 
  the 
  

   settling 
  down 
  of 
  the 
  larval 
  oyster 
  and 
  its 
  fixation 
  upon 
  a 
  proper 
  

   surface. 
  

  

  In 
  the 
  preparation 
  of 
  this 
  surface 
  the 
  currents 
  are 
  also 
  eftective, 
  

   inasmuch 
  as 
  by 
  their 
  scouring 
  action 
  they 
  prevent 
  the 
  deposit 
  of 
  sedi- 
  

   ment 
  and 
  slime, 
  which 
  soon 
  render 
  collectors 
  unsuitable 
  for 
  the 
  fixation 
  

   of 
  the 
  young 
  oyster. 
  Finally, 
  where 
  the 
  fry 
  are 
  uniformly 
  distributed 
  

   in 
  a 
  body 
  of 
  Avater 
  a 
  collector 
  placed 
  in 
  a 
  current 
  will 
  collect 
  more 
  spat 
  

   than 
  one 
  in 
  quiet 
  water, 
  because 
  a 
  greater 
  quantity 
  of 
  water 
  and 
  con- 
  

   sequently 
  a 
  larger 
  number 
  of 
  fry 
  will 
  be 
  brought 
  into 
  contact 
  with 
  it. 
  

   Points 
  around 
  which 
  fry-charged 
  water 
  sweejjs 
  with 
  sufiflcieut 
  velocity 
  

   to 
  prevent 
  the 
  deposit 
  of 
  sediment 
  are 
  good 
  places 
  for 
  the 
  location 
  of 
  

   collectors. 
  

  

  Freshets, 
  for 
  several 
  reasons, 
  usually 
  have 
  a 
  bad 
  effect 
  upon 
  the 
  

   oyster-beds. 
  When 
  the 
  volume 
  of 
  fresh 
  water 
  is 
  large, 
  the 
  oysters 
  

   suffer 
  from 
  the 
  decrease 
  in 
  the 
  density. 
  Large 
  quantities 
  of 
  mud 
  and 
  

   sediment 
  are 
  brought 
  down 
  by 
  the 
  floods 
  and 
  often 
  deposited 
  on 
  the 
  

   beds, 
  covering 
  up 
  the 
  cultch 
  and 
  smothering 
  the 
  young 
  spat, 
  and, 
  if 
  

   the 
  amount 
  of 
  sedimentation 
  is 
  very 
  great, 
  even 
  injuring 
  or 
  killing 
  

   the 
  adults. 
  

  

  DEPTH 
  OF 
  WATER. 
  

  

  The 
  vertical 
  range 
  of 
  the 
  cultivated 
  oyster 
  beds 
  is 
  from 
  the 
  shore 
  

   line 
  to 
  a 
  depth 
  of 
  15 
  fathoms. 
  In 
  New 
  Jersey, 
  Chesapeake 
  Bay, 
  South 
  

   Carolina, 
  and 
  other 
  places, 
  there 
  are 
  beds 
  which 
  are 
  partially 
  exposed 
  

   at 
  low 
  water, 
  while 
  in 
  Long 
  Island 
  Sound 
  successful 
  oyster-culture 
  

   is 
  carried 
  on 
  in 
  depths 
  as 
  great 
  as 
  15 
  fathoms, 
  the 
  average 
  over 
  planted 
  

   grounds 
  in 
  that 
  region, 
  however, 
  being 
  from 
  5 
  to 
  6 
  fathoms. 
  In 
  most 
  

   places, 
  however, 
  the 
  planting 
  is 
  done 
  in 
  shallow 
  bays 
  and 
  coves. 
  

  

  WEATHER 
  CONDITIONS 
  — 
  STORMS, 
  OALES, 
  AND 
  ICE, 
  

  

  Gales 
  rarely 
  have 
  any 
  influence 
  upon 
  adult 
  oysters 
  in 
  deep 
  water, 
  

   but 
  they 
  sometimes 
  seriously 
  aftect 
  shallow-water 
  beds. 
  Heavy 
  surf 
  

   occasionally 
  carries 
  away 
  the 
  oysters 
  and 
  throws 
  them 
  upon 
  the 
  beach, 
  

   or 
  they 
  may 
  be 
  buried 
  in 
  situ 
  by 
  the 
  sand 
  and 
  seaweeds 
  which 
  the 
  

   waves 
  lodge 
  upon 
  the 
  beds. 
  Sometimes, 
  after 
  the 
  lapse 
  of 
  a 
  short 
  time, 
  

   the 
  beds 
  are 
  again 
  uncovered 
  by 
  the 
  eroding 
  ett'ects 
  of 
  currents, 
  but 
  in 
  

   many 
  cases 
  they 
  are 
  practically 
  destroyed, 
  both 
  old 
  and 
  young 
  being 
  

   smothered 
  by 
  the 
  overlying 
  deposits. 
  

  

  In 
  winter, 
  ice 
  often 
  grounds 
  upon 
  the 
  beds 
  during 
  gales 
  and 
  does 
  

   considerable 
  damage. 
  The 
  oyster 
  appears 
  also 
  to 
  be 
  temporarily 
  

   affected 
  by 
  the 
  mere 
  freezing 
  of 
  the 
  waters, 
  and 
  it 
  is 
  said 
  that, 
  in 
  the 
  

   Chesapeake, 
  oysters 
  on 
  the 
  deeper 
  beds 
  are 
  more 
  aflPected 
  than 
  those 
  in 
  

   shoiil 
  and 
  brackish 
  water, 
  becoming 
  dark, 
  slimy, 
  and 
  worthless 
  for 
  the 
  

   market. 
  Ten 
  days 
  or 
  a 
  fortnight 
  must 
  elapse 
  after 
  the 
  disappearance 
  

   of 
  the 
  ice 
  before 
  they 
  become 
  again 
  fit 
  for 
  use. 
  

  

  The 
  fry 
  are 
  more 
  affected 
  by 
  the 
  weather 
  than 
  are 
  the 
  adults. 
  Dr. 
  

   Kyder 
  found 
  that 
  in 
  the 
  swimming 
  stage 
  they 
  were 
  killed 
  by 
  thunder- 
  

  

  