﻿26 
  REPORT 
  OP 
  COMMISSIONER 
  OF 
  FISH 
  AND 
  FISHERIES. 
  

  

  percentage 
  of 
  loss 
  can 
  not 
  be 
  given 
  ; 
  but 
  the 
  total 
  loss 
  of 
  alevins 
  at 
  

   the 
  hatchery 
  the 
  past 
  season 
  was 
  32,934, 
  or 
  0.3 
  per 
  cent, 
  in 
  a 
  total 
  of 
  

   10,000,000. 
  The 
  loss 
  after 
  feeding 
  began 
  was 
  very 
  slight, 
  amounting 
  

   only 
  to 
  5,710. 
  

  

  Tlie 
  alevins 
  and 
  the 
  fry 
  of 
  the 
  Pacific 
  salmon 
  jDossess 
  great 
  vitality 
  

   and 
  are 
  less 
  liable 
  to 
  disease 
  than 
  those 
  of 
  any 
  of 
  the 
  other 
  Salmonidcv. 
  

  

  The 
  natural 
  conditions 
  for 
  hatching, 
  rearing, 
  and 
  planting 
  fry 
  at 
  the 
  

   Sisson 
  hatchery 
  are 
  excellent; 
  the 
  water 
  supply 
  is 
  unlimited 
  and 
  is 
  

   very 
  free 
  from 
  sediment, 
  even 
  during 
  stormy 
  weather, 
  while 
  it 
  has 
  an 
  

   equable 
  temj)erature, 
  averaging 
  52° 
  for 
  the 
  year, 
  seldom 
  falling 
  to 
  40° 
  

   or 
  exceeding 
  60°. 
  

  

  No 
  part 
  of 
  the 
  hatching-house 
  work 
  requires 
  more 
  attention 
  or 
  is 
  of 
  

   such 
  vital 
  importance 
  as 
  the 
  cleaning 
  of 
  the 
  troughs. 
  Up 
  to 
  the 
  time 
  

   that 
  the 
  alevins 
  begin 
  to 
  feed 
  the 
  troughs 
  should 
  be 
  thoroughly 
  cleaned 
  

   once 
  every 
  day 
  by 
  rubbing 
  them 
  down 
  with 
  the 
  hand 
  covered 
  with 
  a 
  

   coarse 
  crash 
  mitten, 
  and 
  after 
  they 
  begin 
  feeding 
  the 
  troughs 
  require 
  

   much 
  more 
  attention. 
  One 
  hour 
  after 
  each, 
  meal 
  the 
  troughs 
  should 
  

   be 
  cleaned 
  by 
  passing 
  a 
  bunch 
  of 
  stiff 
  feathers 
  over 
  the 
  sides 
  and 
  

   bottom, 
  first 
  removing 
  the 
  division 
  and 
  harbor 
  plates 
  and 
  the 
  plug 
  at 
  

   the 
  foot 
  of 
  the 
  trough. 
  

  

  