﻿DISTRIBUTION. 
  15 
  

  

  Lawrence, 
  thence 
  almost 
  due 
  north 
  for 
  2,000 
  miles 
  to 
  its 
  breeding- 
  

   grounds, 
  but 
  it 
  is 
  practically 
  unknown 
  in 
  the 
  interior 
  of 
  Canada. 
  In 
  

   the 
  fall 
  many 
  thousands 
  migrate 
  along 
  the 
  west 
  shore 
  of 
  Hudson 
  Bay 
  

   and 
  from 
  its 
  southern 
  borders 
  cross 
  to 
  the 
  Atlantic 
  coast. 
  Thus 
  the 
  

   migration 
  route 
  is 
  in 
  the 
  form 
  of 
  an 
  ellipse 
  some 
  3,000 
  miles 
  long 
  

   north 
  and 
  south 
  by 
  1,000 
  miles 
  wide. 
  

  

  Probably 
  in 
  no 
  other 
  region 
  in 
  the 
  world 
  do 
  so 
  large 
  a 
  proportion 
  

   of 
  the 
  birds 
  migrate 
  approximately 
  north 
  and 
  south 
  as 
  in 
  North 
  

   America 
  north 
  of 
  the 
  Gulf 
  of 
  Mexico. 
  The 
  outlines 
  of 
  the 
  coast, 
  the 
  

   courses 
  of 
  the 
  large 
  rivers, 
  and 
  the 
  trend 
  of 
  the 
  mountain 
  chains 
  unite 
  

   to 
  make 
  northward 
  and 
  southward 
  migration 
  easy 
  and 
  natural. 
  In 
  the 
  

   case 
  of 
  ducks, 
  however, 
  there 
  is 
  a 
  factor 
  that 
  causes 
  thousands 
  of 
  

   individuals 
  of 
  several 
  species 
  to 
  take 
  a 
  northwest-and-southeast 
  route. 
  

   The 
  Atlantic 
  coast 
  from 
  Chesapeake 
  Bay 
  to 
  South 
  Carolina 
  is 
  especially 
  

   favorable 
  as 
  a 
  winter 
  home 
  for 
  ducks 
  and 
  until 
  recent 
  years 
  countless 
  

   flocks 
  swarmed 
  throughout 
  this 
  district. 
  Such 
  other 
  birds 
  as 
  winter 
  in 
  

   this 
  region 
  breed 
  principally 
  in 
  New 
  England 
  and 
  northward 
  along 
  the 
  

   Atlantic 
  slope 
  to 
  Labrador. 
  But 
  northeastern 
  North 
  America 
  east 
  of 
  

   Hudson 
  Bay 
  harbors 
  only 
  a 
  small 
  number 
  of 
  ducks 
  in 
  summer. 
  

   They 
  prefer 
  the 
  marshes, 
  lakes, 
  and 
  streams 
  of 
  the 
  districts 
  west 
  of 
  

   Hudson 
  Bay, 
  and 
  the 
  great 
  bulk 
  of 
  North 
  American 
  ducks 
  breed 
  there. 
  

   Thus 
  there 
  are 
  two 
  great 
  districts, 
  one 
  suitable 
  for 
  a 
  summer 
  home 
  

   and 
  the 
  other 
  for 
  winter, 
  and 
  the 
  migration 
  route 
  between 
  them 
  is 
  

   nearly 
  northwest 
  and 
  southeast, 
  between 
  Chesapeake 
  Bay 
  and 
  Great 
  

   Slave 
  Lake. 
  Through 
  much 
  of 
  the 
  intervening 
  2,000 
  miles 
  is 
  a 
  suc- 
  

   cession 
  of 
  lakes, 
  large 
  and 
  small, 
  that 
  find 
  no 
  counterpart 
  elsewhere 
  

   on 
  this 
  hemisphere, 
  and 
  which 
  furnish 
  ideal 
  conditions 
  for 
  ducks, 
  

   both 
  as 
  regards 
  food 
  and 
  shelter. 
  

  

  Among 
  the 
  most 
  conspicuous 
  species 
  that 
  follow 
  this 
  migration 
  

   route 
  are 
  the 
  redhead, 
  canvasback, 
  and 
  greater 
  scaup. 
  Less 
  abun- 
  

   dant, 
  though 
  still 
  numerous, 
  are 
  the 
  baldpate, 
  pintail, 
  and 
  lesser 
  scaup, 
  

   while 
  the 
  route 
  is 
  extensively 
  used 
  also 
  by 
  the 
  mallard, 
  gadwall, 
  

   shoveler, 
  and 
  ring-necked 
  duck. 
  Nearly 
  all 
  the 
  individuals 
  of 
  these 
  

   10 
  species 
  that 
  winter 
  along 
  the 
  Atlantic 
  coast 
  reach 
  their 
  winter 
  home 
  

   by 
  a 
  pronounced 
  southeastward 
  migration, 
  though 
  it 
  must 
  be 
  under- 
  

   stood 
  that 
  these 
  individuals 
  constitute 
  only 
  a 
  small 
  percentage 
  of 
  the 
  

   vast 
  army 
  of 
  these 
  same 
  species 
  that 
  breed 
  in 
  central 
  Canada. 
  

  

  One 
  of 
  the 
  principal 
  winter 
  homes 
  of 
  North 
  American 
  ducks 
  and 
  

   geese 
  is 
  the 
  State 
  of 
  California, 
  where 
  congregates 
  during 
  this 
  season 
  

   the 
  larger 
  part 
  of 
  all 
  the 
  individuals 
  that 
  breed 
  west 
  of 
  the 
  Rocky 
  

   Mountains. 
  

  

  DISTRIBUTION. 
  

  

  The 
  family 
  of 
  ducks, 
  geese, 
  and 
  swans 
  is 
  represented 
  in 
  North 
  

   America 
  by 
  63 
  species 
  and 
  8 
  subspecies 
  — 
  a 
  total 
  of 
  71 
  recognized 
  

   4510— 
  No. 
  26—06 
  2 
  

  

  