22 ILLINOIS AUDUBON BUTI ie 
invariably errors in identification of melanistic Rough-legged Hawks or for 
one of the races of Buteo borealis.” In BIRDS OF CANADA, Travener writes 
that the Swainson’s “ ... migrates to South America. It is the only hawk 
to retire entirely from the North American continent.” 
Forbush and May in AMERICAN BIRDS OF EASTERN NORTH 
AMERICA write “ ... winters in southern South America, only occasion- 
ally north of the equator.” In BIRDS OF MINNESOTA, Roberts reports 
the same winter range. Probably more significant than all of the above is 
the winter range as outlined in the A.O.U. Checklist, 5th edition, wherein 
it is stated that it winters “...in Argentina, migrates in great flocks 
through Central America, Columbia, Ecuador, and Brazil, occasionally in 
Venezuela.” The important part of this description is the omission of any 
reference to casual or accidental occurrences of the bird outside the range 
as printed. The A.O.U. Checklist consistently prints all records of casual 
and/or accidentals when a substantiating specimen is available. Evidentally 
no such specimen was available in 1957 when the 5th edition was printed. 
The popular guides by Robbins and Peterson give no indication that 
the Siwainson’s occurs in winter within the U.S. Pough states ‘a few wander 
east in the fall and some winter in extreme southern Florida.” In their 
treatment of Missouri birds, neither Widmann, nor Harris nor Bennett 
report a winter record of the Swainson’s. When Easterla and Anderson 
prepared the latest edition of the Audubon Society of Missouri’s Checklist 
of Birds of Missouri, despite diligent research, no record of this hawk in 
winter could be found. 
All of the above is written only tto emphasize that the chance of seeing 
a Swainson’s hawk in Missouri in winter is historically zero. 
An additional factor that must be considered is field marks. Probably 
the two features most generally considered in identification of the Swain- 
son’s are the coloring of the upper breast and the banded tail. Unfortu- 
nately both of these features are not uncommon in immature red-tailed 
hawks. Red-tails with dark heads and chins are common, and on many the 
dark coloration extends through the throat and spills well over onto the 
breast. When seen overhead, the similarity with a Swainson’s is at least 
superficial, and I believe every birder who twwatches hawks has, on 
occasion, been confused by this. If a banded tail is also apparent the con- 
fusion is compounded. 
The absence of any accepted records of the Swainson’s north of 
southern Florida or Texas in the winter, and the possibility of confusion 
with similarly marked redtails insures that any report of this hawk north 
of Texas or Florida will result in considerable skepticism. 
Concerning the Broad-winged, a similar set of circumstances exists. 
It’s generally accepted winter range is “only occasionally north of Central 
America.” Ludlow Griscom is quoted by Bent as follows, “The Broad- 
winged Hawk can unquestionably claim the dubious distinction of being 
the most misidentified of local hawks.” Under the heading “Winter Range” 
Bent writes, “despite many published statement to the contrary, a careful 
study of available data fails to show the Broad-winged is a regular winter 
saat anywhere in the United States.” Widmann stated, “None winter 
with us.” 
