PLUMAGE CHARACTERS 
The tail feathers, the primary feathers of the wing, 
and the feathers of the breast and belly are all use- 
ful in determining age in Canada geese. 
Tail Feathers—The frayed or notched tip in the 
tail feathers of immature waterfowl, first shown to 
be a character of age by Beebe & Crandall (1914) 
and later described by Schigler (1924) and others, 
has been widely employed by waterfowl biologists 
(Elder 1946:98; 
most instances, the tail 
as a criterion of age Hanson 
1949:179), Fig. 2. In 
feathers of the first postnatal plumage may be readily 
differentiated from those of the adult plumage by 
Fig. 2 Tail feathers of Canada geese: 
notched tip is evident in most of the feathers of the immatures 
D 
{ and B, immatures in winter; C 
their narrower, more tapered outline and their less in- 
tense pigmentation. During the winter, the tail feath- 
ers of the immature plumage are gradually replaced 
by the longer, broader, and more deeply pigmented 
tail feathers characteristic of adult plumage. The tail 
feathers are generally replaced two at a time, begin- 
ning with the central pair. In immature Canada geese 
in southern Illinois, replacement of tail feathers in 
winter is largely limited to the central two or three 
pairs. Observations made in early May, 1959, on the 
breeding grounds of these geese in northern Ontario, 
revealed that the tail feather criterion of age could be 
employed, with nearly comparable accuracy, during 
adult in winter; D, immature in early May. A 
