Net 
Table 56.—~-Method of Comparing Relative Size of Two Migratory Bird Populations 
I. Manitoba and Saskatchewan Populations of Mallards 
Col (1) and (2) represent breeding-season recoveries (i.e., May to July inclusive) of birds banded 
Columns (3) and (4) are taken directly from a sample 
of 194 adult mallards banded in Manitoba; columns (5) and (6) show part of a sample of 99 adults 
in Illinois and the other reference areas, 
similarly banded in Saskatchewan. 
mostly in the 1930's; all the others represent the period 1939-6, 
Column 
Area 
of 
Reference 
Missouri 
Ark -~La e 
Kansas 
Oklahoma 
SubtctalL 
I ois 
Total 

(1) (2) 
Reference Birds 
Recovered in oud 
Man. ask. S 
9 7 led 
ly 17 0.8 
c 20 0.3 
10 12 0.8 
30 b6 0.7 
c... ao. . ot 
9 . 
II. Alberta and Saskatchewan Populations of Mallards 
The Alberta-banded birds (columns 3 and ) are taken from a sample of 30 recoveries. 
ty (3) (uy) (5) (8 (ey 
Recovere n 
Reference Areas 4 
Man. Sask. 
Oe O. 
It #S.7 20  £44.0 1b 
29 1h.9 88 17.6 0.8 
2 1.0 17 30h 0.3 
3 Le 17 3k 0.4 
19 oes} 30 6.0 1.6 
katchewan-—banded birds are part of a sample of 99, 
Column 
Area 
of 
Reference 
Kansas 
Oklahoma 
Tllinois 
Missouri 
Ark.—-La. 
ro) 
(1) 
1 2 
Reference Birds 
Recovered in 5 

e ask. 
22 20 1.1 
8 12 0.7 
19 43 Ow 
h 9 0.) 
7 17 0.) 
<5 ae 0 Ca 0 Py oa 
( 
(3) (hb). ©) (6) 
Recovered in al 
Reference Areas via 
Alta. oask. __gt 
No. q Noe 54 
10 2.9 «<7 3.4 0.9 
3 0.9 17 3.4 0.3 
6 1.8 30 6.0 0.3 
6 1.8 20 .0 0.4 
18 5.3 88 17.6 0.3 
The Missouri birds were banded in the 1920's; the Kansas birds 
Manitoba | 
Population 
Equals 
The Sas- 
1). 
Alberta 
Population 
