Table IV. - Aerial Census of Waterfowl Production -- Oak-Chestnut Stratum 
Size in Size in Size of Size of 
Sq. Mi. Linear Sample Sample Ducks Observed Ducks Observed Production 
Type Year si Miles** Sq. Mi. Linear in sample /sq. or L. Mile Index 
. LS mn lr 
(1) Mi. (2) Broods Pairs Broods Pairs Broods Pairs 
Transect 1951 5,379 - 22.0 - 0 0 0 0 0 0 
1952 (3) 5,379 - 22.0 - 6 0 0.27 0 1,452 0 
1953 5,379 - 23.0 - 11 5 0.48 0.22 2,582 1,183 
Rivers 1951 - 408 - 138 4 2 0.03 0.015 12 6 
1952 (3) - 408 - 138 2 1 0.015 0.01 6 4 
1953 - 408 - 147 4 5 0.03 0.034 12 14 
Swamps 1951 1.4 - 0.2 ~ 1 0 5.00 0 7 0 
1952 (3) 1.4 - 0.2 - ] 0 5.00 0 7 0 
1953 6.0 - 0.4 - 0 3 0 7.50 0 45 
Marshes 1951 6.4 - 1.4 - 5 0 3.57 0 23 0 
1952 (3) 6.4 - 1.4 - 0 l 0 0.71 0 5 
1953 7.7 - Le 3 - l 1 0.77 0.77 6 6 
Estuarial 1951 40.0 - a 8 - 8 2 2.86 0.71 114 28 
Marsh 1952 (3) 40.0 - 2.8 - 1 6 0. 36 2.14 14 86 
1953 30.4 - 2.8 - 0 4 0 1,43 0 43 
Ocean 1951 32.0 - 2.8 - 3 3 1.07 1.07 34 34 
Marsh 1952 (3) 32.0 - 2.8 ~- 0 4 0 1,43 0 46 
1953 29.9 - 2.8 - 0 2 0 0.71 0 21 
ee 
* Includes only transects, swamps and marshes, 
** Includes only shoreline of all major lakes and rivers. 
(1) Includes only random samples of transect area, swamps and marshes to give 
+ 30 percent error. 
(2) Includes only random samples of shoreline of major lakes 
+ 20 percent error for rivers; recommended minimum for lakes. 
(3) Figures for the July 2 to 14 flights only; also flown in 1952 on July 22-28. 
and rivers to give 
L22 
