DATA INPUTS 
n 
Number of 
Individuals f -> 
by Species^J 
T 
Estimate of Size 
of the Breeding 
Population (May) 
Fall Adult Pop ulation 
Number of 
Ponds** 
July] 
I 
Percent Ponds 
Remaining from 
May to July** 
Index to 
Number of 
Broods* 
Estimate of Non- 
Hunting Summer 
Mortality 
Estimate of 
Annual Production 
(Estimate) 
Fall Immature 
Population 
(Estimate) 
Estimate of 
-}Fall Flight of 
Birds (U.S.) 
1 
1 
Estimate of 
Adjustments to 
J 
Harvest of 
-4 
Allow for 
J 
Birds in Canada 
Fluctuation in 
Carrying Capacity 
,flf the Hahir.at 
£ 
Hunting 
Regulations 
(Aug.) 
FIGURE 3 
DETERMINING HUNTING REGULATIONS BASED UPON THE ESTIMATED 
MAGNITUDE OF THE FALL FLIGHT OF MIGRATORY WATERFOWL 
*Obtained from aerial observations and adjusted based on selected ground counts 
**Obtained from aerial observations—data potentially derived using remote 
sensing techniques 
Y = 79.26 + 1.468 X.. - 0.624X~ - 0.028X o + 0.016X, 
„ 12 3 4 
where Y = Predicted number of mallard young (millions) 
X^ = July ponds (millions) 
X^ = continental mallard breeding population (millions) 
X^ = percent of ponds remaining from May to July 
X^ = index to number of broods (thousands) unadjusted 
EXAMPLE OF A MODEL FOR PREDICTING 
ANNUAL PRODUCTION OF YOUNG MALLARDS* 
*After Geis, A.D. 
R.K. Martinson, & D.R. Anderson (1969) 
FIGURE 4