As in 1948, mallards again were the mcet common breeders, comprising 
274 of the 432 identified duck broods. With the exeestion of redheads, 
cinntron teel, and American me~gansere, #11 species cefinitely incremted in 
Bbunceance over 1948 survey tetale. hater corditions probably gocount for the 
fectepee in redhead breeding ectivity. The overshaicwing 1949 influx of blue- 
winged terl decreases the relative percentage of cinnamon teal es compared 
with 1944 totale. 
Although the number of 194° broods increacea, the number of young per 
brood averaged slightly lese than in 1948. The brood pize averages of 242 
couplete waterfowl broods are classifled inte three age groups hy epecies in 
-Lole F, 
Table ©. -- Average Brood Bige - 1949 
(Incomplete broode omitted) 

1/3 grown 1/3-2/2 grown 2/3 4 erown 
Species Number Average Sige Number Average Size Numher Average Size 
Kai dard 45 6,9 ag Beat ee 6,0 
Gadwail a 9.6 Ms 9.0 1 E.d 
Pintail a 7. 1 7 aAl 4 Cee 
Gew, teal Mas 7a a a.o 3 5.9 
S-w, and Cinn, 
teal 21 Tem o 7.6 10 6.0 
Shoveler 2 6.1 Zz 6.0 
Haldpa*te 1 5.0 ] 19.0 
Wood duck B 4,4 1 4,0 
Redhead 4 o.6 E 6.1 3 6.2 
Herleazin cuck 3 4,7 
Alieylenn merganeer 
Unidentified ducks 4 246 é ape 4 FO 
Tateal and Average 94 £86 at 6.28 95 cect 
194% Averages 7 aoe A,e9 6.17 
1349 Goot Tetal and 
AVETA Cee at) 4,8 lz 4.0 3 4.6 

lhe everege number of young in troods over 2/3 grown, §.91, hae been applied 
tO ire eetimated total nucber of broode for the total production estimate. 
Tats] Summer Resident and Production Hetimatep 
Estimates of the tetal waterfowl preduction and number of eummer 
recidents were Baeed ¢n counts on 191 eample miles cf #£4 miles of potential 
creeding waterweye. Nest lost was subtracted from the number of territoriale 
to determine the potential broods of a given area, The average size of broods 
over £/3 grown was applied to the total number. of broods, observed and 
potential, for each unit. Thece average brood and reeident figures derived 
fron the samples were In turn applied te the total mileage of each unit on 
which the survey was conducted. The totel mileage of drainage ditchee end 
trrization canals wae obtained from irrigation authorities in the respective 
arene; however, in the case of irrigstion ditches the average eample was 
104, 
