by the jate? date and broods hatched after July 17 were added. Due to 
movements oF broods, some may have been counted twice. Wherever possible, 
these duplications were subtracted from the total. The final figure is 
a relatively instantaneous measure of the number of broods per square mile 
reared on the study area and in its immediate vicinity. 
A comparison of the total pairs and broods recorded indicates that on 
one square mile of this habitat 8& pairs of ducks produced 50 broods. The 
bulk of the nesting losses were in the mallard and blue-winged teal, which 
were the common nesters. 
75 
