134 
C. Kenneth Dodd, Jr. 
Fig. 3. Positions of tadpoles in each of the study plots as determined from photographs. 
The number of tadpoles in each quadrat is: A) N = 545, B) N = 599, C) N = 268, D) N = 213, 
E) N=480. 
As an example, had the quadrats used in this study been randomly 
preselected, the stratified random sampling method would have yielded a 
value of Y h = 180,188. The standard error rounded off to 34,000 would 
give a population estimate (with 95% confidence) between 116,200 and 
244,200 tadpoles. The literature on toads reports a wide range of eggs 
deposited per female (2000 to 20,600). Therefore, using the high figure, 6 
to 12 females produced these tadpoles; using the low figure, 58 to 122 
females produced them. Other data gathered preliminary to this study 
showed that 12 females actually bred at the pond. Assuming 100% suc- 
cessful hatch of eggs, this number was therefore within the admittedly 
large estimate predicted by tadpole numbers. On the other hand, if eggs 
