Table 5. (continued] 



Species 



Total number known present during census period 

 Dec- July- 



Jan. April Mey Aug. 



Present in Large numbers but no count made. 



Seasonal variation in numbers of species encountered during project erea censuses 

 each month is shown in figures 1 and 2. Study data show that the number of 

 water-releted bird species (waterfowl, shorebirds, herons, gulls, ospreys, bald eagles, 

 dippers, belted kingfishers) remains relatively constant year round, with a slight 

 increase during the breeding seeson. The number of species of other birds, although 

 relatively high throughout the year, increases considerably during the breeding season. 



Census results for the dipper are shown in figure 3, and variations in average 

 monthly abundance of the most common waterfowl species, as determined by the censuses, 

 are portrayed in figure 4. Seesonal variations in duck numbers are shown in figure 5. 

 This figure shows that river sections M and N (see appendix B) are the most heavily 

 used by waterfowl, especially in April. 



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