4 BULLETIN 936, U. S. DEPARTMENT OF AGRICULTURE. 



gadwall, ruddy duck, pintail, and green-winged teal. The widgeon 

 and blue-winged teal are only tolerably common, and the canvas- 

 back, a species that is decidedly rare in summer, is included on the 

 authority of A. O. Treganza, of Salt Lake City; one additional 

 species, the lesser scaup duck, is probably casual in its nesting here. 

 On June 12. the writer, with his assistant, T. E. Griesa, found a male 

 of this species near Long Point on North Bay. Thislurd passed and 

 repassed a dozen times or more, circling about as ducks do when their 

 nests are approached. Other scaup ducks were seen during the entire 

 summer, but these birds remained in the open bays below the marshy 

 areas and it was certain that they were nonbreeding individuals. 

 It is a common thing for a few ducks of this species to pass the 

 summer in regions far south of their breeding range, but in the 

 instance mentioned there is little question that the male seen was a 

 breeding bird. 



In the enumeration of the breeding ducks of this area the entire 

 region described under the general account of the Bear River marshes 

 was covered as carefully as practicable between May 15 and June 26. 

 Dependence was placed only in part upon birds seen in open water ; 

 each channel was traversed by boat or on foot, and extensive marsh 

 areas were tramped in search for nests (PI. II, fig. 1) or nesting birds. 

 In some cases favorable localities were covered two or three times in 

 order to check the results obtained. Ducks continue to breed until 

 a much later date, but these delayed birds are probably those whose 

 first nests have in some way been destroyed. Cinnamon teals only 

 four or five days old were seen August 8, and redheads less than a 

 third grown were common as late as September 7 ; a large number of 

 young redheads were unable to fly until after September 25. An 

 attempt to continue a count of the breeding clucks in this region after 

 July 1, however would fail entirely to give an adequate conception of 

 the number present earlier in the season/ 



The figures given in tabulating the final results of the counts are 

 approximate ; the enumerations were conservative, and it is believed 

 that the results are sufficiently accurate, allowance being made for 

 not more than 40 per cent of error. Greater accuracy can hardly be 

 claimed in work of this sort except on small areas covered minutely. 

 Ducks are adept at hiding, especially where vegetation is heavy, and 

 often allow persons to pass within a few feet without flushing. Thus 

 the examination of marsh areas through glasses from a distance is 

 unsatisfactory, as many birds readily pass unnoticed. The results of 

 the enumeration of breeding birds are given in the following table, 

 the species being arranged in the order of their abundance : 



