24 | THE CONDOR Vol. XXIV 
Economically these birds may have some detrimental habits in tending to destroy 
fish planted in the lake. But the majority of the fish captured by them are the slow- 
moving German carp (Cyprinus carpio) and a few blue-gills (Hupomis pallidus), the 
principal game and food fish of the lake, the large-mouth black bass (Micropterus sal- 
moides), probably being disturbed but little. Of three fish seen dropped by cormorants 
at the nesting colonies two were carp and one was a blue-gill. 
Chaulelasmus streperus (Linnaeus). Gadwall. About a dozen Gadwalls were 
found at the Tonto end of the lake, where they were most frequently seen among the 
partly submerged brush or on the mud banks. The two specimens collected showed no 
signs of breeding activity either in habits or anatomically. 
Spatula clypeata (Linnaeus). Shoveller. There appeared to be about ten Shov- 
ellers inhabiting the mud flats and brush at the Tonto end of the lake. The female 
taken had small undeveloped ovaries. 
Fig. 18. NEST AND YOUNG OF PALLID GREAT BLUE HERON. TONTO END OF ROOSE- 
VELT LAKE, ARIZONA, 
Erismatura jamaicensis (Gmelin). Ruddy Duck. Ruddy Ducks were found only 
at the Tonto end of the lake where there were probably about twenty individuals.. Three 
females which were collected each had small, undeveloped ovaries. 
Ardea herodias treganzai Court. Pallid Great Blue Heron. The colonies of Great 
Blue Herons were somewhat scattered, being mostly at the Tonto end of the lake where 
about eighty pairs were nesting. Practically every nest examined contained young, 
which in most cases were nearly ready to leave. About forty pairs were found nesting 
at the Salt River end of the lake, May 26, making a total of about 120 pairs on the lake. 
Herodias egretta (Gmelin). Egret. Two birds of this species, apparently a pair, 
were seen on several occasions cn the mud flats at the mouth of Tonto Creek. At one 
time, after crawling for many yards through spiny desert vegetation, I succeeded in 
i. “4 
i 
Ae F 
