BIRDS OF THE PAP AGO SAGUARO NATIONAL MONUMENT. 53 



birds were seen. Near the head of the Salt River branch of the lake 

 cormorants were seen in about the same number as on Tonto River. 

 I did not examine any nests here, but in all probability the two colonies 

 are of about the same size. 



During the nesting season the cormorants appeared to remain close 

 to the nests, none being seen during June at the lower end of the 

 lake. A month later, during the first week in July, several were 

 observed in the vicinity of the dam. 



At the present time conditions are certainly favorable to the cor- 

 morants, and the colony will probably increase in numbers from year 

 to year. Nesting on a Federal bird reservation, they are secure of 

 injury from man, their nests are safe from ordinary danger, and in 

 the lake there is abundance of food. The dead trees serving for 

 their present nesting sites, however, are certain to disappear in the 

 course of time, and the cormorants will then have a problem to 

 solve. 



Besides those seen at Roosevelt Lake, cormorants were noted near 

 Tempe on May 31. First a flock of 29 birds was seen, flying in 

 V-shaped formation, like wild geese, and headed straight up the Salt 

 River. A little later six birds appeared, circling about over the 

 river bottom, flying low above the willows. 



PALLID GREAT BLUE HERON. 

 Ardea hcrodias tregansai Court. 



Recognition marks. Size large; length about 4 feet. Relatively 

 small body and short tail, with long legs, neck, and bill, and broad, 

 widespreading wings. Flight slow and laborious. The live bird 

 generally appears bluish or grayish in color. Sometimes the streak- 

 ings on the breast can be seen, but as a rule the birds can not be 

 approached near enough for their markings to be distinguished. 

 Known to most people under the name of " blue crane." 



Occurrence. Herons existed along the rivers before Roosevelt 

 Lake was in existence, but the coming of this body of water has 

 unquestionably resulted in a considerable increase in their numbers. 

 At the present time the great blue heron forms a pleasing and pictur- 

 esque feature of the lake, whether perched on some rocky point or 

 flapping slowly over the water, for the birds are present in numbers. 



The herons were nesting below the mouth of Tonto River, in com- 

 pany with the Farallon cormorants. In one dead tree top on June 8 

 there were 10 nests, mostly occupied by young great blue herons, 

 while nearby others were scattered, one, two, or three in a tree. 

 The parent birds were wary, as usual, most of them taking flight 

 when our boat was still some distance away. From several of the 

 nests young birds departed on what were evidently their first flights. 



