220 HERONS AND BITTERNS 



Generally speaking, Herons are gregarious, nesting and roosting in 

 flocks. While feeding they are more solitary, but each night they 

 regularly return to roost with their kind in a ' 'rookery." Bitterns do 

 not associate in flocks, and are generally found singly or in pairs. As a 

 rule, they feed in grassy marshes, while Herons more commonly resort 

 to the shores of lakes, rivers, bays, or salt-water lagoons. Herons perch, 

 and usually nest in trees; Bitterns rarely or never do. Some species 

 secure their food of frogs, fish, small reptiles, etc., by standing rigidly 

 motionless and waiting for it to come within striking distance, or by 

 wading for it with the utmost caution. Others run rapidly and noisily 

 through the water, trusting to their agility and the rapidity of their 

 spearlike thrusts to supply their wants. Herons, unlike our Ibises and 

 Cranes, fly with their folded neck drawn in between their shoulders. 

 Their voice is a hoarse squawk. The young are born with a scanty 

 covering of long, filamentous down and are reared in the nest. In 

 feeding, young Herons, and possibly also young Bitterns, take a scissor- 

 like grasp of the base of the parent's bill with their own, when the 

 parent disgorges food into the nest or skillfully into the mouth of the 

 young. 



KEY TO THE SPECIES 



I. Wing over 13*00. 



A. Plumage pure white. 



a. Wing 17*00 or over; feathers on the lower neck long, narrow. 



192. GREAT WHITE HERON. 

 6. Wing under 17*00; neck-feathers not lengthened. 



196. AM. EGRET. 



B. Upperparts generally slaty or grayish blue. 



1946. WARD'S HERON. 194. GREAT BLUE HERON. 

 II. Wing under 13*00. 



1. Crown without streaks. 



A. Crown white or whitish. 

 a. Wing over 11*00. 



a 1 . Plumage entirely or mostly white .... 198. REDDISH EGRET. 

 a 2 . Plumage gray streaked with black; throat and sides of neck. 



black 203. YELLOW-CROWNED NIGHT HERON. 



6. Wing under 11*00. 



6 1 . Plumage pure white; legs and bill black; feet yellow. 



197. SNOWY HERON. 



6 2 . Tips of primaries slate-color; plumage white, sometimes irregu- 



larly marked with slaty blue . 200. LITTLE BLUE HERON (Im.) 



B. Crown not white or whitish. 



a. Crown umber or reddish brown. 



a 1 . Head and neck reddish brown; body slate-color. 



198. REDDISH EGRET. 

 a 2 . Neck conspicuously streaked ; body variegated. 



190. AM. BITTERN. 

 6. Crown not umber or reddish brown. 



ft 1 . Crown slaty or slate-blue with sometimes a purplish cast. 



6 2 . Wing-coverts more or less margined with rufous. 



199. LOUISIANA HERON. 



6 3 . Wing-coverts without rufous . . 200. LITTLE BLUE HERON. 

 c 1 . Crown not slaty, but greenish or bluish black. 



c 2 . Wing over 10*00; entire underparts pure white. 



202. BLACK-CROWNED NIGHT HERON. 



