102 BULLETIN 135, UNITED STATES NATIONAL MUSEUM 



and the females croak to invite the males to pay their addresses to them. The 

 females utter their coaxing notes all at once, and as each male evinces an equal 

 desire to please the object of his affection, he has to encounter the enmity of 

 many an adversary, who, with little attention to politeness, opens his powerful 

 bill, throws out his wings, and rushes with fury on his foe. Each attack is care- 

 fully guarded against, blows are exchanged for blows; one would think that a 

 single well-aimed thrust might suffice to inflict death, but the strokes are parried 

 with as much art as an expert swordsman would employ; and, although I have 

 watched these birds for half an hour at a time as they fought on the ground, I 

 never saw one killed on such an occasion; but I have often seen one felled and 

 trampled upon, even after incubation had commenced. These combats over, 

 the males and females leave the place in pairs. They are now mated for the sea- 

 son, at least I am inclined to think so, as I never saw them assemble twice on 

 the same ground, and they become comparatively peaceable after pairing. 



Miss CatheriDe A. Mitchell has sent me the following attractive 

 sketch of the "morning love dance," a more peaceful courtship per- 

 formance, of this species : 



As I turned over in my sleeping bag, a glimpse of a rosy glow in the sky roused 

 me to better appreciation of the world already awake around me. An old pine 

 tree hanging from the mountain of sand back of us, was outlined against a gor- 

 geous reflection in the peaceful waters of Lake Michigan; and in the smooth 

 sands of the shore surrounding us. There! The Japanese picture was complete 

 with a great blue heron in the foreground. But see! A little way farther down 

 the beach are more great blue herons. A group of them together with outspread 

 wings flapping slowly up and down, circling round and round. Eleven birds 

 first, later 14, circling sometimes around each other and sometimes in the one 

 large circle, somewhat as we used to do in dancing-school days. I watched the 

 graceful motions perhaps half an hour, spellbound by the weirdness of the scene. 



Nesting. — Many and varied are the nesting sites chosen by this 

 species in the different portions of its wide breeding range, but cer- 

 tain characteristics are common to the species everywhere. It is, as 

 most of the herons are, a sociable species, prefering to nest in closely 

 congested communities, varying in size from a few pairs to several 

 scores or even hundreds. Where trees are available it prefers to nest 

 in trees and usually selects the tallest trees available; but it often 

 nests in low trees, or bushes, or even on the ground. The location 

 of the nesting rookery probably depends more on an available food 

 supply for the young than on the presence of suitable nesting trees. 

 But, as the main object to be gained is security for the eggs and 

 young, a remote and more or less inaccessible locality is always 

 chosen. 



My first experience with the nesting habits of the great blue heron 

 was in the Penobscot Bay region on the coast of Maine, where I have 

 examined breeding colonies on the spruce-covered islands near Deer 

 Isle. Bradbury Island, lying northwest of Deer Isle in Penobscot 

 Bay, has long been known as a breeding place for great blue herons. 

 It is a high island with open pasture land in the center, but heavily 

 wooded at both ends with a dense forest of tall spruces and firs, with 



