THE WHISTLING SWAN. 



571 



depths. When one gets "hot" in this ancient game of hide-the-thimble, the 

 most interested pair of birds will single themselves out from the hovering 

 throng and prepare for defense. Unless their advances are early discour- 

 aged, the boldness of these two will increase until they actually strike the 

 intruder on the head, to say nothing of frec[uent salutations with flying 

 shearn. At the same time the characteristic cry, krik, krik, — hoarser and 

 deeper than that of the Common Tern, and lacking its nasal resonance — is 

 flatted by anger into kra-ack, kra-ack. 



The nests are usually placed upon floating vegetation, or upon bars of 

 incipient land at the edge of the bayou — never, in my experience or in that 

 of Professor Jones, upon the tops of muskrat houses, either new or old. 

 They vary in construction from the almost imperceptible mud hollow, through 

 the water-soaked circlet of retaining trash, to the more pretentious high-and- 

 dry heap, shown in the illustration. The pale olive-brown eggs, heavily 

 spotted and blotched with blackish brown, harmonize so perfectly with their 

 surroundings of decaying and mud-spattered vegetation, as almost to elude 

 the sight even after being once discovered. 



No. 273. 



WHISTLING SWAN. 



A. O. U. No. 180. Olor columbianus (Ord.). 



Description.— Adult : Entire plumage pure white, the head sometimes tinged 

 with rusty ; bill and lores black, the latter usually with a distinct yellow spot near 

 eye; feet and legs black. Immature: Plumage ashy gray, the head and neck 

 tinged with brownish; bill and feet light. Length about 54.00 (1371.6) ; extent 

 seven feet; wing 21.25 (539-8) ; tail" 8.50 (215.9) ; bill 4-oo (101.6) ; tarsus 3.90 

 (99.1) ; middle toe and claw 5.40 (137.2). 



Recognition Marks. — Eagle size; pure white plumage; long neck; small 

 yellow spot on lores distinctive for this species. 



