113 
falls. This catastrophe has occurred several times within the last decade 
and hundreds of Swans have lost their lives in this manner; some have 
every bone in the body broken, whereas others are only slightly hurt. As 
the birds do not seem able in the close quarters to rise above the sides of 
the gorge, and show marked reluctance to pass beneath the bridges that 
span the lower pass, all are confined in the narrow waters below the fails 
where there is no escape. The flesh of the Swan is not usually very suitable 
for eating and the birds are of little value to those who take them except 
as curiosities. 
181. Trumpeter Swan. Cygnus buccinator. L, 65. A very large, white bird, like 
the Whistling Swan but larger and never with a yellow or orange spot in front of the eye. 
Distinctions. Because of its large size and entire whiteness, to be mistaken only 
Longitudinal section through sternum of Trumpeter Swan; 
scale, $. 
for the Whistling Swan. This is considerably the larger of the two Swans. Its 
weight is given as high as 36 pounds; the Whistling seldom goes over 18. Any Swan 
over 55 inches long, with a wing over 23 and weight above 20 pounds, is probably a 
Trumpeter. The bill characters usually given as distinctive are unreliable. The position 
of the nostril is not determinative. The Trumpeter never has a yellow spot in front of 
the eye like the Whistling, but its absence is not necessarily diagnostic. The only positive 
character for the separation of these species, except size, is the sternum or breast bone. 
In both these Swans the windpipe as it comes down from the neck enters the end of the 
keel bone which is thickened into a deep flat tube for the purpose, proceeds to the rear end 
of the sternum, and there, within the bony floor, forms a broad horizontal loop, returns, and 
forms another loop, rising perpendicularly in a hump just before it passes out of the sternum 
on its way to the lungs, by way of the same opening through which it entered. In the 
Whistling Swan this final loop is missing (compare Figures 145 and 146). The develop- 
ment of this labyrinth is progressive with age and undoubtedly follows much the same 
progress as in the Whistling Swan. A bird known to be 18 months old had a perpendicular 
loop raised 1-8 inches above the sternum floor, but the horizontal loop showed an angular 
return without broad loop, quite similar in development to a Whistling of the same age. 
It is doubtful, however ; if the species ever gets quite as broad an horizontal loop as do very 
old birds of that species. The fact that the perpendicular loop develops more rapidly 
than the horizontal one renders identification of young birds, by these characters, easy. 
Field Marks. Size and complete whiteness. In flight Swans carry their long necks 
outstretched like Cranes, but do not trail long legs behind. The best separation of the 
Trumpeter from the Whistling in life is probably the voice. That of this species is con- 
siderably deeper and more sonorous. This distinction, however, is recognizable only by 
those familiar with both species. 
Nesting. On the ground, nest of grass, moss, etc., lined with down. 
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