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THE WILSON JOURNAL OF ORNITHOLOGY • Vol. 123, No. 2. June 2011 
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Sp f Ctr0g , rams of sounds produced by Scintillant Hummingbirds. (A): two types of vocalizations, a and b. Wing 
conci«L°ir,? e ' S also .P resenl - ,B); wir >g trill ("') produced by aduli males. A faint harmonic is present. (C): dive sound 
. . he Wmg tn (vv) ' an add,t, °nal trill (T2), a harmonic of the additional trill, and a sound pulse ( p). At least four 
stadon^Th,,^ TT L The f puls , es . are produced at the bot,om Of the dive, as the male passes over the female. (DC a 
wine trih tv » f, ,SP dy l ° a . fe 7 la , e m a cage< wh,ch consis, ed of alternating duplets of sounds. One duplet comprises the 
wing trill (w). alternating with duplets of sound a that are broadband. 
ment an individual ‘shuttle motion'. Twice, tht 
stationary shuttle display was performed to i 
female in a cage: with gorget flared, the malt 
shuttled from side to side (laterally) in front of tht 
cage, over a horizontal distance of ~20 cm. Tht 
male would abruptly roll his body (i.e.. rotate 
around his longitudinal axis) while arresting his 
lateral motion at the end of each shuttle, flap his 
wings with asymmetrical motions, and sweep his 
tail sideways through a range of angles. The wing' 
did not appear to strike each other or anythin* 
else, during these motions. 
The other two high-speed videos were of the 
traveling shuttle display. Unlike the stationary 
shuttle, in which the male tended to fly side-to- 
side OateraHy ) repeatedly through the same space, 
during the traveling shuttle, the male was 
continually flying forward towards the fenu*I e 
with little lateral motion. During this forward 
flight the male engaged in periodic body rotation-'*- 
tail rotations, and asymetrical wing kinematics 
similar to the stationary shuttle display (Fig 5AI- 
Shortly after finishing one shuttle motion, the bird 
would start another, rotating its body and tail in 
the opposite direction from the previous. The total 
time spent rotating the tail was 73 ± 9 msec In = 
5 shuttles from 2 videos); the liming between 
shuttle motions was 55 ± 13 msec (n = 2 
intervals). Therefore, the rate at which shuttle 
motions were performed was 7.8 Hz. No compo¬ 
nent of the shuttle sound was produced at a rale of 
7.8 Hz. and this striking visual component of the 
display kinematics did not appear to correspond to 
production of a single particular sound. 
