194 
David S. Lee and Mary K. Clark 
Body mass — Little information is available on masses of 
swallow-tailed kites, and examinations of museum labels indicates 
that few specimens in collections contain mass information. For 
example, Dunning (1984) found reference to only two unsexed 
swallow-tailed kites that weighed 445 and 504 g for his mono- 
graph on body masses of North American birds, and Robertson 
(1988) cited only five recorded masses for the North American 
race. Of the 75 birds we examined in museum collections, we 
found only two with information on mass (see below). Of the se- 
ries we collected, four adult males averaged 550.6 g (range = 520.0- 
576.1), and five adult females averaged 613.0 g (range = 551.0-654.5). 
The heavier masses of adult females compared to adult males 
corresponds with the sexual size dimorphism already documented 
for the Species (Friedmann 1950). Immature birds weighed less than 
adults (2 males x = 481 g, range = 459-503 g). John Cely (South 
Carolina Wildlife and Marine Resources Department, personal 
communication) provided information on masses of six birds he 
followed in telemetry studies in South Carolina. The one of known 
sex was a female that weighed 510 g. The other five adults (sex 
unknown) weighed 440-502 g (x = 471.4). Males from south Florida 
weighed 475 and 422.7 g (Robertson 1988). 
Table 2. Molt of primary feathers on 11 swallow-tailed kites collected on the St. 
Johns River, Florida, July 1982. All from this study except the American Museum 
(AMNH) specimen, which is from the same general locality and was collected on 
14 July 1877. Feather condition, O = old, S = in sheath, N = new. 
Primary Numbers 
NCSM 
10 
9 
8 
7 
6 
5 
4 
3 
2 
1 
male 8521 
O 
O 
0 
O 
o 
0 
0 
O 
S 
N 
male 8525 
O 
O 
0 
O 
o 
0 
o 
O 
S 
S 
male 8527 
O 
O 
0 
0 
0 
0 
s 
N 
N 
N 
male 8502 
O 
O 
0 
0 
0 
0 
0 
N 
N 
N 
female 8523 
O 
O 
0 
0 
0 
0 
0 
O 
O 
S 
female 8479 
O 
O 
0 
0 
0 
s 
N 
N 
N 
N 
female 8522 
O 
0 
0 
0 
0 
0 
0 
O 
N 
N 
female 8504 
O 
0 
0 
0 
0 
0 
s 
N 
N 
N 
female 8503 
O 
0 
0 
0 
0 
0 
0 
N 
N 
N 
female 8526 
female (AMNH 
O 
0 
0 
0 
0 
0 
0 
N 
N 
N 
352031) 
O 
0 
0 
s 
s 
N 
N 
N 
N 
N 
