Vilella and Nimitz • RED-TAILED HAWKS IN THE LUQUILLO MOUNTAINS 
761 
TABLE 1. Red-tailed Hawks captured and radiomarked. and home ranges 
Capture date Months tracked Number of locations Gender' 
1 
6 /20/00 
8 
79 
u 
2 
6/29/00 
2 
29 
u 
4 
3/05/01 
14 
84 
F 
5 
3/07/01 
14 
110 
M 
6 
3/12/01 
11 
65 
M 
7 
4/03/01 
5 
32 
F 
8 
5/04/01 
8 
63 
F 
9 
5/14/01 
12 
69 
F 
12 
7/06/01 
7 
44 
F 
13 
7/13/01 
10 
60 
M 
14 
7/13/01 
7 
42 
F 
15 
2/14/02 
5 
33 
F 
16 
2 /20/02 
5 
50 
F 
17 
3/12/02 
4 
37 
M 
18 
3/14/02 
3 
37 
M 
19 
4/04/02 
3 
37 
F 
20 
5/15/02 
2 
37 
M 
21 
5/16/02 
2 
37 
M 
22 
5/20/02 
2 
37 
F 
23 
5/31/02- 
2 
37 
F 
24 
5/31/02 
2 
37 
F 
'' (iender: U 
Age: HY 
= unknown, 
= hatch-year. 
F = female. M = male. 
AHY = after-hatch year. SY 
second-year. ASY ; 
= after-second 
’ Home range: 95*5 fixed kernel (ha). 
" Core area: 509!; fixed kernel (ha). 
in the Luquillo Mountains, Puerto Rico. 
Age" Home range' Core area' 
AHY 
8.635 
SY 
2,849 
ASY 
1.320 
ASY 
1.483 
AHY 
2,317 
SY 
14.734 
AHY 
5.724 
AHY 
1.408 
HY 
1,853 
HY 
28.791 
HY 
7.401 
ASY 
8.854 
AHY 
8.644 
SY 
1.312 
ASY 
11.288 
ASY 
7.228 
HY 
1,660 
HY 
532 
HY 
571 
HY 
305 
HY 
362 
520 
427 
236 
150 
312 
1.883 
598 
190 
317 
3.601 
519 
1.226 
925 
210 
1.230 
1.047 
149 
69 
62 
40 
80 
Hawks in the Luquillo Mountains averaged 
5,022.6 ± 832.1 ha (305-11.288 ha) and core 
areas averaged 564.8 ± 90.7 ha (150-1,230 ha). 
The home range of paired Red-tailed Hawks 
averaged 4,584 ± 420.6 ha (1,312-11,288 ha) lot- 
males and 5,219.7 ± 1,395 ha (1,320-8.854 ha) 
for females. Home range of juvenile males 
U.096 ha) was more than twice that of juvenile 
females (412.6 ha). Breeding season home range 
of Red-tailed Hawks did not differ by age (/’i .5 = 
0.83, P = 0,40) or gender (F j.s = 0.02, P = 0.89). 
Red-tailed Hawks in the Luquillo Mountains 
exhibited high spatial overlap and essentially 
complete coverage of LI Yunque (F ig. 2). 
Weekly movements averaged 3,063.1 ± 
348.5 m (range = 1.652-5.090 m). Movements 
of juveniles during the post-fledging dependency 
period averaged 1.348 ± 264.2 m (Table 2). Red¬ 
tailed Hawk weekly movements during the 
breeding season did not differ by age (F t . 6 = 
0-01. P = 0.93) nor gender (F i.<, = 0.46, P = 
0.52). We detected shifts in Red-tailed Hawk core 
area use (Table 3). The breeding season core area 
used by one after-second-year female (RTHA 4) 
decreased 69% (6 = -6.53, P ^ 0.001) from 
2001 (205 ha) to 2002 (64 ha) and differed from 
the non-breeding season to the breeding season (5 
= -8,90, p < 0.001). Similarly, one adult male 
(RTHA 5) shifted core area used from the 
breeding to non-breeding season (6 = -4.81. P 
= 0.002) and from non-breeding season to 
breeding season (6 = -4.29, P = 0.003). A 
juvenile male (RTHA 13) exhibited the greatest 
shift in core area (6 = -7.37, P ^ 0.001). Red¬ 
tailed Hawks in the Luquillo Mountains exhibited 
non-random patterns in habitat use (Wilks’ X = 
0.1346, /^io f, = 3.86. P = 0.05) and used roadside 
habitats more than palo Colorado forest (P — 
0.001), agriculture (P = 0.002), rivers (P = 
0.002), and pasture (P = 0.005). Roadside 
habitats were used more than wetlands (P < 
0.001). urban (P < 0.001), sierra palm forest (P = 
0.001), and subtropical moist forest (P = 0.001). 
DISCUSSION 
Neotropical buteos generally search from 
perches and initiate attacks once prey is detected 
(Panasci and Whiiacre 2000). Retention of perch 
hunting behavior has been documented in other 
insular forms of the Red-tailed Hawk and closely 
related species including the Hawaiian Hawk (B. 
soliturius) (Walter 1990. Klavilter et al. 2003). 
This behavior may be facilitated by the availabil¬ 
ity of perches in tropical forests (Wunderle 1997). 
