Musyl et al.: Postrelease survival, vertical and horizontal movements, and thermal habitats of five species of pelagic sharks 
357 
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ID TL(cm) 
Lat 
Lat. 
Year 
B13083F 
na 
19 
23 
2001 
B13087M 
204 
19 
26 
2001 
B13098F 
150 
30 
22 
2001 
B13503F 
187 
31 
25 
2002 
B13096F 
173 
30 
8 
2001 
B13093F 
160 
28 
29 
2001 
BI3215F 
200 
31 
29 
2002 
B 1349 IF 
215 
31 
24 
2002 
B13499F 
175 
31 
18 
2002 
B13497F 
200 
22 
35 
2002 
B27322M 
148 
31 
34 
2002 
SF38572F 
210 
22 
29 
2003 
BI3095F 
160 
29 
17 
2001 
B13097F 
183 
31 
26 
2001 
B13111F 
152 
30 
14 
2001 
SF46583F 
na 
19 
19 
2007 
T28476 
na 
19 
16 
2002 
T29481 
200 
19 
20 
2002 
E509 
130 
19 
20 
1998 
T46582 
na 
19 
20 
2004 
R46576 
na 
18 
27 
2004 
S3 857 3 M 
170 
19 
10 
2003 
S3 8 58 IF 
140 
19 
14 
2003 
O13092F 
120 
19 
24 
2001 
L38607 
na 
20 
10 
2003 
046568M 
na 
19 
24 
2004 
K 13208 
na 
-14 
-11 
2002 
046589F 
na 
19 
19 
2005 
S46588M 
1 37 
18 
18 
2004 
046587 M 
na 
18 
16 
2005 
O46570F 
na 
18 
15 
2005 
046581 M 
100 
20 
16 
2004 
013U3M 
na 
8 
8 
2005 
038582M 
115 
29 
-9 
2003 
04 6 5 69 M 
127 
19 
9 
2005 
S38599M 
200 
19 
19 
2003 
S38601M 
200 
19 
21 
2003 
03857 5 M 
200 
21 
25 
2003 
038598M 
200 
20 
16 
2003 
038576M 
200 
19 
19 
2003 
S46564M 
na 
1 
7 
2005 
S46590F 
1 16 
8 
8 
2005 
S46566M 
na 
7 
7 
2005 
S46585M 
120 
5 
6 
2005 
r~ 
1 00 
Kolmogorov-Smirnov I),..,.. Distance 
n.on 
Figure 8 
Dendrogram of epipelagic and mesopelagic species clusterings for five species of 
sharks, determined with unweighted pair-group method using arithmetic averages 
(UPGMA) and daytime temperature preference readings from pop-up satellite tags 
(PSATs). ID abbreviations: B=blue shark (Prionace glauca), SF=shortfin mako ( Isurus 
oxyrinchus), T=bigeye thresher ( Alopias superciliosus), E=bigeye tuna ( Thunnus 
obesus ), R = swordfish (Xiphias gladius), S = silky shark (Carcharhinus falciformis), 
0 = oceanic whitetip shark (C. longimanus), K=black marlin ( Istiompax indica), 
L = blue marlin ( Makaira nigricans), M=male, and F=female, TL=total length (cm) 
and PSAT deployment and pop-up latitude are provided with pop-up year. na=not 
available. Outgroup data were taken from Pacific swordfish, black marlin, blue 
marlin (Musyl et al. 2 ) and bigeye tuna (Musyl et al., 2003). Italic and bold fonts 
are used to distinguish the various species groupings. 
have noted (e.g., Hight et al., 2007; Erickson and 
Berkeley, 2008; Walsh et al., 2009), presumably be- 
cause of species-specific tolerances to stress and in- 
juries (Hight et al., 2007; Mandelman et al., 2008; 
Mandelman and Skomal, 2009). For example, in the 
Pacific, Hight et al. (2007) reported blue sharks to 
exhibit significantly lower catecholamine levels than 
shortfin makos during retrieval of longline gear. The 
difference agrees with results indicating much low- 
er at-vessel mortality for blue sharks (Walsh et al., 
2009). 
Species-specific vertical and horizontal movements 
Our results strongly indicate that pelagic sharks exhibit 
high levels of individual variability in their vertical 
movement patterns and these are significantly influ- 
enced by time of day, and the transitions from daytime 
to nighttime diving activity can be dramatic. Plasticity 
in diel vertical movement patterns has also been docu- 
mented in bigeye tuna (Musyl et al., 2003) and southern 
bluefin tuna (T. maccoyii, Bestly et al., 2009) and other 
pelagic species (Arnold and Dewar, 2001; Gunn and 
