152 
Fishery Bulletin 111(2) 
Table 1 
Summary table of OTC-marked vertebrae samples from juvenile Shortfin Mako ( Isurus oxyrinchus) recaptured from 2000 
to 2010 in the Southern California Bight for this study. Samples are sorted by time at liberty, and information includes tag 
and recapture dates and fish lengths and sex. The average number of band pairs (from 3 independent readers) is provided 
for after the OTC mark and birth band mark (±1 standard error [SE] ). NL=either no length estimate or an unreliable one. 
*=fork length (FL) was converted from total length or alternate length (first dorsal to second dorsal fin). 
Fish ID 
Time at 
liberty 
(days) 
Tagging 
date 
Recapture 
date 
Tagging 
length 
(cm FL) 
Recapture 
length 
(cm FL) 
Sex 
Average 
number 
of band 
pairs after 
OTC mark 
(±1SE) 
Average 
number 
of band 
pairs after 
birth band 
mark (±1SE) 
A037789 
1594 
7/11/2000 
11/21/2004 
108 
200 
F 
7.3 (0.9) 
9.3 (0.7) 
A037559 
1512 
6/21/2001 
8/11/2005 
110* 
190* 
M 
8.7 (0.3) 
11.7 (0.3) 
A038423 
1198 
7/9/2005 
10/19/2008 
91 
157* 
M 
7.8 (0.6) 
11.5 (0.3) 
A037655 
1133 
7/06/2001 
8/12/2004 
00 
CD 
* 
157* 
F 
5.3 (0.2) 
8.2 (0.2) 
A038734 
836 
7/5/2004 
10/19/2006 
106* 
172* 
M 
5.0 (0.0) 
9.0 (0.0) 
A038611 
733 
6/19/2004 
6/22/2006 
111* 
152 
F 
4.0 (0.0) 
6.0 (0.0) 
A039992 
730 
7/28/2007 
7/27/2009 
92 
146 
M 
4.0 (0.0) 
6.0 (0.0) 
A039946 
555 
8/1/2007 
2/6/2009 
109 
150 
M 
2.5 (0.0) 
4.5 (0.0) 
A038623 
531 
6/22/2004 
12/05/2005 
130* 
154 
M 
2.3 (0.2) 
7.3 (0.2) 
A058923 
463 
6/30/2002 
10/06/2003 
o 
OO 
-X- 
139* 
M 
2.5 (0.0) 
5.2 (0.7) 
A058969 
446 
6/23/2003 
9/11/2004 
* 
GO 
125* 
M 
2.3 (0.2) 
4.7 (0.4) 
A040354 
407 
8/13/2009 
9/24/2010 
98 
137* 
M 
2.3 (0.2) 
3.8 (0.2) 
A039341 
400 
7/24/2007 
8/27/2008 
131 
160* 
M 
1.5 (0.0) 
5.5 (0.0) 
A058916 
382 
7/01/2002 
7/18/2003 
137* 
162* 
F 
1.5 (0.0) 
4.5 (0.0) 
A038924 
373 
7/21/2005 
7/29/2006 
129 
163* 
M 
2.0 (0.0) 
5.5 (0.3) 
A039374 
364 
7/15/2007 
7/13/2008 
129 
154 
M 
2.0 (0.0) 
7.0 (0.0) 
A038091 
350 
6/24/2005 
6/9/2006 
128 
135 
M 
2.0 (0.0) 
7.5 (0.3) 
A038404 
335 
7/8/2005 
6/8/2006 
117 
NL 
M 
1.5 (0.0) 
5.0 (0.3) 
A040327 
323 
8/11/2009 
6/30/2010 
96 
114* 
M 
2.0 (0.0) 
5.0 (0.6) 
A038589 
313 
8/14/2004 
6/23/2005 
124 
141* 
M 
1.5 (0.0) 
7.5 (0.6) 
A040251 
298 
8/4/2009 
5/29/2010 
105 
141* 
F 
1.0 (0.0) 
3.3 (0.3) 
A040374 
298 
8/15/2009 
6/9/2010 
100 
NL 
F 
1.2 (0.2) 
3.2 (0.2) 
A040302 
277 
8/8/2009 
5/12/2010 
89 
103 
M 
1.2 (0.2) 
3.5 (0.3) 
A039912 
270 
8/2/2007 
4/28/2008 
79 
98 
F 
2.3 (0.2) 
3.3 (0.2) 
A040788 
253 
8/23/2009 
5/3/2010 
124 
164* 
M 
0.8 (0.2) 
5.3 (0.2) 
A038854 
211 
7/29/2009 
2/25/2010 
108 
NL 
F 
0.8 (0.2) 
2.7 (0.2) 
A039669 
206 
6/14/2008 
1/6/2009 
92 
NL 
M 
1.0 (0.0) 
3.0 (0.0) 
A040798 
193 
8/24/2009 
3/5/2010 
122 
NL 
F 
1.0 (0.0) 
4.3 (0.2) 
A038445 
145 
7/10/2005 
12/2/2005 
88 
NL 
M 
1.0 (0.0) 
3.3 (0.3) 
Results of the vertebral centrum analysis are sum- distal to the OTC mark and 3.5, 3.5, and 3 distal to 
marized in Table 1, including time at liberty, average the birth band. 
number of band pairs observed distal to the OTC mark. All tagging activities occurred during summer 
and average number of band pairs observed distal to 
the birth band. In addition, Figure 3 shows banding 
patterns and band-pair counts for 5 vertebrae from 
Shortfin Mako at liberty from 206 to 1512 days. 
Visual band-pair counts (identified by arrows in Fig. 
3) were agreed upon post hoc by all 3 readers, and 
3 samples had full agreement among readers dur- 
ing independent readings; however, 2 samples did 
not have complete agreement during independent 
readings. Band-pair counts distal to the OTC mark 
for sample A037559 were 9, 9, and 8, and distal 
counts to the birth band were 12, 12, and 11. Sam- 
ple A039912 had band-pair counts of 2.5, 2.5, and 2 
months when translucent zones appeared in the verte- 
brae (Fig. 3). In contrast, both translucent and opaque 
zones were found at the outer edge of vertebrae for 
samples collected throughout the year without any ap- 
parent seasonal patterns. 
There were no significant differences among band- 
pair counts distal to the OTC mark (ANOVA; P= 0.978) 
or among total counts distal to the birth band (ANOVA; 
P= 0.955). Age bias was negligible: age-bias plots (Fig. 
4) and chi-square tests of symmetry showed no system- 
atic bias (P>0.05), confirming that differences were due 
to random error. Variability among reader counts was 
low with an APE of 4.36% and CV of 5.71% for counts 
