596 
Fishery Bulletin 99(4) 
nificantly different, even when the analysis was limited 
to ages 8 to 13 years. However, our conclusions are lim- 
ited to primarily younger fish because most of the fish 
in our study were less than 11 years old. Pattison and 
McAllister recommended sectioned otoliths for fish aged 
11 years or older. Nonetheless, we concur that use of sec- 
tioned otoliths in older individuals may reduce the varia- 
tion in assigned ages. 
We feel that the larger percentage of unreadable whole 
otoliths in central California versus southern California was 
due primarily to the preparation techniques used for age 
determination. The anise oil used in the initial handling of 
some central California otoliths created a white film that pre- 
cluded the otoliths from being read at a later time. Because of 
problems encountered with anise oil, we do not recommend 
applying it to otoliths until one is ready to age them. 
Table 6 
Mean total length (mm) and standard deviation for male and female California halibut by age group in southern California. Mann- 
Whitney comparisons of male and female halibut for mean length at age. Asterisk (*) indicates statistical significance. 
Male Female 
Age Mann-Whitney 
(yr) 
n 
Mean 
SD 
Min 
Max 
n 
Mean 
SD 
Min 
Max 
P-value 
1 
4 
259.3 
25.0 
232 
290 
i 
252.0 
— 
252 
252 
— 
2 
103 
289.4 
28.4 
210 
369 
21 
291.9 
38.4 
241 
368 
0.77 
3 
178 
319.3 
39.3 
220 
411 
42 
364.4 
63.9 
254 
477 
0.0001* 
4 
no 
377.3 
42.2 
291 
501 
54 
462.6 
86.7 
342 
660 
0.0001* 
5 
106 
417.2 
55.0 
294 
561 
58 
520.5 
64.3 
389 
671 
0.0001* 
6 
92 
481.7 
61.9 
362 
646 
70 
591.2 
67.7 
401 
735 
0.0001* 
7 
97 
505.6 
65.1 
399 
645 
41 
616.1 
60.5 
493 
758 
0.0001* 
8 
40 
538.3 
62.6 
403 
707 
26 
666.0 
101.4 
492 
859 
0.0001* 
9 
23 
551.5 
68.0 
451 
707 
11 
736.2 
131.9 
534 
934 
0.0002* 
10 
6 
578.2 
34.5 
542 
619 
9 
828.3 
67.4 
720 
937 
0.002* 
11 
1 
577.0 
— 
577 
577 
2 
836.0 
213.5 
685 
987 
— 
12 
1 
586.0 
- 
586 
586 
— 
— 
— 
— 
— 
— 
13 
— 
— 
— 
— 
— 
1 
964.0 
— 
964 
964 
— 
Total 761 336 
Table 7 
Mean total length (mm) and standard deviation for male and female California halibut by age-group in central California. Mann- 
Whitney comparisons of male and female halibut for 
mean 
length at age. Asterisk (*) 
indicates statistical significance. 
Age 
(yr) 
Male 
Female 
Mann-Whitney 
P-value 
n 
Mean 
SD 
Min 
Max 
n 
Mean 
SD 
Min 
Max 
2 
15 
325.9 
29.8 
285 
381 
12 
312.9 
28.7 
262 
367 
0.29 
3 
46 
384.8 
38.1 
293 
472 
46 
373.4 
70.0 
279 
593 
0.02* 
4 
26 
447.8 
60.5 
380 
660 
35 
493.5 
102.3 
328 
820 
0.07 
5 
9 
492.8 
59.0 
424 
582 
17 
606.2 
101.4 
474 
758 
0.007* 
6 
20 
538.6 
49.4 
479 
680 
4 
672.0 
87.0 
582 
782 
0.006* 
7 
13 
595.6 
72.7 
490 
748 
2 
725.5 
43.1 
695 
756 
0.05* 
8 
13 
582.5 
74.4 
475 
719 
5 
810.4 
99.3 
694 
925 
0.002* 
9 
3 
648.7 
29.5 
619 
678 
5 
842.0 
112.2 
547 
923 
— 
10 
1 
781.0 
— 
781 
781 
1 
970.0 
— 
970 
970 
— 
11 
1 
737.0 
— 
737 
737 
— 
— 
— 
— 
— 
— 
12 
— 
— 
— 
— 
— 
2 
1026.5 
17.7 
1014 
1039 
— 
Total 
147 
129 
