362 
Fishery Bulletin 118(4) 
Table 1 
Length-frequency distributions, by sex and maturity stage, for Pacific angel sharks (Squatina californica) captured in 
the eastern Gulf of California in Mexico between 1998 and 2005. 
Female 
Total 
length (cm) 
Immature Mature Total 
20-25 
25-30 
30-35 
35-40 
40-45 
45-50 
50-55 
55-60 
60-65 
65-70 
70-75 
75-80 
80-85 
85-90 
90-95 
95-100 
Total 
SOLOS ORORORORORS) 
~] — Se 
BESSCORMORHRTRewnee 
LPoopnpwSapwrenapnroono 
ror) co) 
Total length (cm) 
Immature Mature 
Males 
Immature Mature 
Females 
Figure 4 
Box plot of the relationship between total length and matu- 
rity stage for Pacific angel sharks (Squatina californica) 
captured from the eastern Gulf of California in Mexico 
during 1998-2005. The black dots indicate observed lengths 
by sex and maturity stage. The upper and lower parts of 
each box represent the first and third quartiles (the 25th 
and 75th percentiles), and the horizontal line is the median. 
The vertical lines that extend above and below each box 
indicate minimum and maximum values. 
from the GOC. In addition, a latitudinal gradient in the 
maximum reported sizes of Pacific angel sharks has been 
observed, with sharks being larger on the coast of California 
and decreasing in length toward the southern part of the 
BCP on the Pacific coast. For instance, Miller and Lea (1972) 
Immature 
Male Both sexes 
Mature Total Immature Mature Total 
Poococoococoe 
aADeasParPreqqgeqqgooge 
oot awenAnroono 
reported a maximum length of 152.4 cm TL for individuals 
from the coast of California, and Natanson and Cailliet 
(1986) reported an L;, of 107 cm TL for the same area (~70% 
of the maximum length). For individuals on the northern 
part of the BCP, Cartamil et al. (2011) reported lengths of 
120-130 cm TL; whereas, Villavicencio-Garayzar (1996) 
reported a maximum length of 117 cm TL for individuals on 
the southern part of the BCP. Ramirez-Amaro et al. (2017) 
reported an unusually large size of 180 cm TL for individu- 
als in this same area. For Pacific angel sharks in the Bay of 
La Paz, part of the GOC, Romero-Caicedo et al. (2016) 
reported that the largest sizes were 90-100 cm TL and esti- 
mated that the L;, for males and females was 75.6 and 
77.7 cm TL, respectively (~77% of the maximum length). In 
contrast, in the study described here and conducted in 
Sonora and Sinaloa, the observed maximum length of 
Pacific angel sharks was 100 cm TL, and the estimated L;, 
was 74.41 cm TL for females and 77.82 cm TL for males, 
values that correspond to 74% and 77% of the maximum 
length, respectively. 
The frequency distribution of lengths at a given time can 
vary because of different factors, including selectivity of 
fishing gear and the seasonal availability of the species in 
the area. Differences in the length-frequency distributions 
of Pacific angel sharks in the GOC have been reported. In 
this study, a peak of abundance was found for the length 
class of 85-90 cm TL for both sexes. However, for both sexes, 
Romero-Caicedo et al. (2016) reported a peak of abundance 
for individuals that were 60-90 cm TL. 
Female sharks often reach larger sizes than males 
(Castro, 2011), including sharks of the species smoothback 
angelshark (S. oculata) (Capapé et al., 2002), sawback 
