72 
Fishery Bulletin 11 7(1-2) 
Table 1 
Indices used to determine basic maturity in female porbeagles (Lamna nasus) 
based on data from Jensen et al. (2002) for female porbeagles caught between 
Georges Bank and the Grand Banks of Newfoundland, Canada, during 1979-1999. 
Adapted from Walker (2005b; table 4.1). 
Organ 
Index 
Description 
Maturity classification 
Upper oviduct 
UO-1 
<4.9 mm 
Immature 
UO-2 
>5 to <7 mm 
Uncertain 
UO-3 
>7 mm 
Mature 
Oviducal gland 
OG-1 
<21 mm 
Immature 
OG-2 
>21 to <24 mm 
Uncertain 
OG-3 
>24 mm 
Mature 
Ovary length 
OL-1 
<104 mm 
Immature 
OL-2 
>104 to <121 mm 
Uncertain 
OL-3 
>121 mm 
Mature 
Ovary width 
OW-1 
<75.0 mm 
Immature 
OW-2 
>75.0 to <86.6 mm 
Uncertain 
OW-3 
>86.6 mm 
Mature 
Uterus length (total) 
UL-1 
<343 mm 
Immature 
UL-2 
>343 to <475 mm 
Uncertain 
UL-3 
>475 mm 
Mature 
Uterus width 
UW-1 
<26 mm 
Immature 
UW-2 
>26 to <43 mm 
Uncertain 
UW-3 
>43 mm 
Mature 
Membrane 
Present 
Immature 
Absent 
Mature 
tracts were measured on the right side of the specimen 
following Pratt (1979, 1993, 1996) and, specifically for 
the porbeagle, Jensen et al. (2002). Terminology follows 
Hamlett and Koob (1999) and Hamlett (1999), except 
where noted. 
Reproductive organ measurements, taken to the 
nearest millimeter and at the widest part of the struc¬ 
ture, included anterior oviduct width, oviducal gland 
width, ovary width and length, and uterus width and 
length. As per Jensen et al. (2002), 2 measurements 
were taken on the uterus: 1) from the anterior origin 
of the uterus to the vagina and 2) from the anterior 
origin of the uterus to the junction of the uteri (see 
fig. IB in Jensen et al., 2002). Uterus width was taken 
midway along the anterior portion of the uterus (see 
fig. IB in Jensen et al., 2002). For each ovary, oocytes 
were classified as mature if they contained yellow, vi¬ 
tellogenic material. The largest oocyte was measured 
in the field. 
Males and females were classified as immature or 
mature, and mature females were further divided into 
4 stages: ovulating, pregnant, postpartum, and resting. 
Using data from Jensen et al. (2002), we developed cri¬ 
teria for basic maturity classification (Table 1). Prior 
mating activity was assessed on the basis of the pres¬ 
ence (immature) or absence (mature) of a vaginal mem¬ 
brane (hymen), and whether mating occurred recently 
was assessed on the basis of presence or absence of in¬ 
ternal and external mating scars. The maturity stages 
of females were further determined by dissection: indi¬ 
cations of past pregnancy included flaccid uteri (Pratt, 
1979) and reduced ovaries with few mature or matur¬ 
ing oocytes. Individuals that appeared to have given 
birth in the current year were classified as postpartum, 
and those that had given birth but not recently were 
considered to be in a resting stage. A recently post¬ 
partum specimen was characterized by the presence of 
flocculent material consistent with portions of nutritive 
capsules along with milky uterine fluid (Gilmore et al., 
2005); the uteri of a postpartum fish are very flaccid, 
and trophonemata are present (Natanson and Gervelis, 
2013). Postpartum ovaries are generally large, hema- 
tose, and contain atretic oocytes. 
Resting ovaries are often similar in appearance to 
the ovaries of almost mature juvenile sharks. It is, 
therefore, difficult to stage these fish by ovary condi¬ 
tion alone, and other organ characteristics must be 
taken into account (Natanson and Gervelis, 2013). A 
late juvenile fish has a thin tubular uterus in contrast 
to the wider, slightly flaccid appearance of the rest¬ 
ing uterus (previously expanded and then recovered) 
of adults. Additionally, a late-stage juvenile fish has a 
