O'Malley et al.: Effects of exploitation evident in age-based demography of Pristipomoides flavipinnis and P. auricilla 
327 
The estimate of natural mortality from the multinomial 
catch curve for the unfished populations was used as the 
value for natural mortality in the associated fished popu¬ 
lations. The set of equations used to calculate total mortal¬ 
ity in the fished areas is similar to the previous equations 
(with f in the superscript instead of unf to indicate the 
fished areas), with the following modifications: 
cl =S a f ^Ml-e -z “), 
(11) 
Z a =M + F a , 
(12) 
F a =FV{, and 
(13) 
S a f = SI ie“ z ", 
(14) 
where C a = expected catch in numbers of age-a individuals 
in the fished areas; 
Z a = age-specific total instantaneous mortality; 
F a = fishing mortality at age; 
F = full fishing mortality; 
V{ = gear selectivity at age a in the fished areas; and 
S3 = survivorship in the fished areas. 
Expected catch in numbers of age-a individuals in the 
fished areas was calculated by using Baranov’s formula: 
age-specific total instantaneous mortality in the fished 
areas is the sum of natural mortality and fishing mortality, 
fishing mortality at age is the product of full fishing mor¬ 
tality and gear selectivity at age a in the fished areas, and 
survivorship in the fished areas is a negative exponential 
function of both natural mortality and fishing mortality. 
Selectivity was also assumed to follow a logistic function 
with parameters A 5 f 0 and A*. Values of natural mortality 
and total mortality, and the gear selectivity parameters in 
both regions, were simultaneously estimated by minimiz¬ 
ing the sum of nLL f and nLL un{ . The catch curve mortality 
parameters were estimated within AD Model Builder, 
vers. 12.0 (Fournier et al., 2012), and asymptotic standard 
errors were used in the calculations of the 95% confidence 
intervals (CIs) of the parameter estimates. 
Results 
Aging precision, and length and age compositions 
The measures of precision between readers for opaque 
zone counts from thin transverse sections of otoliths 
were within the acceptable ranges for deepwater snap¬ 
pers (Wakefield et al., 2017). The between-reader IAPE 
was 5.2% for aging of goldeneye jobfish; 47% of the sec¬ 
tions had exact agreement between readers, and age esti¬ 
mates were within 1 year for 80% of sections. The IAPE for 
aging of goldflag jobfish was 4.9%; 32% of the sections had 
exact agreement between readers, and age estimates were 
within 1 year for 92% of sections. 
The size and age of goldeneye jobfish ranged from 234 to 
474 mm FL and from 2 to 28 years old (Table 1, Fig. 2). 
Maximum estimated ages were similar for males (25 
years) and females (28 years) as were the maximum sizes 
(males: 451 mm FL; females: 474 mm FL). The results of 
Kolmogorov-Smirnov tests indicate no significant differ¬ 
ences between males and females in either size (D=0.231, 
P= 0.828) or age (.0=0.154, P=0.995) compositions. Analy¬ 
sis conducted with Kolmogorov-Smirnov tests revealed a 
significant difference in age compositions between fished 
and unfished areas (0=0.5556, PcO.OOl) but not in size 
compositions (0=0.385, P=0.226). The mean FL for com¬ 
bined sexes differed significantly between fished and 
unfished areas, with fish in unfished areas 41 mm larger 
on average than those in fished areas (F± 371 =0.22, P=0.00). 
Similarly, the mean age for combined sexes differed 
Table 1 
Estimates of the annual growth coefficient (K) and asymptotic length (L„) from the von Bertalanffy growth 
function, maximum ages (A max ), size ranges, and sample sizes ( n ), by sex and by area (fished and unfished), 
for goldeneye jobfish (Pristipomoides flavipinnis) sampled from the Samoa Archipelago in 2012 and 2016 and 
for goldflag jobfish (P. auricilla) sampled from the Mariana Archipelago in 2014. The 95% confidence inter¬ 
vals for estimates of K and L „ are provided in parentheses. Values of L m and in size ranges are fork lengths 
in millimeters. Combined=areas (fished and unfished) or sexes combined. 
Species 
Data set 
K 
L„ (mm) 
A 
max 
Size range (mm) 
n 
P. flavipinnis 
Female 
0.44 (0.41-0.48) 
418.6 (413.0-424.6) 
28 
234-474 
179 
Male 
0.51 (0.46-0.56) 
404.1 (398.4-409.8) 
25 
253-451 
194 
Fished 
0.37 (0.30-0.45) 
429.2 (402.5-463.5) 
10 
234-453 
61 
Unfished 
0.53 (0.50-0.58) 
407.9 (404.4-411.6) 
28 
315-474 
312 
Combined 
0.47 (0.44-0.50) 
411.5 (407.2-415.6) 
28 
234-474 
373 
P. auricilla 
Female 
0.56 (0.51-0.62) 
335.2 (327.8-343.1) 
32 
225-400 
106 
Male 
0.53 (0.49-0.58) 
358.9 (353.4-364.8) 
26 
240-403 
160 
Fished 
0.60 (0.55-0.66) 
325.2 (317.6-333.1) 
18 
164-347 
135 
Unfished 
0.54 (0.50-0.59) 
358.6 (353.6-363.8) 
32 
225-403 
160 
Combined 
0.51 (0.48-0.54) 
358.5 (347.5-357.5) 
32 
164-403 
295 
