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Fishery Bulletin 107(4) 
a preliminary growth-rate estimation, based on daily in 12 months (M. Seki, personal communD.The sickle 
increments on otoliths, indicates that sickle pomfret pomfret growth and maximum size were estimated at 
has rapid growth and reaches 42-49 cm fork length just slightly less than the values for skipjack tuna, 
which has a P/B of 1.9 in the model; hence the 
sickle pomfret P/B was set at 1.5. Snake mack- 
erel is a relatively fast-growing species with a 
maximum size of 1.0 m and population doubling 
time of less than 15 months and therefore it 
was assigned a P/B of 1.0 whereas escolar has 
a maximum size of 2 m and is slower grow- 
ing than snake mackerel, and therefore it was 
assigned a P/B of 0.8. Recognizing that the 
P/B values for most of the 13 species are fairly 
subjective, we used them only to compute the 
change in the proportion of moderate and high 
P/B species in the catch where moderate and 
high P/B species are defined as those with P/B 
greater than or equal to 1.0. 
Results 
The results from the logbook and observer CPUE 
time series for the 13 species revealed statisti- 
cally significant linear trends in slopes (P<0.05) 
for 9 species — 5 declining and 4 increasing 
trends (Table 1, Figs. 1-4). Albacore tuna, bigeye 
tuna, blue shark, shortbill spearfish, and striped 
marlin all showed declining CPUE trends; skip- 
jack tuna, yellowfin tuna, ono, and lancetfish 
showed no significant trends; and mahimahi, 
sickle pomfret, escolar, and snake mackerel 
showed increasing trends (Table 1, Figs. 1-4). 
CPUE trends for albacore tuna, striped marlin, 
shortbill spearfish, bigeye tuna, and blue shark 
all decreased from 3% to 9% annually, CPUE 
trends for yellowfin tuna, skipjack tuna, ono, 
and lancetfish remained unchanged, whereas 
CPUE trends for mahimahi, sickle pomfret, 
escolar, and snake mackerel increased from 6% 
to 18% annually (Table 1, Fig. 4). For reference, 
the combined CPUE of all species caught in the 
deep-set fishery recorded in the observer data 
declined 4% annually. The species with declin- 
ing trends had trophic levels of 4.0 or larger and 
the species with increasing trends had trophic 
levels of 3.9 or less (Table 1). 
The mean annual trophic level of the top 13 
species in the catch, weighted by number of 
fish caught, has declined over the time series 
by about 0.19 (or 5%), from about 3.85 to 3.66 
(Fig. 5). The percentage of the catch of the top 
13 species composed of apex predators (trophic 
level 4 and higher) has declined from about 70% 
to 40% (Fig. 5). The percentage of the catch 
of the top 13 species with relatively high P/B, 
1 Seki, Michael P. 2009. Pacific Islands Fisheries 
Science Center, National Marine Fisheries Service, 
2570 Dole Street, Honolulu, HI 96822-2396. 
Year 
Figure 1 
Temporally and spatially adjusted monthly catch per 1000 hooks 
(CPUE) and linear trend lines from the generalized additive 
models for those species exhibiting a significantly declining 
trend in the Hawaii deep-set longline fishery, 1996-2006: (A) 
bigeye tuna (Thunnus obesus ), (B) shortbill spearfish (Tetraptu- 
rus angustirostris), (C) blue shark (Prionace glauca), (D) striped 
marlin ( Tetrapturus audax), (E) albacore (Thunnus alalunga). 
