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Fishery Bulletin 106(4) 
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Distance from outer reefs (km) 
Figure 3 
Mean abundance (larvae/100 m 2 +l [± standard 
error]) of Thunnus alalunga (albacore) larvae 
with distance from the outer reefs of the Great 
Barrier Reef during the early November, late 
November, and early February cruises in the 
Coral Sea. Data points indicate the midpoint 
of sampling blocks (A-E) by distance, except 
for the Great Barrier Reef Lagoon (L on the 
x axis) the display of which is categorical and 
does not reflect the true distance from the 
other blocks. The y axis is log 10 scale. The x 
axis shows the width of each sampling block 
(km). The hatched area on the x axis indicates 
the position of the outer reef area of the Great 
Barrier Reef. Within a cruise, if data points 
share a lowercase letter, they were not signifi- 
cantly different from each other according to 
Tukey’s post hoc test. Abundance data were 
not obtained for block D. 
(K-S test, P<0.01, Fig. 7A) and late February (K-S test, 
P<0.02, Fig. 7B) cruises. A similar pattern was found 
for the late November cruise, with the result approach- 
ing significance (K-S test, 0.05<P<0.10, Fig. 7C). De- 
spite a greater proportion of smaller larvae present in 
the inshore zone, small (~2 mm SL) K. pelamis larvae 
were present in the offshore zone on all cruises. There 
was also a greater proportion of small (3-4 mm SL) T. 
albacares larvae in the inshore zone, compared with 
Figure 4 
Mean abundance (larvae/100 m 2 +l [± standard error]) 
of Thunnus albacares (yellowfin tuna) larvae with dis- 
tance from the outer reefs of the Great Barrier Reef 
during the early February cruise in the Coral Sea. Data 
points indicate the midpoint of sampling blocks (A-E) 
by distance, except for the Great Barrier Reef Lagoon 
(L on the x axis) the display of which is categorical and 
does not reflect the true distance from the other blocks. 
The y axis is log 10 scale. The x axis shows the width 
of each sampling block (km). The hatched area on the 
x-axis indicates the position of the outer reef area of 
the Great Barrier Reef. No significant differences were 
found among blocks (ANOVA, P=0.06). Abundance data 
were not obtained for block D. 
the offshore zone, on the early February cruise (K-S 
test, P<0.02, Fig. 8). Not enough T. albacares larvae 
were caught in each zone on other cruises for statisti- 
cal analysis; however examination of size-frequency 
data indicated that there may also have been a greater 
proportion of smaller T. albacares larvae in the inshore 
zone on the late November cruise. No significant dif- 
ferences in size-frequency distributions were found for 
T. alalunga larvae between the inshore and offshore 
zones on either the early November (K-S test, P>0.2, 
Fig. 9A) or late November (K-S test, P> 0.2, Fig. 9B) 
cruises. There was also no significant difference in the 
size of Auxis-Euthynnus larvae between the inshore and 
offshore zones on the early February cruise (K-S Test, 
P>0.2, Fig. 9C). 
Discussion 
Mean near-reef (<4 km offshore) abundances of tuna 
larvae in the Coral Sea (range 20-120 larvae/100 m 2 ) 
were similar to those found around the Hawaiian island 
of Oahu (-3-80 larvae/100 m 2 , Boehlert and Mundy, 
1994) and similar to estimates of near-reef abundance 
from French Polynesia (45-75 larvae/100 m 2 , Leis et 
ah, 1991). Although these values were not much greater 
