Heftier et al.: Variability in abundance of larval fishes inside Beaufort Inlet 
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Figure 1C 
Nightly mean densities (three tows each night) of larval southern flounder, 
Paralichthys lethostigma, and gulf flounder, Paralichthys albigutta, caught 
near Beaufort Inlet, North Carolina. 
Results 
Species abundance 
The eight species selected for analysis accounted for 
92% of the larvae caught during the period and are 
listed in Table 1 in order of decreasing abundance. 
Although abundance was not predictable from one 
night to the next for any species (Fig. 1, A-D), the 
Durban- Watson statistics for the polynomial regres- 
sion models detected significant autocorrelation in 
the residuals for six of the eight species. However, 
one could not reject the null hypothesis that, for 
Mugil cephalus and for Paralichthys albiguitta, the 
test was inconclusive. The first-order autocor- 
relations for the other six species ranged from 0.30 
for Paralichthys dentatus to 0.52 for M. undulatus. 
These reflect the serial dependency between densi- 
ties on successive nights. On many dates, densities 
were two or more times less or more than the night 
