Jackson and Wadley. Age, growth, and reproduction of Nototodarus hawaiiensis 
781 
y = 0.95.x - 7.75 (r 2 = 0.75) 
and 
y - 1.08.x - 14.915 (r 2 = 0.78), 
for males and females respectively, 
where x = increment number; and 
y = mantle length (mm). 
The increment count for males ranged from 71 (42 
mm ML) to 192 (164 mm ML). Statolith increments 
in the largest male collected (176 mm ML) could not 
be counted owing to overgrinding of the statolith. The 
increment count for females ranged from 49 (48 mm 
ML) to 195 (183 mm ML). The largest female (214 
mm ML) had an increment count of 179. 
Male maturation patterns 
The largest immature male was 127 mm ML and had 
167 statolith increments. Males appeared to mature 
as early as 100 d and 90 mm ML. Mature males 
showed considerable range in weights of testis (from 
0.92 g to 2.84 g, Fig. 3A). 
On the basis of ML alone, testis weight appeared 
to increase rapidly with growth (Fig. 3A), and there 
was some evidence of testis regression (on the basis 
of reduced testis weight relative to ML) at larger 
sizes. However, when testis growth was compared 
with increment number, there was no clear pattern. 
Plotting testis weight against increment number 
showed that mature individuals varied widely in age 
and individuals of similar age varied widely in testis 
weight (Fig. 3B). 
Female maturation patterns 
The largest immature female was 166 mm ML and 
had 192 statolith increments, whereas the smallest 
mature female was 136 mm ML and had 146 sta- 
tolith increments. All females larger than 166 mm 
ML were mature on the basis of the presence of ma- 
ture oocytes. On the basis of ML (Fig. 4A), females 
reached full maturity over a narrow length range 
between approximately 136 and 170 mm ML. How- 
ever, as with testis weight for the males, ovary weight 
plotted against increment number (Fig. 4B) showed 
considerably more variability than did ovary weight 
plotted against ML (Fig. 4A). The youngest mature 
female was 125 d. It appeared that there was little 
growth in the ovary before 100 d. 
The largest immature female ( 166 mm ML) had a 
NGL of 48 mm ML. Whereas the smallest mature 
female (136 mm ML) had a NGL of 51 mm, all ma- 
ture females had a NGL greater than 38 mm. All 
immature individuals had a NGL less than 50 mm. 
The trend in growth of the nidamental gland fol- 
lowed a similar pattern for either ML or incre- 
ment number (Fig. 5, A and B). 
Hatching dates 
On the assumption that statolith increments are 
formed daily, hatching dates were backcalculated. 
All individuals that were aged hatched between 
July and December 1991; the majority (83%) 
hatched between August and November, and 7 1% 
hatched in August, September, and October (Fig. 
6). Most squid hatched during the austral spring 
(September-November), although there was 
some hatching in late winter (July) and early 
summer (December). 
Statolith microstructure 
and growth zones 
The statoliths of N. hawaiiensis generally had 
clear increments that could be counted from the 
nucleus to the outer margin of the dorsal dome 
(Fig. 7). There was a pattern in the zonation in 
nine of the 42 statoliths examined (Fig. 7, A and 
B). Some individuals had a distinct inner opaque 
zone followed by an outer translucent zone (Fig. 
