Acanthurus triostegus sandvtmtisis — Randall 
255 
precise length determinations. Although the 
lengths were recorded to 0.5 mm., it should be 
added that variations as great as 1 mm. from 
the original measurement were noted in un- 
biased tests of accuracy. 
Eleven of the 22 marked fish were recovered; 
all from the area of release. Two of these were 
recaptured a second time. Of the 9 fish taken 
before February 1, few, if any, showed signif- 
icant growth (Table 8). The 4 recovered on 
February 21 and 27 displayed a definite increase 
in size, indicating a resumption of growth dur- 
ing this month in the area tested and for the 
year 1954. 
One other marked fish caught in February 
and 2 in early March had regenerated the fin 
other than the caudal fin which had been cut 
and could not be distinguished from at least 1 
other fish of their respective caudal fin cate- 
gories. 
Although there is some indication of a rela- 
tionship between increasing water temperature 
and the onset of growth of these manini, the 
temperature data are inadequate to establish any 
definite correlation. Temperatures were taken in 
the canal at night between 9:30 and 12:00 P.M. 
about 3 in. beneath the surface (Table 9) . 
It should be emphazied that the temperature 
at the mouth of the Ala Wai Canal probably 
varies much more in a day or from day to day 
than the sea surface temperature off Oahu (mean 
water temperatures for Honolulu in 1955 are 
given in Hydrographic Office, 280, as follows: 
January 24.0; February 23.6; March 24.1). The 
TABLE 9 
Temperature at the Mouth of the 
Ala Wai Canal 
DATE 
TEMP. (° C.) 
Jan. 5 
22.8 
Jan. 20 
23.2 
Feb. 1 
23.1 
Feb. 27 
25.3 
Mar. 2 
24.7 
Mar. 21 
24.9 
Ala Wai area is not large and the water is there- 
fore more subject to change due to variation in 
insolation and atmospheric temperature than the 
open sea. Probably more important are the 
changes produced due to variation in the run 
off of water from Palolo and Manoa valleys 
which drains to the canal and to the ever variable 
tides which affect this estuarine region. In order 
to provide adequate data for the determination 
of a correlation, temperatures should have been 
taken at regular intervals each day and an anal- 
ysis of growth made in terms of average daily 
water temperatures. 
Growth of Tagged Adults 
The first tag used on the manini was the At- 
kins type (Rounsefell and Kask, 1945: 330, 
fig. 1 ) . It consisted of a single rectangular piece 
of white cellulose acetate, 5 X 28 mm. in size, 
and was attached through the back of the fish 
beneath the posterior part of the dorsal fin with 
4-lb. test monofilament nylon. Two small adult 
TABLE 8 
Recovery Size of Juveniles of Acanthurus triostegus sandvicensis Marked on January 5-6, 1954 
STANDARD LENGTH 
WHEN MARKED (mm.) 
STANDARD LENGTH WHEN RECAPTURED 
Jan. 20 
Jan. 26 
Feb. 1 
Feb.. 21 
Feb. 27 
40.0 
41.0 
46.5 
47.0 
49.0 
54.5 
51.5 
57.0 
55.0 
55.5 
60.0 
55.5 
55.0 
56.0 
56.5 
64.0 
64.0 
66.5 
66.0 
70.5 
70.5 
72.0 
72.0 
79.0 
