236 
Fishery Bulletin 1 13(3) 
The mean fork lengths of the 2 groups were similar 
(cultured: 22.3 cm [SD 1.0]; wild: 23.1 cm [SD 4.5]), 
but the range was greater for wild fish. However, even 
in an analysis where the sample of wild fish was lim- 
ited in relation to fish in the narrower size 
range of cultured fish (20-24 cm FL), the 
wild fish still persisted in the nursery sig- 
nificantly longer than cultured fish (MW: 
Z=-2.6, P<0.01). Comparison of the body 
lengths of all wild fish according to time 
spent in the nursery showed that bigger 
fish left sooner (coefficient of correlation, 
r=-0.39, n= 28, P<0.05). 
Light and temperature 
The tidally driven cycle of bottom 
temperature in the nursery is an- 
other variable that potentially could 
influence fish behavior. Prior work 
has shown that high tides pushed 
a cooler, bottom-associated lens of 
water (~2°C colder) into the nursery 
(Moffitt and Parrish, 1996). Our data 
loggers on the bottom confirmed this 
tidal influx of cold water for both 
years with the temperature cycle 
ranging between 22.0°C and 25.5°C 
(Fig. 4). This prominent environmen- 
tal feature is present interannually, 
but the cyclical change in tempera- 
ture did not appear to control the 
behavior of the fish in our study. 
Tag detections indicate that 4 of the 
wild crimson jobfish (18-22 cm FL) 
stayed at the nursery for multiple 
weeks, and, during that time, they 
showed no behavioral change attrib- 
utable to the temperature cycle (Fig. 
5). One of those wild fish (tag 1835) 
moved from the range of one receiver 
on the terrace to the other receiver 
and then adopted a pattern of being 
present during the day and absent at 
night. Movements of the other 3 fish (tags 1834, 1850, 
and 1844) showed that they remained continuously 
within the range of detection for large portions of the 
period regardless of changes in temperature. 
The wild fish lingered in the nursery for 3 
days after release, and documented move- 
ments indicate a bimodal pattern of higher 
numbers of the wild fish in the nursery dur- 
ing the day than during the night, indicat- 
ing that the fish were diurnally active (Fig. 
3). The inflection point in the pattern of data 
for high and low fish numbers was most ob- 
vious around dawn and dusk and the larger 
daytime numbers were statistically signifi- 
cant (ANOVA: F= 23.7, PcO.OOl). In the eve- 
ning, when detections in the nursery were 
lower, there was no corresponding increase 
in the number of fish detected at the re- 
ceivers on the slope adjacent to the nursery 
(t=- 0.57, P= 0.572) 
0 ) 
-Q 
E 
Hours since release 
Figure 3 
Bimodal pattern in the numbers of wild juvenile crimson jobfish 
(Pristipomoides filamentosus ) detected by hour for the first 3 days 
after release in 2007 of fish in the nursery offshore of Kaneohe Bay, 
windward Oahu. The gray bars represent hours of night. 
