Bradbury et al.: Daily and seasonal activity patterns of female Tautogolabrus adspersus 
649 
Table 3 
Results of the Wilcoxon matched-pairs signed-ranks test (t-value) used to compare interindividual differences in activity between 
pairs of cunners tracked during the same periods (n represents the number of days during which comparisons were made). 
Critical values of t are derived from Rohlf and Sokal (1969). There were no significant differences between fish for any of the 
activity parameters tested. 
Comparisons between fish A and fish B Comparison between fish C and fish D 
Behavioral parameter 
n 
t-value 
Critical t-value 
(significance level) 
n 
t-value 
Critical <-value 
(significance level) 
Percent of time inactive 
n 
26 
13 (0.0415) 
14 (0.0508) 
9 
11 
8 (0.0488) 
9 (0.0645) 
Length of inactivity bout 
ii 
26 
13 (0.0415) 
14 (0.0508) 
9 
14 
8 (0.0488) 
9(0.0645) 
Onset of activity 
9 
15 
8 (0.0488) 
9 (0.0645) 
7 
6 
3 (0.0391) 
4 (0.0547) 
Cessation of activity 
8 
10 
5 (0.0391) 
6 (0.0547) 
7 
5 
3 (0.0391) 
4(0.0547) 
Duration of diurnal activity 
8 
13 
5 (0.0391) 
6 (0.0547) 
7 
7 
3 (0.0391) 
4 (0.0547) 
Table 4 
Summary of multiple regression analysis on the effects of time of day (prior to 1200 h vs. after 1200 h), date, and environmental 
variables on activity of female cunner. A minimum of 62 days and a maximum of 89 days were incorporated in the regression 
analysis for the last three behavioral parameters. Percentage of variation accounted for by each variable is given. * = significant 
at 0.05 level; ** = significant at 0.01 level; and *** = significant at 0.001 level. 
Water 
Time of temperature Combined 
Behavioral parameter 
n 
day 
Date 
>5°C 
Sea state 
Cloud cover 
variables 
Percent of time inactive 
205 
0.6 
58.7*** 
0.2 
0.3 
0.1 
59.9*** 
Length of inactivity bout 
229 
0.1 
12 7*** 
2.8** 
1.7* 
0.2 
17.5*** 
Onset of activity 
75 
NA 
6.6* 
1.9 
0.0 
0.1 
8.6 
Cessation of activity 
83 
NA 
22.3*** 
0.2 
0.0 
0.5 
23.0*** 
Duration of diurnal activity 
62 
NA 
92.3*** 
0.9** 
0.1 
0.1 
93.4*** 
again dropped to 3°C, resulting in cunners being in- 
active for the remainder of the day. Temperatures 
above 5°C had small but significant effects on length 
of inactivity bouts and duration of diurnal activity 
(Table 4). Length of bouts of inactivity tended to de- 
crease with increasing water temperature, whereas 
the trend was reversed for the duration of diurnal 
activity. Water temperatures above 5°C had no sig- 
nificant effect on the onset or cessation of activity or 
on the percentage of time spent inactive. 
Sea state had a significant (P<0.05) effect on length 
of cunner inactivity bouts (Table 4), with bouts of 
inactivity tending to be longer on days with high 
surface waves. Sea state did not have a significant 
effect on other activity parameters. Cloud cover had 
no significant effect on any of the activity param- 
eters. There was a trend, however, for females to re- 
main inactive for longer periods (i.e. percentage of 
time spent inactive increased as well as length of 
inactivity bouts) as cloud cover increased. There was 
also a tendency for the duration of diurnal activity 
to decrease with increasing cloud cover. Neither per- 
centage of diurnal activity period spent inactive or 
length of inactivity bouts differed between morning 
and afternoon (Table 4). 
There was no significant difference in fish behav- 
ior owing to tides (Table 5), indicating that both fish 
A and fish B responded similarly to the tidal cycle. 
Furthermore, there was no significant difference in 
activity (i.e. percentage of time spent inactive) be- 
tween the various tidal phases for fish A or fish B 
(Table 5). Finally, there were no significant differ- 
