| dc.description.abstract | A behavioral bioassay method was developed to examine
the effects of ethanol on the reproductive success and
behavior of flagfish (Jordanella floridae). Reproductive
behavior was divided into eight categories; egg tending;
nesting; t-circling; chasing a faded female; spawning;
guarding; chasing; and inattentive behavior. The dominant
male in each tank was observed for ten minutes daily for
five days before and after ethanol exposure. The data was
examined to determine the frequency with which each behavior
occurred, the percent of the Total Frequency that each
behavior represented, the total time spent at each behavior, and the sequential order in which the behaviors occurred.
Total Frequency, the number of times the fish switched
from one behavior to another, was reduced when the fish were
exposed to concentrations of ethanol ranging from 0.5 to 3.0
g/liter. When behavior was analyzed with respect to the
eight behavioral categories, it was found that no single
behavior contributed to the decline but rather the number
of times a fish engaged in each behavior was reduced.
Accompanying this reduction in activity was an increase in
inattentive behavior. When sequences of behavior were
examined, no significant change occurred even at the higher
ethanol concentrations.
Fewer eggs were recovered from adults exposed to 2.0 and 3.0 g/liter. Of the eggs produced, hatchability and
larval survival exceeded 94% and 90%, respectively, at all
concentrations tested. It was concluded that the reduction
in spawning activities at concentrations of 1.5, 2.0, and
3.0 g/liter ethanol was due to the overall reduction in
activity. It appears that the dominant male must maintain
a minimal threshold of activity to successfully spawn. | |
