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Fishery Bulletin 1 14(1) 
Figure 8 
An example of sound production attributed to the bicolor damselfish (Stegastes partitus ) from the time se- 
ries of acoustic data recorded in the frequency range of 500-800 Hz at site RH2 at Riley’s Hump, Tortugas 
South Ecological Reserve, Florida Keys, in 2011. The seasonal period of sound production in this frequency 
range occurred from early spring through mid-summer. Sound pressure levels (SPLs) increased and de- 
creased gradually over a period of about 18 days, beginning near the new moon. Lunar symbols are defined 
as follows: new moon, •; first quarter, ©; full moon, O; and last quarter moon, 3 . 
duction in 2012 by these species could indicate that 
a longer spawning season occurred during that year 
and possibly also that a greater number of fishes were 
present. During 2012, both species demonstrated a 
preference for site RHDW, which was not monitored in 
2011 in our study. This site is located near the base of 
the steepest vertical relief of Riley’s Hump, a habitat 
feature of aggregation sites associated with relatively 
high densities of fishes (Kobara et al., 2013). 
The spawning season of the red grouper occurs ap- 
proximately from March through July in the Gulf of 
Mexico and peaks between March and June, although 
there is some variability with latitude. This timing is 
consistent with peak levels of sound production re- 
corded in this study. This species is not considered 
currently to be overfished or experiencing overfishing 
(Lowerre-Barbieri et al. 4 ). 
The spawning season of the black grouper is report- 
ed to occur from December through March in the Gulf 
of Mexico, although Crabtree and Bullock (1998), on 
the basis of gonad condition, suggested that spawning 
may occur year-round. The results of our study show 
that sound production of black grouper occurs year- 
round, but at levels higher from December through 
May than during other periods. The black grouper is 
4 Lowerre-Barbieri, S., L. Crabtree, T. S. Switzer, and R.H. Mc- 
Michael Jr. 2014. Maturity, sexual transition, and spawn- 
ing seasonality in the protogynous red grouper on the West 
Florida Shelf. Southeast Data Assessment and Review SE- 
DAR42-DW-07, 21 p. [Available at website.] 
not considered presently to be overfished or experienc- 
ing overfishing (SEDAR 5 ). 
Red hind in the U.S. Caribbean form spawning ag- 
gregations associated with various lunar phases from 
December through March (Mann et al., 2010; Nemeth, 
2012). In our study at Riley’s Hump, seasonal and 
lunar periods in sound production by red hind were 
similar to the periods observed in studies conducted 
in the U.S. Virgin Islands, although the timing of peak 
levels occurred 1-2 months later in the year at Riley’s 
Hump. Results of a stock assessment conducted during 
2013-2014 (SEDAR 6 ) indicate that the red hind is not 
overfished or experiencing overfishing in the U.S. Ca- 
ribbean, but this notion was not strongly conclusive on 
the basis of available data. 
Although most sound production by each grouper 
species reported here occurred during the winter and 
spring, calls also were recorded at other times of the 
year. It is difficult to conclude an alternative meaning 
for this finding without concurrent observations of be- 
havior, but one possibility may be that limited spawn- 
ing occurs during other times of the year. The black 
grouper, for example, has been reported to remain in 
sexually mature condition year-round (Crabtree and 
5 SEDAR (Southeast Data Assessment and Review). 2010. 
SEDAR 19 stock assessment report Gulf of Mexico and South 
Atlantic black grouper, 656 p. SEDAR, North Charleston, 
SC. [Available at website.] 
6 SEDAR (Southeast Data Assessment and Review). 2014. 
SEDAR 35 stock assessment report U.S. Caribbean red hind, 
350 p. SEDAR, North Charleston, SC. [Available at web- 
site.] 
