327 
Diel and seasonal timing of sound production 
by black drum ( Pogonias cromis ) 
College of Marine Science 
University of South Florida 
140 Seventh Avenue South 
St. Petersburg, Florida 33701 
Email address for contact author: |locasci@mail. usf.edu 
Abstract — Acoustic recorders were 
used to document black drum ( Pogo- 
nias cromis) sound production during 
their spawning season in southwest 
Florida. Diel patterns of sound pro- 
duction were similar to those of other 
sciaenid fishes and demonstrated 
increased sound levels from the 
late afternoon to early evening — a 
period that lasted up to 12 hours 
during peak season. Peak sound 
production occurred from January 
through March when water temper- 
atures were between 18° and 22°C. 
Seasonal trends in sound produc- 
tion matched patterns of black drum 
reproductive readiness and spawning 
reported previously for populations 
in the Gulf of Mexico. Total acoustic 
energy of nightly chorus events was 
estimated by integration of the sound 
pressure amplitude with duration 
above a threshold based on daytime 
background levels. Maximum chorus 
sound level was highly correlated with 
total acoustic energy and was used to 
quantitatively represent nightly black 
drum sound production. This study 
gives evidence that long-term passive 
acoustic recordings can provide infor- 
mation on the timing and location 
of black drum reproductive behavior 
that is similar to that provided by 
traditional, more costly methods. The 
methods and results have broad appli- 
cation for the study of many other 
fish species, including commercially 
and recreationally valuable reef fishes 
that produce sound in association with 
reproductive behavior. 
Manuscript submitted 5 January 2011. 
Manuscript accepted 16 May 2011. 
Fish. Bull. 109:327-338 (2011). 
The views and opinions expressed 
or implied in this article are those of the 
author (or authors) and do not necessarily 
reflect the position of the National Marine 
Fisheries Service, NOAA. 
James V. Locascio (contact author) 
David A. Mann 
Knowledge of the timing and location 
of spawning provides fundamentally 
important information for the man- 
agement of fish species. Traditional 
methods for acquiring this knowl- 
edge have entailed 1) the collection 
of fishes for examination of spawning 
condition by means of gonad histology 
and gonadosomatic indices and 2) the 
calculation of the time of spawning 
by back-calculation from the ages of 
eggs or larvae at the time of collection 
(Peters and McMichael, 1990; Nieland 
and Wilson, 1993; Fitzhugh et al., 
1993). In some cases direct observa- 
tions of spawning have been made at 
fish aggregation sites with the use 
of scuba, remote cameras, and sub- 
mersible vehicles (Domeier and Colin, 
1997; Erisman and Konotchick, 2009). 
Although effective, these methods are 
labor intensive, costly, and not neces- 
sarily practical for providing high-res- 
olution data over an entire spawning 
season or synoptically at multiple sites 
within a season. 
Many fishes produce sounds associ- 
ated with reproductive behavior, and 
hydrophone recordings used to docu- 
ment this behavior have been con- 
ducted for many years (Breder, 1968; 
Gilmore, 2003; Mann et al., 2008). 
Relatively recent advances in technol- 
ogy have made low-cost submersible 
acoustic recording systems available 
for recording high-resolution acoustic 
data over long time periods. These 
recording systems, along with signal 
processing algorithms, now represent 
the most practical method available 
to collect long-term, high-resolution 
data on spawning behavior of sonif- 
erous fishes, many of which include 
commercially and recreationally man- 
aged species (i.e., drums and groupers 
[families Sciaenidae and Serranidae, 
respectively]). Such data can be col- 
lected synoptically over wide spatial 
scales and in remote environments 
that may not be accessible with other 
gear types. When acoustic data are 
combined with environmental data 
collected on similar time scales, a 
great deal can be learned about the 
ecology of sound production and the 
environmental requirements associ- 
ated with spawning site selection and 
spawning behaviors of fishes. 
The black drum is a large, long- 
lived sciaenid that ranges from the 
Bay of Fundy to Argentina (Hoese 
and Moore, 1998; Sutter et al. 1 ). In 
the Gulf of Mexico black drum spawn 
in bays and estuarine habitats from 
late fall through early spring (Mur- 
phy and Taylor, 1989; Peters and 
McMichael, 1990) and produce high 
intensity sounds associated with 
courtship and spawning (Mok and 
Gilmore, 1983; Saucier and Baltz, 
1993; Tellechea et al., 2010) that may 
exceed 170 dB re: IpPa (Locascio, 
2010). In this study our main objec- 
tives were to record and describe pat- 
terns of black drum sound production 
during the spawning season and to 
compare these data to previous data 
collected with traditional methods 
to document the spawning season of 
black drum. 
1 Sutter, F. C„ R. S. Waller, and T. D. Mcll- 
wain. 1986. Species profiles: life his- 
tories and environmental requirements 
of coastal fisheries and invertebrates 
(Gulf of Mexico) — black drum. U.S. 
Fish. Wildl. Serv. Bio. Rep. 82(11.51, 
U.S. Army Corps of Eng. TR EL82-4), 
10 p. 
