103 
NOAA 
National Marine 
Fisheries Service 
Abstract— Passive acoustic recorders 
were used to monitor sound produc- 
tion indicative of the use of spawn- 
ing habitat by groupers (Serranidae) 
at Riley’s Hump, which is located in 
the Tortugas South Ecological Re- 
serve (TSER), part of the Florida 
Keys National Marine Sanctuary. 
Sound production by black grouper 
(Mycteroperca bonaci), red grouper 
( Epinephelus morio), and red hind 
( E . guttatus) was recorded year- 
round and at all times of day but 
occurred more often in the evening 
during the winter— spring spawning 
period than during other times of 
the day and year. This pattern for 
these species is consistent with re- 
sults of previous studies that docu- 
mented the association of sound pro- 
duction with reproductive behavior 
at spawning sites. Distinct diel and 
seasonal patterns of sound produc- 
tion by the longspine squirrelfish 
( Holocentrus rufus) and bicolor dam- 
selfish ( Stegastes partitus) also were 
recorded. Riley’s Hump is a docu- 
mented spawning site for mutton 
snapper ( Lutjanus analis), and re- 
cordings of black grouper, red grou- 
per, and red hind indicate that it is 
used for reproductive purposes by 
these species as well. These results 
showed the importance of the TSER 
and the need for continued research 
to understand its role in the recov- 
ery and sustainability of managed 
fish populations. 
Manuscript submitted 7 May 2015. 
Manuscript accepted 23 November 2015. 
Fish. Bull. 114:103-116 (2016). 
Online publication date: 10 December 2015. 
doi: 10.7755FB.114.1.9 
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. 
Fishery Bulletin 
established 1881 -c=. 
Spencer F. Baird 
First U S. Commissioner 
of Fisheries and founder 
of Fishery Bulletin 
A passive acoustic survey of fish sound 
production at Riley's Hump within Tortugas 
South Ecological Reserve: implications 
regarding spawning and habitat use 
James V. Locascio 1 (contact author) 
Michael L. Burton 2 
Email address: locascio@mote.org 
1 Mote Marine Laboratory 
1600 Ken Thompson Parkway 
Sarasota, Florida 34236 
2 Beaufort Laboratory 
Southeast Fisheries Science Center 
National Marine Fisheries Service, NOAA 
101 Pivers Island Road 
Beaufort, North Carolina 28516-9722 
Because most large groupers support 
large commercial and recreational 
fisheries, there is an increasing focus 
on the conservation and management 
of their stocks and habitats. Funda- 
mental to management decisions 
about these species is information 
on trends in population abundance 
and distribution, life history, and 
habitat use. Data that are used to 
understand these topics typically are 
generated from long-term time series 
based on visual surveys by divers, 
active acoustic surveys, mark and 
recapture studies, or subsampling of 
commercial catches. Recognition and 
protection of critical habitat, both es- 
sential for the sustainability of grou- 
pers and other reef fishes, have been 
realized through the establishment of 
marine protected areas and reserves 
(Roberts et al., 2005). An important 
consideration when selecting a loca- 
tion for a marine reserve is whether 
the area is used as a spawning ag- 
gregation site (Koenig et al., 2000). 
In many cases, fish spawning ag- 
gregation sites were first discovered 
by commercial fisherman and later 
established as marine reserves when 
their conservation value was under- 
stood. Such sites become prime lo- 
cations for implementing long-term 
field studies to evaluate the efficacy 
of reserves for population recovery 
and to learn more about the behavior 
and dynamics of spawning aggrega- 
tions (Burton et al., 2005). 
Groupers, as the name implies, 
form seasonal spawning aggregations 
at traditional sites. The structure 
and size of these aggregations vary 
by species and may directly influence 
their vulnerability to overfishing. For 
example, Nassau grouper ( Epineph- 
elus striatus) and red hind ( E . gut- 
tatus) form few, large aggregations 
(Whaylen et al., 2004; Kadison et al., 
2009), a characteristic that increases 
their risk to recruitment overfishing. 
Because of this vulnerability, it has 
been important to consider spawning 
locations of red hind in the establish- 
ment of marine protected areas and 
seasonal closures in the U.S. Carib- 
bean (Nemeth, 2012). Evidence from 
Belize indicates that black grouper 
( Mycteroperca bonaci) form numer- 
ous medium-size aggregations (<200 
individuals) at various locations 
