27 
NOAA 
National Marine 
Fisheries Service 
Abstract— Gray triggerfish ( Bati- 
stes capriscus) sampled from rec- 
reational and commercial vessels 
along the southeastern coast of 
the United States in 1990-2012 
(n=6419) were aged by counting 
translucent bands on sectioned first 
dorsal spines. Analysis of type of 
spine edge (opaque or translucent) 
revealed that annuli formed during 
March-June, with a peak in April 
and May. Gray triggerfish were 
aged up to 15 years, and the larg- 
est fish measured 567 mm in fork 
length (FL). Weight-length relation- 
ships from a different set of sampled 
fish were ln(W)=2.98xln(FL)-17.5 
(n=20,431; coefficient of determi- 
nation [r 1 2 * * ]=0.86), In-transform fit; 
W=3.1xl0- 5 TL 2 - 88 (n=7618), direct 
nonlinear fit; and FL=30.33+0.79xTL 
(77=8065; r 2 =0.84), where W=whole 
weight in grams, FL=fork length in 
millimeters, and TL=total length in 
millimeters. Mean observed sizes at 
ages 1, 3, 5, 10, and 15 years were 
305, 353, 391, 464, and 467 mm 
FL, respectively. The von Berta- 
lanffy growth equation for gray trig- 
gerfish was L t = 457 ( l-e ( “°- 33u+1 ' 58,) ). 
Natural mortality (M) estimated by 
Hewitt and Hoenig’s longevity-based 
method that integrates all ages was 
0.28. Age-specific M values, estimat- 
ed with the method of Charnov and 
others, were 0.65, 0.45, 0.38, 0.34, 
and 0.33 for ages 1, 3, 5, 10, and 15, 
respectively. Gray triggerfish recruit- 
ed fully to recreational fisheries by 
age 4 and to the commercial fishery 
by age 5. Estimates of total mortal- 
ity averaged 0.95 across all fisheries 
for the years 1986-2011. 
Manuscript submitted 2 August 2013. 
Manuscript accepted 17 November 2014. 
Fish. Bull. 113:27-39 (2015). 
doi: 10.7755/FB.113.1.3 
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 
Hr established 1881 ■<?. 
Spencer F. Baird 
First U S. Commissioner 
of Fisheries and founder 
of Fishery Bulletin 
Age, growth, and mortality of gray triggerfish 
iBalistes capriscus ) from the southeastern 
United States 
Michael L. Burton 
Jennifer C. Potts 
Daniel R. Carr 
Michael Cooper 
Jessica Lewis 
Email address for contact author: michael.burton@noaa.gov 
Beaufort Laboratory 
Southeast Fisheries Science Center 
National Marine Fisheries Sen/ice, NOAA 
101 Pivers Island Road 
Beaufort, North Carolina 28516-9722 
The gray triggerfish ( Batistes ca- 
priscus ) (family Balistidae) is widely 
distributed throughout the Atlantic, 
from Nova Scotia to Argentina and 
throughout the Gulf of Mexico in 
the western Atlantic (Briggs, 1958; 
in Moore, 1967) and, in the eastern 
Atlantic, from Ireland (Quigley et ah, 
1993) to southwestern Africa (Long- 
hurst and Pauly, 1987; Kortenang 
et ah, 1996), where tremendous in- 
creases in biomass have been ob- 
served for this species beginning in 
the late 1960s (Caveriviere, 1982; 
Ofori-Danson, 1989). Gray trigger- 
fish exhibit reproductive behavior 
that is benthic and nest-building 
(MacKichan and Szedlmayer, 2007; 
Simmons and Szedlmayer, 2012), 
and larvae and juveniles have been 
shown to use drifting mats of brown 
algae ( Sargassum spp. ) for habitat in 
the Gulf of Mexico (Wells and Hook- 
er, 2004) and off the Atlantic coast of 
the United States (Settle, 1993), gen- 
erally settling out of the pelagic zone 
to benthic habitats at age 0 and at a 
mean size of 96 mm in fork length 
(FL) in the fall (October) (Simmons 
and Szedlmayer, 2011). 
Gray triggerfish are of major im- 
portance to the commercial and 
recreational sectors of the fishery 
for reef fishes in the southeastern 
United States (SEUS). Within the 
recreational sector, estimated annual 
landings from headboats sampled by 
the Southeast Region Headboat Sur- 
vey (SRHS), which is administered 
by the Beaufort Laboratory of the 
Southeast Fisheries Science Center 
(SEFSC), National Marine Fisheries 
Service (NMFS), averaged 56 metric 
tons between 1986 and 2011 (Bren- 
nan 1 ). These landings have equated 
to an average ranking of sixth among 
the 73 species managed under the 
South Atlantic Fishery Management 
Council’s (SAFMC) Snapper-Grouper 
Fishery Management Plan. Esti- 
mated landings from private recre- 
ational boats and charter boats, the 
other component of the recreational 
sector, averaged 84.5 metric tons an- 
nually during 1986-2011 (Sminkey 2 ). 
Commercial fisheries of the SEUS 
harvested an average of 125.5 met- 
1 Brennan, K. 2013. Unpubl data. 
Southeast Fisheries Science Center, Na- 
tional Marine Fisheries Service, Beau- 
fort, NC 28516-9722. 
2 Sminkey, T. 2013. Unpubl. data. Na- 
tional Marine Fisheries Service, NOAA, 
Silver Spring, MD 20910. 
