117 
National Marine 
Fisheries Service 
NOAA 
Fishery Bulletin 
established in 1881 
Spencer F. Baird 
First U.S. Commissioner 
of Fisheries and founder 
of Fishery Bulletin 
Age^ gromtli^ and length-imeiglit relationship 
of roosterfish pectoraiis} in the 
eastern Pacific Ocean 
Abstract — -Growth of roosterfish 
{Nematistius pectoraiis) was estimat- 
ed by analyzing daily growth incre- 
ments of sagittal otoliths collected 
from individuals captured in Ei Goifo 
Duke, Costa Rica during 2013-2014 
and in southern Baja California Sur, 
Mexico during 2010-2015. Isometric 
growth was observed for all individ- 
uals and no significant differences 
were observed in the length-weight 
relationships between sexes or loca- 
tions. Age estimates ranged from 18 
d (0.05 years) to 545 d (1.5 years), 
although 26% of otoliths (57-133 
cm) were not legible because narrow 
daily grov#th increments were diffi- 
cult to differentiate in older fish. In- 
dividual growth parameters indicate 
that roosterfish grow at a rapid rate 
during the first year of life, reach- 
ing sizes of around 60-70 cm in fork 
length. Although future field valida- 
tion is necessary, the results of our 
study provide insight into the life 
history of this valuable resource of 
the eastern Pacific Ocean. 
Manuscript submitted 11 March 2016. 
Manuscript accepted 30 November 2016. 
Fish. Bull. 115:117-124 (2017). 
Online publication date: 27 December 2016. 
doi: 10.7755/FB.115.1.10 
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. 
Sefia Ortega-Garda (contact author)' 
Chugey Sepulveda^ 
Scott Aalbers^ 
Uliano¥ Jakes-Cota' 
Ruben Rodriguez-Sanchei' 
Email address for contact author: sortega@ipn.mx 
' Instituto Politecnico Nadonai 
Centro Interdisciplinario de Ciencias Marinas 
Avenida Instituto Politecnico Nacional s/n 
Colonia Playa Paio de Santa Rita 
C.P. 23096 La Paz, Baja California Sur, Mexico 
^ Pfieger Institute of Environmental Research 
21 10 South Coast Highway 
Oceanside, California 92054 
A game fish that inhabits the neritic 
waters of the subtropical and tropical 
eastern Pacific Ocean (Eschmeyer et 
al., 1983), the roosterfish {Nematis- 
tius pectoraiis) is the only species 
in the genus Nematistius (family 
Nematistiidae). The most notable ex- 
ternal feature of this species is the 
presence of 7 elongated dorsal spines, 
which give rise to its common name 
(Rosenblatt and Bell, 1976) and al- 
lows it to be easily distinguished 
from other species (Mem, 1995). 
The roosterfish is a coastal species 
that has been found to occur in the 
Pacific Ocean from San Clemente, 
Southern California to San Lorenzo 
Island, Peru, including the Gulf of 
California and the Galapagos Islands 
(Love et al., 2005). Results from work 
to date indicate that roosterfish re- 
side primarily in warm (23-3 1°C), 
shallow waters where they may 
spend up to 90% of their time be- 
tween the sea surface and a depth 
of 12 m (Sepulveda et al., 2015). All 
age classes are considered neritic; 
juveniles are often found along the 
shoreline and larger individuals are 
commonly associated with both the 
surf line and complex near shore 
habitats (i.e., reefs and sand bars) 
(Niem, 1995; Sepulveda et al., 2015). 
Roosterfish can attain sizes up to 
191 cm in total length and more than 
51.7 kg (Robertson and Allen, 2015). 
They are active predators that have 
been reported to feed in shallow wa- 
ters (i.e., depths of 3-4 m) on school- 
ing fish species, such as species of 
mojarra (i.e., Pacific spotfin mojarra 
[Eucinostomus dowii] and graceful 
mojarra [E. gracilis}), and species 
of anchovy (i.e., sharpnose anchovy 
[Anchoa ischana} and Anchoa spp.) 
(Hobson, 1968; Rodriguez-Romero et 
al., 2009). 
The roosterfish is a very impor- 
tant resource for sportfishing indus- 
tries, especially for those that oper- 
ate at destinations favored by eeo- 
tourists, such as Baja California Sur, 
mainland Mexico, and the coast of 
Central America. Roosterfish contrib- 
ute significantly to the local economy 
because it is a common target of in- 
shore anglers; in fact, this species is 
sought out among anglers around the 
