324 
National Marine 
Fisheries Service 
NOAA 
Fishery Bulletin 
é> established in 1881 «<= 
Spencer F. Baird 
First U.S. Commissioner 
of Fisheries and founder 
of Fishery Bulletin 
Abstract—The stone scorpionfish (Scor- 
paena mystes) is common throughout 
the Gulf of California in Mexico. Because 
little information is available regard- 
ing the basic biological characteristics 
of this species and because commercial 
demand for it is increasing, the need 
for studies of population dynamics is 
urgent. We sampled 233 stone scorpi- 
onfish (117 males and 116 females) in 
the Gulf of California from May 2015 
through April 2016 to estimate age and 
individual growth. Total lengths (TL) 
ranged between 15.3 and 35.5 cm for 
males and between 19.0 and 44.5 cm 
for females. Results from analysis of 
the edge types of otoliths (opaque and 
translucent) indicate an annual period- 
icity in the formation of annuli in sagit- 
tae. Ages of stone scorpionfish ranged 
from 2 to 10 years for males and from 
3 to 15 years for females. Estimates 
for the parameters of the von Berta- 
lanffy growth function were 34.76 and 
48.22 cm TL for asymptotic length, 
0.202/year and 0.135/year for growth 
coefficient, and -1.28 and —0.80 years 
for theoretical age at length zero for 
males and females, respectively. This 
study resulted in the first estimates 
of age and individual growth of stone 
scorpionfish, information that is essen- 
tial for evaluation and management of 
this important fishery resource. 
Manuscript submitted 14 May 2020. 
Manuscript accepted 15 October 2020. 
Fish. Bull. 118:324-328 (2020). 
Online publication date: 29 October 2020. 
doi: 10.7755/FB.118.4.2 
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. 
Age and growth of stone scorpionfish 
(Scorpaena mystes) from the Gulf of 
California in Mexico 
Ulianov Jakes-Cota (contact author)' 
Arturo Tripp-Valdez' 
Marisol Arce-Acosta' 
Francisco Omar Lépez-Fuerte” 
Email address for contact author: ujakesc@gmail.com 
' Departamento de Pesquerias y Biologia Marina 
Centro Interdisciplinario de Ciencias Marinas 
Instituto Politécnico Nacional 
Avenida Instituto Politécnico Nacional s/n 
Colonia Playa Palo de Santa Rita 
Apartado Postal 592 
23096 La Paz, Baja California Sur, Mexico 
The stone scorpionfish (Scorpaena mys- 
tes) is commonly found throughout the 
Gulf of California in Mexico, with a dis- 
tribution in the eastern Pacific Ocean 
that extends from southern California to 
Chile, including offshore islands (Butler 
et al., 2012). This demersal species occurs 
in shallow waters and seaweed-covered 
reefs as well as in open, sandy areas to 
depths of 85 m. It is considered an oppor- 
tunistic predator and feeds mainly on 
crustaceans and small fish (Butler et al., 
2012). Adults reach sizes up to 51 cm in 
total length (TL) (Robertson and Allen, 
2015). 
The meat of stone scorpionfish is 
considered to be of excellent quality 
and has high commercial value; as 
a result, this species has become an 
important fishery resource (Jakes-Cota 
et al., 2017). Historically, however, 
this species has not been sought after 
commercially because venom glands 
located along the spines of the fins 
can cause painful injuries and severe 
respiratory disorders (Poss, 1995); it 
has long been a secondary priority spe- 
cies in the artisanal fishery in the Gulf 
of California. Since 2012, decreases in 
* Laboratorio de Sistemas Arrecifales 
Departamento Académico de Ciencias 
Marinas y Costeras 
Universidad Aut6noma de Baja California Sur 
Carretera al Sur km 5.5 
23080 La Paz, Baja California Sur, Mexico 
the catches of other species of high 
commercial value, such as the Pacific 
red snapper (Lutjanus peru) and yel- 
lowtail jack (Seriola lalandi), caused 
an increase in price and capture vol- 
ume of the stone scorpionfish, driving 
this species into the commercial sec- 
tor as a complementary, high-quality 
product. 
Given the little amount of data avail- 
able on the basic biological characteris- 
tics of this species and its recent 
commercial exploitation in the region 
of the Gulf of California, there is an 
urgent need to document its basic life 
history (e.g., age, growth, mortality, 
and reproduction) and its population 
dynamics and to create a management 
protocol for this fishery resource. Age 
and individual growth should be 
included as key elements in every 
investigation focused on the rational 
exploitation of fishing resources 
(Beamish and Fournier, 1981). Prior to 
this study, the age and individual 
growth characteristics of stone scorpi- 
onfish were not available; therefore, 
the aims of our study were 1) to esti- 
mate age by using otoliths, 2) to 
