Abstract

SALGADO-CRUZ, Luis; QUINONEZ-VELAZQUEZ, Casimiro; GARCIA-DOMINGUEZ, Federico A.  and  PEREZ-QUINONEZ, Carlos I.. Detecting Mugil curema (Perciformes: Mugilidae) phenotypic stocks in La Paz Bay, Baja California Sur, Mexico, using geometric morphometrics of otolith shape, growth, and reproductive parameters. Rev. Mex. Biodiv. [online]. 2020, vol.91, e913273.  Epub Dec 22, 2020. ISSN 2007-8706.  https://doi.org/10.22201/ib.20078706e.2020.91.3273.

In a holistic approach it is important to identify potential fishing units to better understand population structure and dynamics. The objective of this work was to evaluate the potential existence of a Mugil curema population structured in stocks in La Paz Bay. For this, a total of 709 specimens were collected between 2010 and 2013. Two fish groups were identified (G1, n = 212, and G2, n = 178), and the otolith shape was compared using geometric morphometrics, L50% was estimated, age was assigned, and a multi-model approach was used to evaluate individual growth. Eight age groups were assigned for G1 (3-10) and 5 for G2 (3-7). The most adequate model to describe growth for both groups was the von Bertalanffy growth model (G1: L ∞ = 421.77, k= 0.32, t 0 = -0.05; G2: L ∞ = 406.5, k = 0.36, t 0 = -0.02). Differences in otolith shape and growth parameters between groups were significant; opposite, L50% estimates (G1 = 325 mm LT; G2 = 330 mm LT) were not significant. Results suggest the presence of a M. curema population structured in at least 2 stocks in La Paz Bay: one stock reproduces in Spring (G1) and the other in the Fall (G2).

Keywords : Population structure; Fishing stock; Multi-model approach; Individual growth; Reproductive pattern.