Relationships between fish size and otolith measurements for 33 fish species caught by bottom trawl in Haizhou Bay, China

Abstract

Information from otoliths, together with data such as fish length and growth, can be a useful tool for population identification, aging, and feeding studies as well as stock assessments (Harvey et al., 2000; H€ ussy et al., 2010; Jawad et al., 2011). Since Trout (1954) and Templemann and Squires (1956) studied the relationship between cod size and otolith measurements, relationships between fish size and otolith dimensions have been explored for many species (Jawad et al., 2012). For example, Steward et al. (2009) used the relationship between fish length and otolith dimensions to predict age in gray angelfish, and Ag€ uera and Brophy (2011) used otolith shape analysis for the discrimination of Atlantic saury stocks. Haizhou Bay is an open bay on the western margin of the southern Yellow Sea and historically an important fishing ground. The bay still serves as a critical spawning and nursery habitat for many commercial fish species, such as Larimichthys polyactis, Setipinna taty and Engraulis japonicas (Editorial Board of Annals of Bays in China, 1993). The relationship between fish length and otolith dimensions can be described by using a simple linear regression (Harvey et al., 2000; Jawad and Al-Mamry, 2012), but these relationships between fish size and their otolith dimensions are lacking in the literature for species living in the Haizhou Bay. The objective of this study was to determine the relationships between fish length and otolith dimensions (otolith length, width, long radius and short radius) using simple linear regression for 33 species in Haizhou Bay. These results can provide a foundation for further research on these species, which may require knowledge of these relationships.