Survival of juvenile white mullet Mugil curema (Mugilidae) in a coastal lagoon.

C Quiñonez -Velázquez,J R López -Olmos,C I Pérez -Quiñones

doi:10.37543/oceanides.v30i1.142

Abstract

The hatching date frequency distribution (HDFD) of juvenile white mullet (Mugil curema) sampledat monthly intervals in the coastal lagoon Ensenada de La Paz, B.C.S., México from May 1997 to May 1998 was reconstructed for different age intervals and corrected for differences in the accumulated mortality. The ratio of the HDFD at a given age to the HDFD at an earlier age was used as an index of the relative survival of juveniles grouped into 14-day hatch-date cohorts. The results show that the white mullet spawns during the whole year inBahía de La Paz, with the highest survival of larvae from October to February. Variations of the relative survival of the age groups were correlated significantly to the variations in growth. A fast growth resulted in high survival while a slow growth yielded low and high survival. The latter was observed when the juveniles used the lagoonafter 40-days-old, indicating that the area is used mainly as a refuge. The return to the coastal area can explain the decrease of juveniles older than 80 days in the lagoon.

Highlights

The white mullet Mugil curema (Valenciennes, 1836) is distributed on both coasts of the American continent
The hatching date frequency distribution (HDFD) of juvenile white mullet (Mugil curema) sampled at monthly intervals in the coastal lagoon Ensenada de La Paz, B.C.S., México from May 1997 to May 1998 was reconstructed for different age intervals and corrected for differences in the accumulated mortality
The objective of this study is to identify the favorable periods for growth and survival of the white mullet (Mugil curema) larvae captured in El Conchalito inlet, located within Ensenada de La Paz, from May 1997 to May 1998, based on the juvenile hatch dates frequency distribution (HDFD)

Summary

Introduction

The white mullet Mugil curema (Valenciennes, 1836) is distributed on both coasts of the American continent. Reproduction takes place off the coast and the juvenile enter estuaries and coastal lagoons following turbid gradients (Blaber, 1987; Trape et al, 2009). In Ensenada de La Paz, on the southwest coast of the Gulf of California (Fig. 1), the white mullet is a common species all year, showing a bimodal length distribution (González-Acosta, 1998) and suggesting two recruiting groups. Growth in this species is rapid, achieving 25-cm length in one year (Martin & Drewry, 1978). The daily deposition of the growth increments have since been described for many fish species (Wild & Foreman, 1980; Brothers & McFarland, 1981; Campana & Neilson, 1985; Jones, 1986; Stevenson & Campana, 1992). Radtke (1984) validated the deposition of daily growth increments in otoliths of the striped mullet (Mugil cephalus) and we assume that this is true for Mugil curema

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