The cuckoo wrasse, &lt;i&gt;Labrus mixtus&lt;/i&gt; (Pisces: Labridae): biological indices for life history and conservation

Dubravka Bojanić Varezić,Pero Tutman,Jasna Šiljić,Armin Pallaoro,Sanja Matić-Skoko

doi:10.3989/scimar.03884.07a

Abstract

The cuckoo wrasse, Labrus mixtus, is widely distributed in the moderate warm waters of the Atlantic Ocean, including the Mediterranean and Adriatic Seas. Generally, labrids are small inshore coastal species susceptible to anthropogenic habitat degradation and, although without commercial importance, they make up a significant part of the by-catch and discard. Also, these fishes are intensively caught in recreational and subsistence fisheries. Basic biological information is required for their stock assessment and conservation. Studies of the age, growth, reproduction and feeding of L. mixtus have not been undertaken previously in the Adriatic Sea. The observed maximum age of the cuckoo wrasse was 10 years, although most of the sampled fish were 7 years old. The estimated parameters of the von Bertalanffy growth model suggested that the growth of L. mixtus was relatively fast in the first four years of life. L. mixtus is a protogynous hermaphrodite and sex change occurred at 26 cm, while the greatest increase in gonadosomatic index in April confirmed spring as the spawning period. The cuckoo wrasse is an opportunistic predator, feeding primarily on crustaceans, gastropods and fishes. The information provided on biological indices is necessary for life history pathways and future conservation measures of this population in the Adriatic Sea.

Highlights

The family Labridae contains 18 species native to the Adriatic Sea
Labrids are small inshore coastal species susceptible to anthropogenic habitat degradation and, without commercial importance, they make up a significant part of the by-catch and discard
Basic biological information is required for their stock assessment and conservation

Summary

Introduction

The family Labridae (wrasses) contains 18 species native to the Adriatic Sea. In terms of their habitat, Mediterranean wrasses are generally fairly shallowwater, demersal, inshore coastal species, generally sedentary in macroalga-dominated rocky reef habitats, but some occur in seagrass beds (Bell and HarmelinVivien 1982) and in coastal lagoons, and a few extend to deeper-water coralligenous habitats. To their small size, they are generally not heavily targeted They are intensively caught in recreational fisheries and they make up a significant percentage in the by-catch and discard of local artisanal and subsistence fisheries (Cetinić et al 2011, Tzanatos et al 2007). Such fisheries involve large numbers of people and high levels of fishing effort (Cowx 2002, Pitcher and Hollingworth 2002, Westera et al 2003). All of them suffer from relatively poor fisheries and conservation management, though most are included in some form of marine protection in the region (Jardas et al 2008)

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