Comportamiento alimenticio y ración diaria de la solleta Citharus linguatula (Osteichthyes: Pleuronectiformes) en el mar Tirreno Central

Spotted flounder Citharus linguatula (Linnaeus, 1758) is one of the most abundant species within demersal fish assemblages next to the continental shelf (up to 200 m depth) of the Mediterranean Sea. In spite of the ecological importance of this species in the central Tyrrhenian Sea, many aspects of its biology (e.g. feeding behaviour) are poorly described. In order to analyze how feeding habits are related to the ontogenetic changes in this species, 2636 specimens (between 9 and 26 cm of total length TL) were collected from November 2000 to January 2002. During ontogenetic development spotted flounder occupied different trophic levels: diet shifted from mysids, predominantly in the smaller spotted flounder ( 19 cm TL). Before the transition to the icthyophagous phase, a more generalist foraging behaviour including decapods (Processa sp., Alpheus glaber), molluscs (Turitella sp.) and benthic fish (Lesuerigobius spp., Gobius niger, Callionymus spp., Arnoglossus laterna) dominated the diet. Seasonal analysis of the diet showed an increase in the presence of mysids in summer and autumn, and of decapods in summer and spring. Teleosteans are present throughout the year without significant variations. Daily ration values, computed from the Eggers method, ranged from 1.57% to 2.83% wet body weight, showing a negative relationship between reproduction and daily consumption rate.La solleta, Citharus linguatula, es una de las especies más abundantes entre las comunidades de peces de la plataforma continental (hasta los 200 m de profundidad) del Mediterráneo. A pesar de su importancia ecológica en el mar Tirreno central, muchos aspectos de la biología de C. linguatula (e.g. alimentación) continúan siendo desconocidos. Con el objetivo de investigar cómo los hábitos alimenticios están relacionados con los cambios ontogénicos en esta especie, se analizaron 2636 individuos, entre 9 y 26 cm de longitud total (LT), que fueron muestreados entre noviembre de 2000 y enero de 2002. Durante el desarrollo ontogénico C. linguatula ocupa diferentes niveles tróficos: la alimentación varía desde los misidáceos, que son predominantes para las solletas más pequeñas ( 19 cm LT). Antes de llegar a la fase piscívora, el régimen alimenticio es más generalista, incluyendo crustáceos decápodos (Processa sp., Alpheus glaber), moluscos (Turitella sp.) y peces bentónicos (Lesueurigobius spp., Gobius niger, Callionymus spp., Arnoglossus laterna). Los análisis estacionales de la dieta muestran un aumento de la presencia de misidáceos en verano y otoño, y un aumento de decápodos en verano y primavera. Los teleósteos están presentes todo el año sin ninguna variación significativa. Las valores de la tasa diaria de alimentación, calculados con el método de Eggers, variaron entre 1.57% y 2.83% del peso húmedo individual, con una relación negativa entre la reproducción y el consumo diario

Feeding behaviour and daily ration of the spotted flounder <i>Citharus linguatula</i> (Osteichthyes: Pleuronectiformes) in the central Tyrrhenian Sea

Spotted flounder Citharus linguatula (Linnaeus, 1758) is one of the most abundant species within demersal fish assemblages next to the continental shelf (up to 200 m depth) of the Mediterranean Sea. In spite of the ecological importance of this species in the central Tyrrhenian Sea, many aspects of its biology (e.g. feeding behaviour) are poorly described. In order to analyze how feeding habits are related to the ontogenetic changes in this species, 2636 specimens (between 9 and 26 cm of total length TL) were collected from November 2000 to January 2002. During ontogenetic development spotted flounder occupied different trophic levels: diet shifted from mysids, predominantly in the smaller spotted flounder ( 19 cm TL). Before the transition to the icthyophagous phase, a more generalist foraging behaviour including decapods (Processa sp., Alpheus glaber), molluscs (Turitella sp.) and benthic fish (Lesuerigobius spp., Gobius niger, Callionymus spp., Arnoglossus laterna) dominated the diet. Seasonal analysis of the diet showed an increase in the presence of mysids in summer and autumn, and of decapods in summer and spring. Teleosteans are present throughout the year without significant variations. Daily ration values, computed from the Eggers method, ranged from 1.57% to 2.83% wet body weight, showing a negative relationship between reproduction and daily consumption rate