Condition of 0-group and adult pouting, Trisopterus luscus L., along the Portuguese coast: evidence of habitat quality and latitudinal trends

The present study assessed condition of pouting ( Trisopterus luscus Linnaeus, 1758) in nursery areas and other coastal areas along the Portuguese coast using different indices. Condition factor Fulton's K, RNA : DNA ratio and total protein content were determined for 0-group pouting collected in three shallow nursery grounds. Adult pouting were sampled in 10 sites along the coast and Fulton's K, hepatosomatic index (HSI), total protein content and water content were determined as indicators of condition. For 0-group individuals, only total protein content showed significant differences among the sites, whereas in adults all the indices evaluated differed significantly among the sites. However, due to high RNA : DNA ratios it was considered that all investigated nursery areas provided suitable conditions for survival and rapid growth of early stages of T. luscus . Adult pouting were also considered to be in good physical and nutritional condition along the Portuguese coast, although better growth conditions seem to be provided in the warmer waters of southern Portugal, evidencing a latitudinal trend.