Biochemical composition and somatic growth of pelagic larvae of three fish species from the Bay of Biscay

The growth strategies of pelagic larvae of 3 fish species from the Bay of Biscay belonging to 2 different shape groups, the eel-like anchovy Engraulis encrasicolus and sardine Sardina pilchardus, and the tadpole-like horse mackerel Trachurus trachurus, are compared in terms of changes in their biochemical composition and energy allocation. In anchovy and sardine, the relative amount of protein increased and relative amounts of carbohydrates and lipids decreased throughout their growth. The biochemical composition in horse mackerel did not change significantly during growth. Differences between the 2 shape groups could be associated with the various energy allocation patterns related to dissimilar growth strategies. Although the patterns of change in biochemical composition during growth are different in the 2 shape groups, they show a very similar biochemical composition at the notochord flexion stage, indicating convergences in life-history patterns of the different species.