Trophic ecology of Sardina pilchardus and Engraulis encrasicolus was examined and compared among various regions of Mediterranean Sea.

The δ¹³C and δ¹⁵N were adopted as a tool to determine changes in feeding behaviour of adults of sardines and anchovies.

A clear geographical pattern was recognized in the isotopic composition of both species, with an increasing trend northward.

Findings will improve fish stock management and promoting plans able to take into account also local ecosystem analysis.