The bogue, Boops boops (Linnaeus, 1758); large-eye dentex, Dentex macrophthalmus (Bloch, 1791); common two-banded seabream, Diplodus vulgaris (Geoffroy Saint-Hilaire, 1817); and axillary seabream, Pagellus acarne (Risso, 1827) are four commercially important sparid species which are distributed in the Mediterranean. Although they are very common in the Mediterranean, information regarding; growth, length at first maturity, and age are scarce and variable. This study provides some of the first data on the above-mentioned biological parameters of these four sparid species for the Turkish coasts of the Aegean Sea (Mediterranean). The aim of the present study is to expand our knowledge on the biology of these commercial sparid species from the Aegean Sea.

Fish samples were collected between July 2004 and June 2007 by R/V Egesüf from İzmir Bay. Demersal trawl samplings were carried out by a traditional trawl net with a 5 m codend (600 mesh circumference at the codend) and made of knotted polyethylene material with 40 mm mesh size netting.

The length–weight relations determined in the course of this study were: W = 0.005L3.25 (bogue), W = 0.005L3.03 (large-eye dentex), W = 0.007L3.31 (common two-banded seabream), and W = 0.009L3.14 (axillary seabream). The respective L¥ and k parameters of von Bertalanffy growth equation were: 29.58 and 0.266 for bogue; 24.3 and 0.399 for large-eye dentex; 28.0 and 0.253 for common two-banded seabream; and 22.7 and 0.315 for axillary seabream. Furthermore, lengths at first maturity were determined as: 12.96 (♀) and 9.35 (♂) cm for bogue; 10.83 (♀) and 11.77 (♂) cm for large-eye dentex; 12.87 (♀) and 13.37 (♂) cm for common two-banded seabream; and 14.45 (♀) and 13.91 (♂) cm for axillary seabream.

The presently determined parameters of age, growth, reproduction, and mortality of these four species will be useful for estimating the relevant parameters of population dynamics and will hopefully contribute to a better understanding of the long-term changes of the stock sizes.