Abstract
The coastal fish assemblage in three protected sites and one unprotected area in the Slovenian part of the Gulf of Trieste (Northern Adriatic) was studied. Species composition and richness were comparable at all studied sites, including the control, unprotected area. Differences in fish density between the protected area of Debeli rtič and the unprotected area of Fiesa‐Pacug were revealed using correspondence analysis. Particularly the densities of certain labrid species ( Symphodus cinereus and S. roissali ) were higher in the protected area. Those differences are attributable to the extended and densely vegetated infralittoral belt of the Debeli rtič area rather than to its protected status.