It is established that estuarine ecosystems come with numerous ecological functions and societal benefits that are nowadays threatened by multiple local and global pressures more or less directly related to human activities. Such services are illustrated through the nursery function, essential for several fish stocks turnover. The main feature of an estuarine ecosystem is its highly variable environment ranging from daily oceanic tides and seasonal oxygen depletion to annual river flooding applying significant pressure to which are added anthropogenic ones upon the bentho-demersal fish communities of estuaries. Thus, in the French Atlantic coast, the Loire estuary faces a process of marinisation combining these both kinds of pressure: decrease in river flows and navigation channel digging that allow salty tide to reach always further upstream in the Loire bed. Studying how bentho-demersal fish communities respond to these pressures can contribute to a better understanding of the resilience of this ecosystem particularly in its nursery function. For this purpose, in reference to the 80s prior studies, a long-term series analysis was conducted. First ichthyological structural diversity patterns were determined at spatial and temporal scales in relation to environment drivers. Second, ecological trajectories were used to compare both spatial and temporal dynamics. Amongst estuarine environmental drivers tested, salinity range strongly drives the patterns observed with a tendency towards the more frequent penetration of marine species up to the lower reaches of estuary that have modified the previously-established bentho-demersal fish assemblage though alpha diversity did not show significant decrease. Such results indicate that marinisation induces modifications in the bentho-demersal estuarine community structure. They question about the consequence on nursery functioning. This matter will be addressed through a further functional approach on the carrying capacity for juvenile fish.