Expanding Habitat Use and Behavioural Shifts in the Recovering Population of the Mediterranean Monk Seal ( Monachus monachus )

ABSTRACT

The Mediterranean monk seal ( Monachus monachus ) remains one of the rarest marine mammals globally, with Greece constituting a principal population stronghold in the Mediterranean Sea. This study examines long‐term trends in distribution, habitat use, behaviour and responses to human presence using 8.105 citizen‐science records collected between 1990 and 2024 through the Hellenic Mediterranean Monk Seal Rescue and Information Network. Live sightings increased significantly at the national scale, while mortality records remained stable, supporting evidence of population recovery. Regional trends were heterogeneous, with strong increases in the Ionian–Adriatic and North Aegean, moderate growth in the Central Aegean and limited recovery in the South Aegean–Levantine. Seasonal occurrence increases in both warm and cold periods, peaking in summer and autumn. Marine caves remained the core terrestrial habitat of the species, with increasing observations of resting, sleeping, swimming and nursing. Simultaneously, growing use of open beaches and areas near human settlements indicates expanding habitat breadth. Behavioural analyses revealed strong habitat–activity correlations and a shift towards predominantly neutral or alert responses to humans, suggesting increasing tolerance of human presence. These findings highlight enhanced behavioural plasticity under changing ecological and demographic conditions. As recovery advances, behavioural shifts and habitat expansion must be explicitly incorporated into adaptive conservation planning, particularly in regions where recovery remains limited.