Keywords
pleuston
jellyfish strandings
wind-driven circulation
multiplatform approach
teleconnection pattern
How to Cite
Funding data
-
NextGenerationEU
Grant numbers IR0000032;CUP B53C22002150006
Abstract
The Portuguese man-of-war, Physalia physalis (Linnaeus, 1758), is a pleustonic siphonophore distributed throughout tropical and subtropical oceans. Although the species is occasionally recorded in the Mediterranean Sea, its occurrence is generally linked to episodic advection driven by winds and surface currents. Here, we report observations of P. physalis in the central Mediterranean between 6 February and 6 March 2026, coinciding with massive strandings of the pleustonic hydrozoan Velella velella. A negative North Atlantic Oscillation (NAO) phase likely facilitated Atlantic water inflow and eastward transport into the Mediterranean. A drifter trajectory from the southern Tyrrhenian Sea indicated temporary retention near the Lipari coast. These records likely indicate a transient influx of P. physalis, rather than a stable Mediterranean population.
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