The cornet fish (Fistularia commersonii) is considered by many as one of the most successful non-indigenous fish species to invade the Mediterranean Sea.

Since it first entered the Mediterranean in 2000, the species has been recorded in the south of Italy in 2004, in Tunisia in 2004, in the Tyrrhenian Sea in 2007 and in the Adriatic Sea and Ligurian Sea in 2008. In fact, no other such species has spread so far in the Mediterranean.

The species was first recorded in Malta in 2006 in a report in The Times when a single individual was caught in Xwejni Bay in Gozo. The species has been occasionally sighted in subsequent years.

A recent paper published in Biodiversity Journal by Alan Deidun and Alfio Germana reports a sharp increase in the cornet fish in Maltese and Sicilian coastal waters.

The species has been sighted or caught by a large number of Maltese and Sicilian scuba diving clubs and schools, fishermen and anglers. It has been sighted in Maltese waters at least 15 times over the past few months, while reports from Sicily hail from the four corners of the island.

The cornet fish individuals sighted ranged from 30 cm to 110 cm in length. The presence of both juvenile and adult individuals further confirms that the species has established viable populations in the central Mediterranean.

In addition, most of the sightings for the species reported in the study refer to small shoals rather than to single individuals, with most sightings being made in shallow water less than five metres deep characterised by a rocky seabed covered by seagrass.

The ongoing spread of exotic fish species and the general rearrangement of species’ geographical distribution are an increasing worldwide phenomenon and one of the most striking biological results of global climate change.