A new fish species has been recorded in Maltese waters by Patrick Vella and Alan Deidun.
The female species of the new fish record was caught by means of a trammel net on Munxar Reef, off St Thomas Bay, along the southeast coast of Malta.
While such new records are becoming quite common, the latest find has added significance in that it is also a new record for the Mediterranean Sea, Dr Deidun said.
The African moonfish (Selene dorsalis) species in question is a native of the tropical and subtropical waters of the eastern Atlantic, from the Cape Verde islands and Senegal to South Africa, where it is a popular commercial fish species. It belongs to the fish family Carangidae, which includes also jacks, scads and jack mackerels. The species generally forms schools, is carnivorous (feeding on small crustaceans and other fish) and is found within a depth range of 20-100 metres.
Prior to this first sighting in the Mediterranean, the fish species, also known by the common names of African lookdown or pompano, was previously recorded in the coastal waters off the Canary Islands and in the Gulf of Cadiz just outside the Straits of Gibraltar, along the Spanish coast. This might suggest, Dr Deidun explained, a northward range expansion of the species, possibly due to the warming trend of surface waters within the Mediterranean Basin.
The recorded species probably entered the Mediterranean Sea from the Atlantic Ocean rather than from the Red Sea. The mooted "tropicalisation" of the Mediterranean Sea in recent years, the increased maritime traffic and the opening of the Suez Canal, has spearheaded the invasion of the Mediterranean Sea by non-indigenous species, mainly of Lessepsian (Red Sea and Indian Ocean) origin.
The recording of a single species does not constitute the establishment of a viable population within the Mediterranean Sea and the record by Mr Vella and Dr Deidun must therefore be confirmed through at least two other separate sightings within the Basin before the species is included in the International Commission for the Scientific Exploration of the Mediterranean Sea's list of exotic fish species. There are over 700 species of non-indigenous types of fauna and flora officially recorded from the Mediterranean Sea.
The specimen was caught by fisherman R. Ghiller and was identified by Patrick J. Schembri and Titian Schembri from the Department of Biology of the University of Malta.
The details of the finding have just been published in a scientific paper included in the online journal JMBA 2 (Journal of the Marine Biological Association) of the UK. The full text of the paper is available at www.mba.ac.uk/jmba/pdf/6428.pdf.