Marine Biodiversity Research unravels new knowledge on puffer fish species

The majority of puffer fish species are toxic and some of the most poisonous vertebrates in the world. In certain species, the internal organs, such as the liver, and sometimes the skin, contain tetrodotoxin which is highly toxic to most animals.

Ongoing research by the Conservation Biology Research Group (CBRG) of the University of Malta studying marine species using genetic techniques apart from morphological features allow for accurate identification of the different puffer fish species as well.

Different puffer fish species have been found in Maltese waters. These include the Lagocephalus lagocephalus commonly known as the Oceanic puffer fish and the Sphoeroides pachygaster known as the Blunthead puffer fish which are toxic and Lagocephalus sceleratus commonly known as the Silver-cheeked toadfish which is even more toxic. For this reason, fishermen should be aware and need to take great care when handling these species.

Maltese fishermen have contacted the CBRG, led by Adriana Vella, PhD (Cambridge) more and more over the past 20 years when finding strange or unknown species of fish in order to be informed about them while contributing to ongoing marine biodiversity conservation studies. Such long-term cooperation has achieved an effective contribution to vital opportunities for knowledge expansion and exchange between researchers and stakeholders such as fishermen.

The Oceanic puffer fish and the Blunthead puffer fish are circumglobal in both tropical and temperate seas including the Mediterranean Sea. The Oceanic puffer fish is often found offshore and is rarely caught by Maltese fishermen. Recently, the first scientific and genetic analysis of an adult specimen of this species was possible after the specimen was forwarded by artisanal fishermen to the CBRG. The Blunthead puffer fish has been caught much more often by local fishermen who have also complained of its impact on fishing gear. Aspects of the CBRG research observations on this species were presented at the International Symposium on Puffer fish held in Turkey in October 2017.

The Silver-cheeked toadfish is of IndoWest Pacific origin and is therefore considered a Lessepsian migrant to the Mediterranean Sea. The latter is very abundant in Eastern Mediterranean and occasionally found in the central Mediterranean. As this species is increasing considerably, it may continue spreading westward and expected to be found more often in Maltese waters in the future.

There are various other species of puffer fish already found in the eastern Mediterranean which the CBRG has also considered in its study together with Turkish researchers in order to recognise and identify these toxic species accurately as they spread in the Mediterranean.

Scientific studies on the genetic identification of various marine species have already been published by the CBRG, and include scientific research results for six species of puffer fish found in the Mediterranean, highlighting the importance of such findings while continuing with further research work on these and other marine species. This was possible with the support of the Ministry for Education, the Ministry for Environment and the Department for Fisheries.

The ongoing research by the CBRG assists better monitoring and management of marine resources and understanding of how changes in marine biodiversity affect the goods and services from which we have been used to benefit. Sea-users, especially fishermen, are welcome to continue cooperating with the CBRG in such vital conservation research work. For further information email: adriana.vella@um.edu.mt or call 9942 9592

Sphoeroides pachygaster

Lagocephalus specimen from Maltese waters