HexMed Project

SUBMON in collaboration with iSea has joined a team of researchers from 11 Mediterranean countries, that has set up a regional initiative to compile information about the population trend of Bluntnose sixgill shark relying on local ecological knowledge.

The interest in shark conservation has substantially increased worldwide over the last decades. Underpinned by a constant flow of findings concerning the biology of many shark species, their role in the environment and their importance for fisheries as a commercial resource, various conservationists’ initiatives have emerged with the aim of engaging countries in guaranteeing the sustainability and protection of shark populations.

Despite being considered a biodiversity hot-spot for elasmobranchs, the Mediterranean Sea is also home to the highest proportion of threatened species due to unregulated fishing. In a report published in 2016 by the IUCN, 39 of the 73 assessed species of sharks and rays in the Mediterranean were found to be regionally threatened and overfishing was acknowledged as the main driver of decline and local extinction. If you are interested in Sharks and Rays in Greece check this link here!

The Bluntnose sixgill shark (Hexanchus griseus) is a common shark in the Mediterranean and it is the biggest member of its family (reaching up to more than 5 meters). It’s a predominantly commercial deep-water species which can be found in depths up to 2500m and is a bycatch both from bottom and mid-water trawlers, also gillnets, trammel nets, longline, hand lines and other fishing tools.

Although H. griseus has been assessed as “Least Concern” in the Mediterranean by the IUCN, it is protected in Greece by presidential order (Π.Δ. 67/1981) but, the fact that the species can get caught by fishing gears legally in other countries, makes more urgent to monitor its population trend for ensuring its preservation, especially under the current degree of fishing pressure.

iSea is part of the team of marine biologists from up to 11 countries of the Mediterranean (Spain, Algeria, France, Italy, Libya, Tunisia, Montenegro, Albania, Greece, Israel and Cyprus) that has set up a regional initiative to compile systematic ecological information about the population trend of H.griseus relying on local fishermen and their experience in the field. Even though its latest assessment kept it out of the “threatened” category, our aim is to detect whether the species is declining in any of the studied regions given that fishing pressure in the Mediterranean is constantly increasing.

This project is funded by the Shark Foundation.