In the coming years more than fourty species of fish could disappear from the Mediterranean Sea, according the IUCN in a recently published report. These species are classified according the IUCN’s Red List methodology as Critically Endangered, Endangered or Vulnerable. The main threats are overfishing, pollution, habitat degradation and human disturbance.
The IUCN report reviews the conservation status of all native marine fishes occurring in the Mediterranean Sea, based on the assessments for 513 species and 6 subspecies. The assessment was carried out during the course of two expert workshops in 2007 and 2008, and through correspondence with relevant experts. There was not enough data available for almost one-third (151 species) of the Mediterranean marine fishes to estimate their risk of extinction. Only if more data becomes available, the true proportion of threatened species can be calculated, and might be much higher.
It is noteworthy to mention that for those species that are endemic to the Mediterranean Sea, the regional assessments should be considered to be global assessments, as the species represent the entire global population of the species.
Sharks and rays are by far the most threatened class of marine fishes in the Mediterranean Sea, with 31 species (40%) in threatened categories. But also commercial species like Bluefin Tuna, Sea Bass and Hake are considered threatened or near threatened with extinction mainly due to overfishing. The Mediterranean and Eastern Atlantic population of the Atlantic Bluefin Tuna is of particular concern. Overfishing has has caused an estimated 50% decline in this species’ reproduction potential over the past 40 years. Conservation effort for this species has been underminded by lack of compliance with fishing quotas and widespread underreporting of the catch.
The use of fishing techniques and gear, like fishing lines, trawling nets, and illegal driftnets has led to unnecessary by-catch of many animals with no commercial value. These sharks, rays, dolphins, whales, turtles and even specific birds are threatened with extinction too.
The study emphasises the need to review fishing quotas, reinforce fishing regulations, create new marine protected areas, reduce pollution. Next to the need for additional funding of research into the status of endemic Mediterranean marine fish species, and generate data on other data deficient species. (Sources: NRC, 19.04.2011; IUCN, 19.04.2011)