So long sushi?

By Michael Jones

Bluefin tuna, one of the most popular items on a sushi restaurant menu, has been overfished for many years and the species’ numbers are in a rapid decline.

The latest information from the European Space Agency comes following the oil spill in the Gulf of Mexico, where five million barrels leaked after the Deepwater Horizon oil rig exploded this spring significantly disrupting ecosystems across the entire area.

Alongside the considerable damage done to the coastline and habitats, plankton, sea-floor dwelling species and other microscopic animals throughout the Gulf were substantially affected. Bluefin tuna would not ordinarily be affected as this is not their natural habitat, but they swarm to the area during April and May for spawning season; this was just as the spill was at its most severe.

It has been estimated that up to 82 per cent of the spawning stock has declined over the last 30 years, and this spill may yet prove to be the final nail in the coffin as the popular sushi dish of sashimi tuna may soon be a protected species.

Over 20 per cent of the spawning tuna was estimated to have died within the first few days of hatching, which in turn will have a domino effect on the future of the species, according to data from NASA’s aqua satellite.

David Gugenheim, of the Ocean Federation, added: “This analysis will help us and our colleagues elevate our understanding of these impacts to another level and guide the development of strong policy recommendations.”

There are three types of bluefin tuna, with the Northern Atlantic Bluefin being the most popular in Europe and North America. It is fished from the Gulf of Mexico, the Atlantic and the Mediterranean in particular.

The sustainable limit to the number of Bluefin that can be caught is 7,500 tonnes each year. This is contrary to industry figure of 22,500 tonnes that are currently being taken from the oceans annually. Time is not on the side of the Bluefin. Its fate will now lie not in the hands of Mother Nature, but in the choices made by politicians and poisson preferences by restaurateurs.