What is stone bass?
Virtually no-one had heard of stone bass until quite recently, for the very good reason that it did not exist except as an occasional name for a pretty rare fish, the wreckfish. (As TS Eliot might have said, The naming of fish is a difficult matter. It isn’t just one of your family games. You may think at first I’m as mad as a hatter, when I tell you a fish must have twelve different names…) So let’s kick off with some clarification: the stone bass discussed here goes by the Latin name, Argyrosomus regius. Also known as meagre or corvina, it’s pretty rare in the wild and as good as unknown around UK coasts. Wreckfish or Polyprion americanus, is even more rare, but when it does turn up is sometimes known as stone bass, perhaps because the two species look vaguely similar. And both bear a passing resemblance to the far better known and very popular sea bass (Dicentratus labrax).
The English market name of Argyrosomus regius was an issue of no consequence until about 2016 when supplies of a new farmed fish from the Mediterranean began to reach the UK. Now: someone’s offering you 500 boxes a month of a new fish they call “meagre”. Would you think it’s a goer? Or would you do a bit of googling and perhaps alight upon “stone bass”? Voila! Meet the stone bass! So it’s called the stone bass in the UK and the USA, but meagre in international trade.
Meagre in the wild
In its wild state, the meagre is mainly found in the Mediterranean and off west Africa where it has always been a steady but modest component of the mixed fisheries catch. Wild meagre is quite popular in Spain and Portugal, when it’s available, but the supply was always too small to penetrate foreign markets. It is very rare north of Portugal. British marine biologists got quite excited when a small meagre was caught off Cornwall in 1998. Since then a couple of larger fish have been recorded. Some meagre are found in the Red Sea, having reached there via the Suez Canal.
In the wild, the meagre can grow to an impressive 40 kgs. Such a fish would be over a meter long. It's a plain silver fish with one dash of colour - the inside of its mouth is bright yellow. Meagre belongs to a family of fish called Drumfish, named for the sounds they can make. Fishermen know meagre for a very distinct grunting made by male fish during spawning, using "sonic muscles". A big shoal canmake a very loud noise.
A product of aquaculture
In the mid 1990s, a French fish hatchery launched trials with meagre becuase it seemed to show potential for aquaculture by growing very fast. Fish farming works by way of a hatchery growing eggs into small fish (“fry”) which are then moved to fish farming facilities. Fry production is a specialist phase and is only rarely carried out at the fish farm itself. The big challenge at the outset is to identify a procedure that will enable the eggs to be ongrown into fry reliably. The French hatchery worked out a succesful nurturing regime for its eggs, thus opening a new chapter for this fish.
Commercial farming began quite quickly in France and Italy, but only on a small scale because there was only one supplier of fry. However, when word got out about just how efficient the meagre was at converting food into muscle (this is known as the FCR or feed conversion ratio) there was a flurry of interest. Spanish fish farmers got in on the act and by 2011, Spain was the biggest producer of farmed meagre, producing about 60% of the total European aquaculture production of around 2,000 tonnes.
At this point the European Union decided to give the meagre a push by including it with five other fish in a €12m project intended to help fish farms diversify into new species. This five year project was launched in 2013 and its main focus was to identify a good genetic basis for fry production. By this time 13 fish laboratories and hatcheries across the EU had established broodstocks of wild meagre for research and commercialisation. The EU project joined them all up into a Europe-wide effort. Here’s a flavour of what followed, quoted from the March 2015 issue of Aquaculture Europe magazine:
Paired crossings with six pairs of females and males were carried out in the Institute de Recerca I Technologia Agroalimentáries (IRTA, Spain, Dr. N. Duncan). Spawning was induced with GnRHa injections (15 μg Kg-1 for females and 7.5 g kg-1 for males) every 7-10 days. Breeders that did not spawn after 2-3 induced spawning attempts were replaced. A total of 41 different pairs were induced to spawn, of which 10 pairs produced >500,000 eggs, 16 pairs produced >250,000 eggs and 19 pairs produced >100,000 eggs that hatched (Fig. 2). Poor spawning results were not caused by maturity status, repeated spawning or inductions, and different individuals had clear differences in egg production and quality.
The EU project wound up in 2018 having produced the first draft of a complete manual for farming of meagre (which never used the term stone bass once, even in the English translation).
Which hasn’t quite caught on yet
However, interest has faded. Despite the fact that the meagre component of the EU project was run from a top Spanish agri-food research institute (IRTA), Spain’s production of meagre was lower when the project closed than when it started. Nor did it get much further in France or Italy. However there was some takeup in Greece and also in Turkey, because they are the tearaway leaders in farming sea bass and gilt head bream – a large and successful industry in both countries. Indeed they have been so successful that their production has driven prices down to a level where sea bass is available in every large supermarket. So these fish farmers were keen to find a new species, ideally with features that might support a firmer price. And the meagre showed promise because it can be economically grown to two or three kilos (whereas growing sea bass and bream to such a size is not economic). Would you rather eat a 120 gram fillet from a small sea bass or a 200g fillet steak from a large stone bass? Well, you’d probably give the stone bass a try at least.
It was in 2017 that we at The Fish Society first noticed a new fish, stone bass, appearing in our suppliers’ offerings. We immediately ordered some in to trial and it has been a steady seller ever since. It lacks the name recognition and frankly a bit of the taste finesse of sea bass, but it certainly makes a very acceptable meal.
But it’s not making inroads and research for this article eventually uncovered some statistics from the Turkish National Statistical Office showing that Turkish meagre production fell from 3,000 tonnes in 2014 to 1,500 tonnes in 2018.
This may have been due to the fact the Turkish government initially subsidised meagre-farming but phased the subsidies out in around 2016. Over the same period Turkish sea bass production went from 75,000 to 117,000 tonnes and that of gilt head bream virtually doubled to 77,000 tonnes. Corresponding statistics for Greece did not come to light but extensive googling indicates that it’s not taking off there either. Egypt, which has always had a lot of traditional fish farming and is currently completing a reputedly $100m project, “the biggest fish farm in the Middle East”, has also dabbled in meagre but a 2016 report in “Aquaculture International” put its production at 8,000 tonnes against 770,000 tonnes for tilapia.
Stone bass in the kitchen
What does stone bass taste like? It's a low fat fish, pleasant without being really distinctive. It has nice white muscle flakes and of course comes in gratifyingly large steaks, boneless when you buy them from us. We've seen it compared favourably with black cod, but that would be overdoing it. Nevertheless, top chef Michel Roux Jr was happy to give it an outing in a guest article on the Decanter website. He served it raw under an Asian vinaigrette after marinading in juniper berries for 24 hours. And "to add bit of glamour you can add a little caviar..." There's a link to this recipe below.
EU Diversify project 2 (see Estevez PDF)