The plight of the anchovy causes me great dismay. The tiny saltwater fish that gives such character to a Caesar salad, warmth to a bagna cauda, backbone to a niçoise and generally perks up the menu of any tapas bar, is near extinction - although it is, apparently, the easiest fish in the sea not to overfish. The adults swim at the surface while the spawning young hang out at the bottom. But boats fish to the depths, preventing the species repairing its own stocks (anchovies are fast-spawning so do repair quickly when left alone).
Sustainability is a buzz word with eco-warriors, journalists and foodies giving ever more advice and opinion on what we should be eating, drinking and thinking amid headlines of global-warming, carbon footprints and runaway food costs.
The fishing industry has got involved too with the launch next Tuesday of its first joint initiative. The Marine Conservation Society (MCS), Marine Stewardship Council (MSC), Seafood Choices Alliance, an international association for sustainable seafood, and Sustain are all pulling together to launch 'Good Catch'. The aim is to help restaurants, caterers and chefs learn more about cooking with lesser-fished species. It also wants to highlight the importance to chefs and caterers of knowing where fish has come from and whether it has been caught through sustainable practices.
Seafood is among the highest risers on our food bills with prices growing as swiftly as catches shrink. In parts of China and Hong Kong, the average weight of any fish caught is now 10g, the result of increasingly sophisticated nets reaching increasingly younger and smaller fish.
Most of us know that supplies are dwindling, but it can be confusing trying to make sense of how to buy and eat fish in a responsible way. It is all too easy to resort to the familiar cod, salmon and tuna, even though we have an inkling that we could be buying more responsibly.
But quite apart from the confusion on what fish to buy, we get conflicting messages on what is the healthy and 'good' option in a more general sense. The media tells us that beef and lamb have huge carbon footprints and are high in saturated fats. Fish, on the other hand, require no fossil fuels to rear them, only using fuel for transport to their markets. Plus, it is high in protein and, in some species like mackerel and sardines, rich in the omega 3 oils that we are told are so good for us.
As obesity rates soar and diets like the Atkins put forward the benefits of eating protein three times a day, fish seems the healthiest option.
Well, there is good and bad news. The bad news is that fish is not quite as healthy as it is cracked up to be. Agricultural fertilisers mean that the seas are now incredibly polluted. Small plankton ingest carcinogens that run off the land; small organisms eat the plankton and small fish eat the organisms. The poisons are magnified each time the process moves up a step in the food chain so that the fish we eat are often high in mercury, nitrates and other man-made poisons. It is also hard to know what fish to buy and what to avoid. Farmed or wild? Pacific or Atlantic? Line-caught or trawled? Fast-spawning or not? Some species are now so endangered that they are best avoided until their stocks have recovered. These include anchovies, most species of tuna, sturgeon caviar, skate, halibut and shark.
Find out the endangered species
Happily, several organisations are now set up to help consumers, restaurants and caterers. The MCS has a brilliant website, fishonline.org, where you can enter a species name and get a rating of how endangered it is. The society also sends out free copies of The Pocket Good Fish Guide, a small neatly-packaged list of species to avoid and new ones to try. These are great to hand out at schools and to stick on fridge doors for an easy, quick reference.
The MSC, set up to provide a way for fisheries to be independently certified as well managed and sustainable, recently relaunched www.fishandkids.org, a child-focused site with information for schools who want to put MSC-certified fish on their menus, easy recipes using sustainable fish, fun and informative games and projects to take part in. It is a great way to engage kids on the subject early on.
Watch for the blue logo
The MSC's blue logo now appears on restaurant and school menus (see box), so you can be sure that you are eating a dish that supports fishermen who operate sustainably. To carry the logo, fish must come from a fishery which has been independently audited to meet the society's standards on whether the species has been caught from an area with healthy stocks and on the way it has been caught (line fishing minimises the impact on habitats and species, whereas trawling does not).
Always ask where your fish comes from
But the single most important thing we can do to protect fish stocks is to question, every time we buy or eat it, where it comes from and whether it has been caught sustainably. Keeping informed about depleted stocks of cod, haddock and tuna around the world involves some work, asking questions doesn't.
Next time you go to the chippy, buy fish at the supermarket or order mussels at your local restaurant, ask if your seafood is MSC-certified or where it comes from and how it was caught (my restaurant, Wahaca, has recently applied for MSC certification for the prawns on our winter menu).
Do this and you send out a message that you care. If we all act today, we will be making sure we can still eat delicious fish tomorrow. For me, it's a no-brainer.
An easy guide to sustainable seafood species
You may not have heard of all of these fish - some come from the waters of Western Australia - but they are the species we should be eating. Bear in mind, however, that some of those listed need to be caught correctly to maintain stocks
Black bream or sea bream (no restrictions)
Clams (hand-gathered only)
Cockles (hand-gathered only or MSC-certified)
Cod, Atlantic (organically farmed only)
Cod, Pacific (MSC-certified only)
Coldwater prawn (MSC-certified from Canada only)
Coley (MSC-certified from Norwegian waters only)
Crab, edible or brown (pot-caught off the Devon coast)
Crab, spider (pot-caught only)
Dab (no restrictions)
Dublin Bay Prawn/langoustine/scampi, MSC-certified, from Loch Torridon only
Flounder (no restrictions)
Gurnard, red and grey
Herring (from Norwegian stocks)
King mackerel or kingfish
Lobster, Baja Californian red rock, MSC-certified
Lobster, Western Australian rock, MSC-certified
Mahi Mahi/Dorado (no restriction)
Mussels (rope-grown or hand-gathered)
Oysters, native and Pacific, farmed only
Pollock (MSC-certified)
Red mullet (not from Mediterranean)
Salmon, Alaskan (MSC-certified)
Salmon, Atlantic (organically farmed)
King scallop (hand-dived only)
Cornish sardines/pilchards
Seabass, MSC-certified; line-caught
Western Australian snapper
Common sole or MSC-certified Dover sole from Hastings, or the Celtic sea
Lemon sole (no restrictions)
Atlantic and European squid (jig-caught only)
Tilapia (farmed)
Rainbow and brown trout (organically farmed only)
Tuna, albacore (MSC-certified from the Pacific only)
Tuna, skipjack (Western and Central Pacific fisheries, and Indian Ocean pole and line-caught only)
From The Marine Conservation Society's Pocket Good Fish Guide
The stamp of approval: MSC logo carriers
Restaurants
Duke of Cambridge, Islington, north London
Konstam at the Prince Albert, King's Cross, London
Moro, Exmouth Market, London
Moshi Moshi, Liverpool Street, London and Brighton
Pissarro's, Hastings
Pret A Manger - 140 stores carrying
Really Wild Salmon sandwich
Compass Catering at Oxford Brookes University, Oxford
Lehman Brothers, London
Wellcome Trust
Westminster School, London
School meal providers
Surrey Commercial Services
London Borough of Tower Hamlets
Hertfordshire Catering
Norfolk Commercial Services
Vale of Glamorgan
Cardiff City Council
London Borough of Havering
London Borough of Hammersmith and Fulham
Caterlink
Coventry City Council
Cheshire County Council
Stockport Council
Clackmannanshire County Council
Hampshire County Council
Nutritionist's verdict
Amanda Ursell
We should eat at least one serving a week of oily fish - sardines, herring, mackerel, trout, salmon and fresh tuna - as they are rich sources of omega 3 fatty acids which help to prevent heart disease and may help to prevent mild depression and to improve problems like dyslexia. Oily fish can contain low levels of pollutants called PCBs and dioxins. Girls and women of child-bearing age should have no more than two portions (140g each) a week. Other women, men and boys can have four. Women who might have a baby should avoid shark and swordfish as they contain the pollutant methyl mercury. Everyone else should stick to one serving. Some omega 3 fatty acids are found in linseed, flaxseed, walnut and rapeseed oils. They may not have the same health benefits as those in oily fish, but are worth consuming if you can't face fish.