Fish supply problems lead to novel imports

Another Life:No birds enjoy the air more than intelligent crows, and choughs have by far the most fun.

A morning party - half-a-dozen - came flying along the lip of the dunes, just where the sea breeze was curving up the scarp, and used its lift to bounce like bungee-jumpers, finger-feathers spread in sheer delight.

I have my own occasional game for a fine winter day on the strand, safely played where there's absolutely no one to see and the dog is off chasing rabbits. Between long furls of kelp at the tideline and the fractious collapsings of surf lower down, there's a wide, usually pristine, carpet of sand where a man may walk with his eyes shut, navigating easily by sea-roar and the vermilion blaze of the sun fixed at one corner of an eyelid. A hundred or so blind strides have a pleasantly reckless, even transcendental, effect, before caution insists on a slitty-eyed squint ahead.

One is nearly always doing fine and could go on for miles, but there can be hazards - as in the Christmastide remains of a whale, its final vertebrae stretched on the sand like the rear end of a deliquescent dragon.

The blubber was pocked with bill-marks, the sand around heavily etched by the trampling of gulls and ravens. In the abyssal depths of the ocean there are special, newly-discovered worms that do nothing but recycle dead whales, but here this storm-tossed, mortuary remnant served scavenging birds, like the garden ball of suet for blue-tits.

Beyond it, another flotsam offering, a trigger fish (Balistes carolinensis), was at least whole and recognisable, its big, tough scales proof against all casual assault. Its flattened body (pictured right) swims vertically, like a wavy dinner-plate, and a spine in its dorsal fin locks upright, with the second spine as "trigger". This is a defence against being seized and dragged from seaweedy holes where the fish munches sea urchins with its sharp teeth and thick, prissy lips.

Trigger fish are a southern species, lured north in warmer summers but dying once sea temperatures fall below 12 degrees. I found my first specimen in late autumn of 1989 and their increasing abundance - in lobster pots, for one thing - has been taken as a sign of climate change. But it's not easy to distinguish changes in fish behaviour that are due to global warming from the short-term effects of the North Atlantic Oscillation (our version of the Pacific's El Niño).

Trigger fish, along with other southern species such as longfin tuna and stingrays, may well have been drawn north by the short-term NAO periods of warmth, and such appearances of "rare" sub-tropical species can't necessarily be credited to global climate change (but, of course, it helps).

The long run of storms before Christmas created problems of fish supply in Ireland and produced, even along the west coast, some novel options. As inveterate piscivores, we were seduced by the offer of frozen red snapper (Lutjanus) a rockfish with exotically Hemingwayan associations. The rosy-skinned fillets were firm, sweet and delicious, but ecological misgivings - not to mention thoughts about food-miles - began to stir with the discovery of their origins. The fish was "wild caught" in Vietnam.

Anova, the Dutch company in this particular food chain, specialises in tropical imports, among them mahi mahi (the beautiful dorado, one of the fastest predators in the ocean, a pursuer of flying fish); Nile perch from Africa's Lake Victoria; escolar (a snake mackerel rich in nutritious but somewhat laxative oil) and pangasius, the yellowtail catfish of Vietnam's muddy deltas.

Pangasius is now a leading species among Vietnam's booming fish exports, and is recommended by Anova for its commercially useful "neutral taste" - presumably to bulk out processed fish products with otherwise costly flavours. And the same company takes its first harvest this month from the first big tilapia farm in the Netherlands: tilapia is a fast-growing freshwater fish - a kind of cichlid - already widely raised across the tropics.

Being conscientiously Dutch, Anova is proud of its social duty and of "treating wild fish with respect". "To balance sustainability with demand," its website continues, "requires self- discipline among our fishermen. We therefore disassociate ourselves from fishing by purse seines (enormous nets that encircle whole schools of fish at once), large-scale trawling and hunting fish with sonar, then mass-netting them." Such scruples are all to the good, given some of the recent history of Vietnamese fisheries. Overfishing and destructive techniques have made the country's coral reefs among the most threatened in southeast Asia.

Explosives, chemicals, and electro-rods have been widely used by the poor coastal fishermen, and out at the more remote islands, away from official view, larger operators have been switching to cyanide to drive the last fish - red snapper prominent among them - out of the reefs and into their nets.