Emergency ward tench

Rain may have fallen this week, but the drought dilemma continues. And as pond water levels to below last summer's, Britain's first commercial fish rescue service has been launched.

The fish ambulances are two Toyota pick-up trucks customised with 400- gallon fibreglass water tanks fitted with oxygen bottles.

Zac Ludgrove and Tom Harbinson, who founded Sunflower Fisheries in Laxfield, Suffolk, just over a year ago, expect their first emergency calls in about a month's time, when owners of ponds see their carp gobbing desperately for air on the surface. Mr Ludgrove, 24, says: "Low water levels are going to cause chaos".

They have negotiated an agreement with the government's Environment Agencies in Ipswich, Norwich and the Midlands that enables licencees to net last- gasp fish to be processed within 24 hours. It usually takes a fortnight by post. "It would have been a cruelty for them not to agree," says Mr Ludgrove. The pair are prepared for high-speed dashes by road to collect the vital documents.

Their service is free. Not only that, they will buy the fish they rescue. That means owners of ponds, lakes or irrigation reservoirs can turn an environmental crisis into a nice little earner, pocketing anything between pounds 100 and pounds 5,000 for fish that might have died.

Mr Ludgrove and Mr Harbinson, 22, village chums, started their business as a fish exchange rather than a rescue service, cropping surplus fish from domestic ponds and selling them to angling clubs. But last summer the emergency calls began: they rescued 40,000 fish in 20 call-outs.

The infirmaries at Sunflower Fisheries are two 10m- gallon reservoirs newly excavated at a cost of pounds 4,000, and several small holding ponds. When I visited them I saw victims of white carp pox with fungoid scabs the size of 50p pieces swimming near a piped cascade of bright, oxygen- filled water. Such stress diseases, caused by overcrowding and inadequate food and oxygen, are not contagious. But 30 fish from each licensed netting must still be analysed by the Environment Agency.

Fishing is the country's biggest sport, and Mr Ludgrove reckons they could sell an extra pounds 50,000 worth of fish a month - if only they could lay hands on them. As the drought worsens, they may get their chance. (There is certainly no shortage of fishponds. The Ordnance Survey map in their office shows country lanes where nearly every cottage has a pond, sometimes two. The map reminded me of the view from the air, approaching German cities - except that there the ponds are swimming pools.) "We manage 500 to 600 ponds in the area", he says, "but there are many more, some of them unexplored. The fish sitting in them are money to be earned, a great unrealised resource".

Their greatest obstacle is pond-owners' ignorance. TV newsreels about industrial pollution in rivers show silvery dead fish bobbing on the surface. "So pond-owners assume that if no dead fish are to be seen, everything below the surface must be hunky-dory".

But fish killed by lack of oxygen do not float: they lose buoyancy and sink out of sight. The high pressure and humidity of a single thunderstorm can send to the bottom every mature fish in a pond. "We once drove past a farm where we could see the fish gobbing for air and stopped to offer our services to the farmers' wife. She as good as told us to bugger off. But six weeks later she was on the phone in tears. Her fish had died."

Dead fish on the bottom pollute ponds with their oils. "When we net the dead fish out, it's like an oil slick and smells disgusting. The worst thing is, it's preventable."

It takes only three years, he explained, for a pond or lake to reach "stocking density", with the mature fish fiercely competing among themselves for food and oxygen and eating their own spawn. That is the time to crop the fish, before they become stunted and die.

Some waters hold up to 400lb of fish per acre. "So why not earn a few bob?" he suggests. He buys for pounds 4 per lb, for example, any size of tench, a greenish or bronze fish with small scales that competes poorly against carp in the pond but is prized by anglers for its sport. His selling prices per 100: 2in-4in long pounds 60, 8in-10in pounds 375, with reductions for bigger orders. He sells tench over 10in long for pounds 5.85 per lb. "We can sell tench like hot cakes to angling clubs." Other species on offer are carp - common, mirror and crucian - rudd, roach, bream, gudgeon and perch. Their pick- up trucks have delivered fish to clubs as far afield as Scotland.

Mr Ludgrove and Mr Harbinson are not anglers themselves. They see quite enough of the angling fraternity - club members who crowd round the pick- ups as specimen fish of 15lb or more are unloaded, weighing them, posing with them for photographs and arguing over what to name them - Jaws, or Big Bertha, or Twenty Pound Tessie. Mr Ludgrove says: "If I had to go angling at weekends, I'd go mad. I'd just sit on the bank and pull my hair out".

As they don their rubber chest waders and tug at their seine nets - up to 38ft deep, from cork floats down to lead weights - they steel themselves to dredge up plenty besides fish: old bikes, cars, boots. There was even an empty safe once. The police took it away. Their dream is to bring to the surface a crock of gold.

Sunflower Fisheries, Sunflower Farm Barns, Laxfield, near Woodbridge, Suffolk IP13 8HP (01728 638733).