Fishing Lines: Hooked for life

CATCHING sharks is pretty impressive when you are just 12 years old. Especially when you haul out more than 30 in a day. But it soon reached a stage where I actually got fed up with hooking them, and wished a conger eel or a cod would eat my bait instead. I never realised that I was catching fish that could save lives.

Actually, calling them sharks is stretching the point. Spur dogfish are members of the shark family, it's true, and look a bit like a mini-maneater, but they're about as dangerous as plaice. They average 2lb, swim in big shoals and their ability to gobble up hard-collected bait makes them as unpopular as politicians. When you start to catch dogfish, it's better to move than hope they will go away.

We thought spurdogs were pretty useless in those days. I staggered into school one day with the weekend's catch, offering them to the biology master for dissection purposes. (I will not even try to describe that morning's bus journey, except to say that I had a seat to myself when there were people standing.) Mr Binstead opened the bag, took two steps backwards and changed colour. 'We're all right for dogfish at the moment,' he said, 'but it's a very generous offer, Elliott.'

Taking them home on the bus was out of the question. Leaving them in the classroom was vetoed by everyone else. What was I to do? If I dumped them in the school rubbish bins, it would not take Miss Marple to follow the trail back to me. So I skipped over the fence and dumped the lot in a small stream. Next week the local paper carried a story about dogfish mysteriously appearing in the Thames. I also tried the classic use of that rough dogfish skin. It is supposed to be an excellent substitute for sandpaper, and was once sold as rubskin for polishing wood, alabaster and copper. But it stank like a London subway and left the wood looking as if it had been rubbed down by a cheese-grater.

Spurdog, slightly sinister-looking fish with little piggy eyes, are not bad to eat, although trawlermen dislike them because shoals often attack fish-laden nets. Before the Trade Descriptions Act put paid to lumping all unsavoury-looking fish under the ubiquitous name of rock salmon, most people ate dogfish regularly. And they are interesting fish. Named after two sharp spines in front of their dorsal fins, young spurdogs are born alive after a pregnancy of 18 to 22 months. Its close relative, the spotted dogfish, lays eggs individually in leathery brown cases which beachcombers know as mermaids' purses.

But now spurdogs are set to enjoy a new status with the discovery of a potential new antibiotic in their stomach tissue. The chemical squalamine (the spurdog's Latin name is Squalus acanthias) has a molecule similar to substances already used to tackle parasitic intestine infections. Dr Michael Zasloff, former head of genetics at the National Institute of Child Health and Human Development, in Washington, believes it has wide possibilities for tackling drug-resistant strains of bacteria.

If only Sam Binstead knew what he was turning down when he declined my bag of dogfish.