Fishing lines: Rising tide of new-age turtle

The very first time I fished the Thames, I saw an otter. Scots and Devonians may see nothing odd in this, but even 40 years ago Thames otters were rare as three-toed sloths. I didn't know this and assumed I would see one every time I took my tackle to the Dorney stretch. I never saw another. Wildlife experts mocked my discovery. A mink, said one. A stoat, said another. What does an 11-year-old kid know?

They had a point. I wasn't just a small human being; I was an angler too, a species notorious for turning sprats into mackerel. Check out those black panthers swimming the Manchester Ship Canal and you'll probably find a fisherman doing the spotting. When it comes to porkie pies, we're right up there with Neil Hamilton. People didn't believe me either when I told them that I had caught a turtle in a Reading pond. Aggressive little blighter bit my finger, so I dropped it and it waddled back into the water. And I had a scratch to prove my story. Over the years, you catch glimpses of creatures untraceable in any British wildlife book - no black panthers, alas - in the form of albinos, hybrids and sub-species. And nobody believes you - except fellow anglers.

I was vindicated this week with news from Froglife that our waterways are seething with exotic reptiles. According to the Suffolk conservation charity, at least five species of alien turtles and terrapins live in UK waters, with 200 ponds and watercourses holding everything from the American red-eared terrapin to the North American snapping turtle. It all started, I guess, with the Mutant Turtle craze (though I remember 20 years ago being told that a terrapin frequented a certain pond). Children soon discovered turtles didn't eat pizza and perform ninja tricks but were really as entertaining as a rock. The youngsters didn't know about suing programme-makers for misrepresentation, so they dumped their boring pets into the local canal or pond.

But terrapins and turtles are hardy creatures, and they survived winters and found plenty of food, from insect life to small fish. And they grew. The one I caught was as big as a dinner plate, but even bigger ones have been spotted. Snapping turtles have been seen as large as 50cm.

You may think it's all adding to our wildlife diversity. Froglife takes the opposite view. It warns that the foreign species could take over the habitat and food supply of native species and cross-breed to produce unwanted sub-species. It's not just terrapins, either. Newts, snakes, frogs and toads are all over the place. The Italian crested newt is cross-breeding with our rare great crested newt, and a sub-species is living happily in Sussex. Green frogs from Europe are said to be out of control in counties like Kent. Then there are American bullfrogs and fire-bellied toads in London, African clawed toads in South Wales and the Isle of Wight, as well as midwife toads in Bedfordshire.

We no longer have just three species of snake, the charity says. Non- poisonous American rat, garter and king snakes have been identified. The Aescupalian snake from southern Europe has taken a shine to North Wales, and there are said to be pythons at large. My Observer Book of Reptiles needs serious updating.

Froglife has won the backing of the Environment Agency and English Nature for an information pamphlet to be published, encouraging the public to look out for foreigners. Anglers will play a key part in this as they have a vested interest in supporting the campaign because certain turtles live almost entirely on fish.

But you have to wonder where it will all end. With our climate getting warmer, I assume that even more exotic reptiles will soon become part of our countryside. Many are already over here. In this week's Exchange and Mart, for example, someone has a collection of iguanas for sale, while other ads talk of chameleons and Burmese pythons. It probably won't be long before anglers have to avoid certain waterways because of the anacondas. And they grow so big that even fishermen won't be accused of exaggerating their size.