Canberra-born and raised circus performer Lewie West (patriotically, his mother Sally West gave birth to him at home in Canberra on Australia Day 1988 - our bicentenary) has just won a gold medal at a famous tournament in France.

His mother tells us that he was one of 25 circus performers chosen from 400 applicants worldwide to compete in the Cirque de Demain contest in Paris, just a few days ago. He performs with ensemble circus Circa, which is based in Brisbane, but Circa released him to go and compete in Paris.

His performance specialty includes dangling from straps while performing feats of strength and contortion and for some time he has, as well, been a ''flyer'' who is, his mother explains, a person who flies through the air from others' shoulders and lands with stylish tumbles and somersaults.

But in more recent times, Sally informs, (and look out! Here comes the offending word) he has had a slightly different role.

One day she and her son had this conversation. Sally: ''Gosh, your buttocks are getting bigger!'' Lewie: ''That's because I've got a 'base arse'.''

Then he explained to her that when you develop into being not the flyer but one of those supporting the person who is flying from the human platform, the base, you create bigger, super-strong buttock muscles. You grow the distinctive-looking bottom that his profession gives this unfortunate label.

The Cirque de Demain contest, where he has just triumphed, sounds like a stressful and suspenseful event.

You perform, for judges, in a huge tent containing 6000 souls. And you perform twice (he chose and choreographed his own piece) on two different days.

The elite 25 are whittled down to an even more elite 12 for the gala performance.

He won his gold medal on or around his birthday and rhapsodised to his mum that the win had made for ''the best birthday ever!''

He will be performing with Circa in Canberra in March, and old friends who have not seen him for years may not recognise his transformed bottom.

Circa is a small, different, ensemble circus and if you want to know more, it has a delightful, well-muscled website.

Wednesday's column reported glad tidings that new Australian National University research shows our Cotter River (above the dam, below the dam the story is more complicated) is in ravishingly good health. One of the proofs of the river's vitality, the ANU's Dr Chris Fulton told us, is that it turns out to be home to far more Murray River crayfish than hitherto known.

A history-conscious reader, noting our story, has found a mention of what's almost certainly the same species (but rejoicing in an excitingly different name) in a November 1866 edition of the Queanbeyan Age.

''MURRUMBIDGEE LOBSTERS.

''It is not generally known that fine lobsters inhabit the waters of the Murrumbidgee. We saw, and partook of one this week, which had been taken in that river below Yarralumla. In flavour this delicate fish was equal, if not superior, to the marine species. Its weight was 2lb. 2oz., and its measurement from tip to tip of claws 24 inches, and from head to tail 18 inches. The strength of muscle possessed by this lobster may be illustrated by the fact that before he was captured he not only broke into fragments a fishing-line which he had got foul of, but broke in two an oak fishing-rod one inch in diameter. Similar specimens to the above have lately been captured and brought into town.''

We read this to an appreciative Fulton who thinks that, yes, this was certainly the species of beast that today we know as the Murray River crayfish.

Nothing like it in our waters approaches its size. Neither of us is sure the reporter didn't mean the lobster was taken from the Molonglo rather than the Murrumbidgee (geography has never been one of journalists' strengths) but Fulton thinks it highly likely that this species does still lurk in the Molonglo and so in Lake Burley Griffin, too.