Wintering in Vannes, we’ve been under massive attack from ficopomaticus enigmaticus, otherwise called the Australian tube worm.
Lovely place to winter afloat, Vannes, right by the old walled town and its markets and restaurants. The main gate through the mediaeval walls overlooks the basin.
Arriving back at the end of October after leaving the boat there three months earlier, we started the engine in neutral but the prop wouldn’t turn at more than idling speed, no matter how open the throttle. We assumed a plastic bag or a rope and asked the Capitain du Port for a number for a diver to clear it.
I’ll organise it for you, he said, and I’ll get you a reduction because I’ve got 10 boats here that need their props cleared and I’ll negotiate a special deal with the diver.
He then explained that the warm autumn weather had led to an explosion in the population of the little tube worm in a harbour that only opens its gates to cold sea water a few hours a day. There’s a small river running into the harbour and – as Wikipedia later told us – this rapidly growing monster especially loves warm brackish water where the salinity changes regularly. The worm makes itself a calcareous tube and grows in colonies like coral. The result is that it can produce something like a coral reef, at worst weighing many tons, and very quickly.
Antifouling stops it but it loves unprotected bronze propellers, plastics, stone and even the backs of crabs. The picture shows it on the pontoon water pipe where it comes out of the water right next to our boat.
The creature was first spotted in the UK in the 1920s, according to DEFRA’s website pages on invasive species, but the South Coast is the limit of its regular habitat, and it is restricted to areas with warm brackish water. There are infestations further north but mainly where the water is both brackish and warm for special reasons eg power station outlets. In southern Brittany it obviously loves the warmer weather that drew us there too.
We antifouled very thickly last year to cover two seasons including a winter afloat, planning just a summer lift out and scrub. But the boatyard at Vannes said we wouldn’t get away with that after wintering in the harbour, so we now need to plan for a proper lift out and antifouling in the spring.
Vannes is by the way a bit more expensive for wintering than the nearby Vilaine, but we decided it was worth it to be able to stay aboard in the middle of a lovely and lively town with a railway station.
A boat between 11 and 11.49 metres pays €1569 for 7 months hivernage afloat from October to April inclusive. The high season charge for August was €575.80, for September €414.70 and the same for next May.
In fact, we’ll leave before 22 May, when they are expecting a thousand visiting boats for the biennial Morbihan week. They’ll be packed as tight as Aussie tube worms on a propellor so we’d rather be elsewhere.
We’ve been a bit lax with the blog this summer, partly because we had mild weather and gentle cruising since we left Cowes in June, and there wasn’t a great deal to report (unless we start doing restaurant reviews?) We went Cowes, Studland Bay, Roscoff, Audierne, Concarneau, the Glenans, and then lots of lovely places including the Vilaine (twice) down as far as Île D’Yeu. Next year we’ll explore further south.