Every vaporetto stop has them. The routes through the sandbars of the lagoon are marked out by them. Clusters of oak logs, usually in a tripod formation joined at the top by steel bands or chains. The correct terminology for them is bricolle, and they must have quite a lifespan, because although you seen hundreds as you journey between the Venetian isles, I didn’t see any being replaced.
That’s not to say I didn’t see some that must be due for it shortly for the constant lapping of the waves means they rot and erode around the water line by narrowing to a point like some oversized pencil.
That need not be the end of their life though. An Italian furniture design company has begun to produce a range of products from recycled briccola wood, bringing in the likes of Pininfarina, Missoni, and Starck to find new uses.
Ugly ducklings no longer.