The rocky inshore waters of north Brittany are some of the loveliest cruising in Europe, and they are sown with thousands of small floats that can stop your engine dead. Lobster pots, crab pots, creels: the fishermen call them casiers, and they string them in the shallow, rocky ground around every headland and island along the coast. Each one is marked by a buoy on a length of line, and that line is exactly the right thing to wrap around a turning propeller. Catch one in a tide off the Triagoz or the approaches to Paimpol and you can go from cruising to drifting onto rocks in the space of a minute.
Why the line is the real hazard
The float is not the problem. The problem is what holds the float to the pot on the seabed. A lot of these buoys are tethered with polypropylene line, sometimes with a metal core, and polypropylene floats, which means there is often slack line lying on the surface around the buoy waiting to be sucked into a prop. Wound tight around a spinning shaft, that line does real damage: it can wreck a folding propeller, melt into the shaft seal and tear it, and set up a vibration that tells you something is badly wrong before you even realise what you have caught.
In a strong tide the danger doubles, because the run of water drags the buoy and its line under the surface. The float you would have spotted in slack water is now a foot down, invisible, with its line streaming horizontally straight into your path. Headlands and tidal races, exactly the places north Brittany funnels you through, are where the markers get pulled below the surface and where you are least likely to see them in time.
Spotting them before they spot you
The single best defence is a dedicated lookout. Pot floats are far easier to see from the side of the boat than from behind the wheel, where they vanish under the bow at the last moment. If you have spare crew, station someone on the side deck with the specific job of watching for floats, and tell them to call them early and point. One person steering and watching the chart cannot reliably also catch a small dark buoy bobbing in a chop.
A few habits help. Slow down through known pot grounds, because speed shortens your reaction time and a float seen late is a float already astern of your decision. Keep an especially sharp watch around headlands and in any tidal race, where the markers get dragged under. Cross the worst patches near slack water if you have the choice, both because the floats sit up and because you have steerage to dodge. And use the polarised sunglasses that cut the surface glare; a float you cannot see in raw light often pops out through polarised lenses.
The markers themselves vary. Some are proper buoys with flags, easy to see; plenty are nothing more than a faded plastic fender or a bleach bottle, low in the water and the same grey as the sea. Treat the scruffy, hard-to-see ones as the norm in working grounds, not the exception.
Kit that limits the damage
If you cruise pot-strewn waters regularly, a propeller rope cutter earns its keep. These sit on the shaft and slice through line before it can build into a solid wrap. There are three common types: the disc or rotary cutter, which spins with the shaft and cuts on contact; the scissor type; and the shaver. None is a licence to stop looking out, and none guarantees a clean cut on heavy or metal-cored line, but a cutter often turns a catastrophic wrap into a brief shudder and a freed prop. On a boat that spends its summers off Brittany, I would not be without one.
Clearing a fouled prop
When you do catch one, and over a season in these waters you probably will, the first action is instant and non-negotiable: take the engine out of gear at once. Every second the prop turns winds the line tighter and drives it harder into the seal. Out of gear, then assess.
Sometimes a free line will throw off on its own. With the engine in neutral, a brief, gentle touch of reverse at low revs can unwind and shed a loosely caught rope. If that fails, you are into hand-clearing. You may be able to turn the fouled prop slowly by hand in the opposite direction to unwind it, reaching down from the transom or through an engine hatch on some boats. A line melted into a hard ball will not come off by hand and may need cutting with a serrated blade, a bread knife lashed to a boathook, or extending pruning shears worked from the deck. In the last resort, and only in safe conditions with a tended line on the swimmer, someone goes over the side with a knife.
The danger in all this is not the fouled prop itself but where you are while you deal with it. If you have caught a pot off a rocky headland in a making tide, you can be set down onto the rocks while you are heads-down at the transom. Get an anchor ready, or have a sail you can set to claw off, before you commit to clearing the prop. If you are being carried into danger and cannot free yourself, that is the moment to call for help, and the French distress and safety call procedure should be on a card by your radio so you raise CROSS without fumbling.
Where the worst of it is
The pots cluster on the rocky, productive ground, which in north Brittany is more or less everywhere a yacht wants to be. The pink granite coast around Ploumanac'h and the Sept Iles, the approaches to Paimpol and Lezardrieux through the rocks, the channels around Brehat, the waters off the Triagoz: all of these are working creel grounds. The same broken ground that makes them beautiful and sheltered makes them prime lobster and crab habitat, so the fishermen set their gear exactly where you most want to sail.
Anchorages are not exempt either. You can drop your hook in a quiet bay and find at first light that a fisherman has shot a string of pots across your swinging room, or that you anchored next to a buoy whose line you will pick up when you motor off. Look around before you start the engine in the morning. The buoy that was behind you on a slack tide may be under your stern on the new one.
The other place people come unstuck is the gap between islands and the mainland, the natural short cut, which is often the densest pot ground of all because it is shallow and rocky and easy for a day boat to work. A tempting inside passage can be a carpet of floats. If a channel looks productive for shellfish, assume it is being fished and plan to motor it slowly with a lookout, or take the long way round.
Pots are part of a wider working sea
The same grounds that hold the pots also hold the working boats that set them, and the two hazards go together. The trawlers and potters off this coast move in ways that catch out visitors, and reading their behaviour is its own skill, covered in fishing fleets and trawlers off France. If you are working your way along this rock-strewn shore, the wider pilotage of north Brittany is worth absorbing before you arrive, because the navigation that keeps you off the rocks is the same navigation that keeps your eye on the floats.
There is no clever system for pot markers. There is a lookout, a slow approach through the bad ground, a rope cutter for insurance, and the discipline to declutch the instant you feel that telltale shudder. Get those right and the casiers of north Brittany become a feature of the scenery rather than the thing that ends your cruise on the rocks.
