What are Guerande Salt Marshes
The salt marshes on the Guerande peninsula are a magical, tranquil place, nestled on the south coast of Brittany, between Guerande and Le Croisic, in the Loire’s estuary. They are a system of salt ponds and water tracts that feed the ponds with sea water. This man made landscape was created centuries ago and became the very important ecosystem on the French Atlantic coast. Their uniqueness and heritage is protected as the Site of Special Interest, Bird Protection Zone and it forms part of European Natura 2000 network. The salt fields patterns are quite mesmerising, especially when viewed from above. They create a picture, labyrinth like, where each pond obtains different hues of green and blue when sun light reflects in its shallows waters.
A History Bit
The Guerande marshes were created sometime in the 9th century, but there are two theories about who came up with the idea of creating a system of evaporation ponds. Brittany is Celtic country, where Breton flags fly proudly and Breton language was spoken until 20th century and is having its revival now. Celtic names of places, are a proof of its history entwined with salt - Guerande comes from Breton Gwenn-Rann, meaning ‘white country”. The locals are proud of their heritage and strongly believe that Breton Celts are the behind the idea of salt ponds.
However, some historians are pointing towards Vikings, who were based just up north, in the neighbouring Normandy. Vikings, the seasoned traders, were very keen to find a good source of salt to sell in Scandinavia and the Baltic region and they had established the salt trade route in the Middle Ages. Since they travelled a lot around Europe, they were able to pick up and spread many ideas around the world. Therefore, some believe Vikings could be the ones who introduced an idea of multiple salt pans instead of a single evaporation pond to Brittany.
After many centuries, there is no point arguing whose idea it was. What matters is that the Guerande peninsula was the only place situated so up north in Europe with such an advantageous climate and environment that allowed a development of salt production through solar evaporation. Since the salt works establishment, the landscape did not change much: salt ponds are tended and harvested manually every summer by paludiers using methods developed in the 9th century.
The Hows of Guerande Salt Marshes
The salt marshes harness gravity, sun and wind to make salt. All salt production happens only in summer months. Les Salinas were built between the level of the high tide to allow sea water in and the low tide to remove winter fresh water before preparing salt works for a new season. The local dark clay is used to line the ponds: it is waterproof and malleable for easy repairs. That clay gives coarse Guerande salt a greyish hue, hence its name: grey salt.
The tidal area where marshes are located, called le traict, has two canals that are opened every 2 weeks to let in new sea water - the Atlantic sea water has 25g/l salt concentration. This water enters vasiere, a reservoir which covers 40% of salt marshes and for 2 weeks it supplies the salt ponds with sea water. Gravity pushes water down to le cobier, where salt concentration rises, so paludiers can remove any algae and crustaceans. These ponds take up about 10% of total area of the salt marshes.
Les Fards, the next stage in a salt journey, are next stage evaporation ponds. Their size is more manageable for maintenance and allows a regular flow of a small film of water. Those ponds are quite flat, which aids greatly salt concentration, with small ditches called les carrieres situated along passageways. Subsequently, water flows into les adernes, which act as daily reserve pools. Salt concentration here nears a saturation and water is released to the salt pans by a distribution channel only for harvest.
On each stage of its journey, water gets heated up and evaporated by sun and wind and finally saturated water 280g/l ends up in les oeillets, legats in Breton, where salt harvest happens. The rectangular oeillets, sized 7m by 10m allow paludiers to collect salt by hand. They could yield up to 50kg of salt a day. The middle of the pond must be very flat while its edge is a dike 1cm by 1.5cm to ensure a required volume of water for harvest. Les oeillets are never allowed to dry out and are topped up with water from les adernes everyday. Paludiers work from les ladures, a small round platforms created in a middle of embankments.
Paludiers gather fleur de sel crystals from an l’oeillet surface on sunny and windy afternoons. Salt crystals only form on water surface and need to be gently scraped with long poles. The coarse sea salt is skilfully gathered from a bottom of salt pan so grey clay is not disturbed. The salt harvesting season lasts here usually from June to August.
Wild Salt Marshes
Guerande salt marshes are a man made landscape, still this landscape is very welcoming and important for wildlife. The salt marshes are a place were birds spend winter and have their offsprings and where migrating birds stop to feed and rest. Here, birdwatchers can observe marsh harriers, avocets, egrets, godwits, herons, terns and more than 280 types of migrating birds which stop every year.
The marshes are also home to less visible world of crustaceans, insects. Thanks to shallow waters, sunlight reaches ponds clay bottoms easily, warming it up and helping plankton to grow.
Along the ponds, there is an abundance of unique flora. The marshes are full of wild fennel and its scent fills the air during warm summer evenings. The marshes are also a perfect salty environment for glasswort, known also as samphire. This succulent, green, twig like plant makes a delicious and sought after side dish. In Guerande, it is quite popular marinated in vinegar and salt or served with sardines rilletts. You can also simply boil or steam it like other green vegetables.
The symmetry and maintained order of the Guerande’s salt pans, creates the unique landscape. The marshes are great, tranquil place to wander, for not only you can witness how the Guerande sea salt is made and collected, but you can discover the vibrant and unusual world of wetlands also.
You can purchase Guerande Sea Salts here.