Thank a Farmer – Tifenn and Jean Noël Yvon: Breton Oyster Producers Battling the Seasons 15 November 2018 In the Morbihan, on Brittany’s wild Atlantic coast, Tifenn and Jean Noël Yvon, are feeling the effects of the changing climate. These Oyster farmers have noticed a change in the cycles of their oysters, and the operation’s workload has increased as warmer seas trigger changes in the delicate ecosystem.