Another reason was that the traditional families who owned the majority of the fleet failed to foresee the benefits in participating in the steam ship revolution that significantly cut shipping operational costs through reduced crew and independence of the winds, putting them at a disadvantage vis-รก-vis the new shipping companies of Piraeus, Patras and Syros. A third reason was that the new conditions made illegal activities such as piracy impossible. Once again many of the inhabitants abandoned Hydra, leaving behind their large mansions and beautiful residences, which fell into ruin. The mainstay of the island's economy became fishing for sponge. This brought prosperity again, at least until 1932 when Egypt forbade fishing along its coast. By the Second World War the Hydriotes were again leaving the island; many of them went abroad.
Second World War
Between 1941 and 1943, during the Axis occupation of Greece during World War II, there was famine on Hydra. It is estimated that some eight percent of the population died of starvation
