Massively outnumbered by the Soviet Black Sea Fleet, the Romanian ships were kept behind the minefields defending Constanța for the next several months, training for the convoy escort mission that would be their primary task for the rest of the war. Beginning on 5 October, the Romanians began laying minefields to defend the route between the Bosphorus and Constanța; the minelayers were protected by the destroyers. After the evacuation of Odessa on 16 October, the Romanians began to clear the Soviet mines defending the port and to lay their own minefields protecting the route between Constanța and Odessa. While escorting a convoy to Odessa on 16–17 December, "Regele Ferdinand" depth-charged and may have sunk the .