On 17 August, the destroyer performed shore bombardments of the Libyan coast. On 21 August, they did the same at Bardia. In October, "Waterhen" escorted supply ships to Crete, where a forward base was being set up to assist in the Allied reinforcement of Greece. On 25 December, the ship captured the Italian sailing vessel "Tireremo Diritto". On 30 December, "Waterhen" unintentionally rammed and sank the anti-submarine trawler , and was forced to dock for repairs. In April, "Waterhen" became involved in Allied evacuations from Greece and Crete. After this, she was assigned to the Tobruk Ferry Service; supply runs to the Allied force besieged at Tobruk.