C. Tecklenborg yard at Geestemünde, she was launched as the freighter Pungo in 1914 and operated by the Afrikanische Fruchtkompanie for F. Laeisz of Hamburg.

Her conversion took place at Imperial shipyard at Wilhelmshaven in the autumn of 1915, and under the command of Nikolaus zu Dohna-Schlodien, she entered service on 1 November that year.

Möwe slipped out of Wilhelmshaven on 29 December 1915 for her first task, to set a minefield in the Pentland Firth, near the main base of the British Home Fleet at Scapa Flow.

A few days later the pre-dreadnought battleship HMS King Edward VII struck one of the mines; despite attempts to tow her to safety she sank.

This part of her mission complete, Möwe then moved into the Atlantic, operating first between Spain and the Canary Islands, and later off the coast of Brazil.

Möwe was steaming about 120 miles south of Madeira with the merchant steamer Appam, a ship previously captured by the Germans who installed a prize crew and transferred several dozen prisoners of war to her.

Several minutes later, at about 21:00, Möwe came within distance of making out that the smoke had originated from a large merchant ship, later identified as Clan Mactavish.

Clan Mactavish returned fire with her single gun, but repeatedly missed, and the German ship suffered no damage or casualties.

After taking several hits topside, Clan Mactavish caught fire and her captain signalled his surrender to Möwe.

After sinking Clan Mactavish, Möwe reunited with Appam and set a westward course to avoid any Royal Navy cruisers in the area.

In this guise she set out on a series of short cruises during the summer of 1916 to attack Allied shipping off the coast of Norway.

On 6 December 1916, she captured and sank the Canadian Pacific Steamship freighter SS Mount Temple outbound from Halifax to Liverpool.

Mount Temple′s cargo included 700 horses bound for the Canadian Expeditionary Force in France and many crates of dinosaur fossils collected from Alberta's Red Deer River badlands by Charles H. Sternberg destined for the British Museum of Natural History.

Geier operated in this role for six weeks, accounting for two ships sunk, before being disarmed and scuttled by Möwe prior to returning home.

Otaki's captain Archibald Bisset Smith was awarded a posthumous Victoria Cross, finally going down in his ship with the British colours still flying”.

489 Squadron RNZAF at her moorings sheltering off the coast of Norway—near the village of Vadheim in Sogn og Fjordane county.