In March 1942 in Scotland, Tui and the four Isles-class trawlers, Killegray, Inchkeith, Sanda and Scarba had been newly built for New Zealand.

When Tui and Moa closed in, those aboard the barges opened fire with machine guns and small arms and got underway.

Moa managed to silence the first barge and sink the last in line with 20 mm (0.79 in) gunfire, then withdrew and attended to the cordite fire and injuries.

Tui then opened fire on the barges, sinking one with her 4-inch gun, and the remaining two escaped inshore in the darkness.

Contact was lost and Tui signalled some US Kingfisher seaplanes of US Scouting Squadron VS-57, based in New Caledonia, to join the search.

A later Naval Board report concluded that "had the proper procedure been followed and a full depth-charge pattern fired in the original attack, there is little doubt but that the submarine would have been destroyed.

[3] COMSOPAC released the New Zealand ships in June 1945, and Tui departed the Solomons escorting a group of six RNZN Fairmiles.

On her return to Auckland, Tui worked with Kiwi and the 7th Trawler Group on the final clearing of the German minefield in the outer Hauraki Gulf.