Bird-class minesweeper

The Bird-class minesweeper was a naval trawler built to Admiralty specifications so it could function as a minesweeper. Forty-five were built. The RNZN ships were also referred to as corvettes.

The Bird class evolved from the experimental MS trawler HMS Basset, 1935, followed by HMS Mastiff, 1938, both built by Henry Robb Ltd. They were slightly larger and more powerful than these prototypes of what ultimately became the ''Isles' class.

Royal New Zealand Navy ships

 * HMNZS Kiwi (T102)
 * HMNZS Moa (T233)
 * HMNZS Tui (T234)

Second World War
On 29 January 1943, in a classic duel, Kiwi and Moa rammed and wrecked the Japanese submarine I-1. On 19 August 1943 Tui and some US Kingfisher float-planes jointly sank the Japanese submarine I-17.