Only the small habitat off the coast of Taranaki is currently under environmental protection.
Ms Rose said it was an issue at the heart of all New Zealanders, as well as people around the world.
"The broad political spectrum and across all ages want them saved, and call on the Government to do everything that's necessary to protect them and stop them from floating towards extinction" she said.
Members of Labour, Greens and NZ First spoke at the rally, as well as a representative from the Waitakere Ranges Local Board, who pledged funding to dolphin advocacy and protection.
Maui's dolphin are an inshore coastal species with limited home range, slow to breed, and only found in the West Coast of the North Island.
The species has been in rapid decline since the fishing practice of set-netting and trawling was introduced during the 1970s, when the dolphins numbered around 1800.
Only 55 remain, and the International Whaling Commission has warned they could face imminent extinction by 2031.