In late January 2020, the University of Otago’s research vessel, Polaris II, cruised down to Broad Bay Stewart Island in response to concerns over the presence of Undaria.

On arrival, snorkelers swam the perimeter of the bay and located 441 Undaria pinnatifida individuals on an artificial structure. Brown seaweed surveys were conducted at both the subtidal and intertidal, with the intention to resurvey this site in one years’ time. Divers eradicated the Undaria individuals, which totalled 90.5kg.