New Zealand Deploys New Tools to Combat Invasive Caulerpa Seaweed

Since its discovery in 2021, the invasive seaweed Caulerpa has spread across parts of New Zealand’s seabed, forming dense meadows that threaten local marine ecosystems. Researchers at the University of Auckland’s Institute of Marine Science, led by doctoral candidate Michele Rogalin‑Henderson, describe the plant as “wily and resilient.” Commercial diver Stephen Te Tai, who removes Caulerpa mainly in the Bay of Islands, notes its seasonal vigor and its cultural significance to the Ngāti Hine Māori community, who view the ocean as integral to their heritage. New Zealand is now assembling a suite of tools—ranging from targeted removal to monitoring—to curb the spread and protect both biodiversity and cultural values.