In Japan’s remote coastal waters, a centuries-old tradition continues as fishers carefully harvest funori and umibudo, two of the country’s rarest and most prized seaweeds. Found mainly along the northern coasts of Hokkaido and the Noto Peninsula, these delicate marine plants grow only in pristine, cold-water habitats that are free from pollution. Funori, a red seaweed once used in textile preservation and as a natural glue in Japanese art, has become scarce due to warming seas and habitat loss. Japan’s annual funori harvest has dropped by over 70% in the past 20 years, prompting local cooperatives to adopt sustainable practices such as rotational harvesting and seaweed aquaculture to preserve the species.
Meanwhile, umibudo, or “sea grapes,” known for their unique bubble-like texture, are mainly cultivated in Okinawa. Farmers there are pioneering land-based seaweed farming systems that recycle seawater and reduce pressure on coral ecosystems. The seaweed industry contributes over ¥30 billion ($200 million USD) annually to Japan’s coastal economy and plays a vital role in carbon sequestration and marine biodiversity. Yet, experts warn that climate change and ocean acidification could threaten future harvests. Efforts are now underway by Japan’s Fisheries Research Agency and local universities to develop heat-resistant seaweed strains, ensuring that these cultural and ecological treasures continue to thrive in the warming seas. More