The “Noto Satoumi” lecture series has been conducted since 2015 as part of the “OUIK Satoumi Movement.” The third lecture was held on December 12, 2015, in Suzu City, Ishikawa Prefecture, with the theme “The Power of the Sea! Shellfish Supporting Satoumi.” For a long time, various fisheries have been active in the waters around Suzu, particularly in the rocky coastal areas, which are ideal habitats for abalone and turban shells. Today, shellfish fishing remains an important livelihood for local fishermen. This lecture covered the ecology of abalone, turban shells, and other shellfish that inhabit Suzu’s Satoumi, fostering presentation and discussion among about 60 participants, including fisheries stakeholders, experts from inside and outside the prefecture, government officials, and local residents.
In her opening remarks, Miki Nagai, Secretary-General of OUIK, introduced the series, noting that it began with the first lecture on seagrass held in Nanao City in July 2015, followed by the second lecture on Satoumi capital theory in Anamizu Town in August, and now the third lecture focused on shellfish in Suzu City.
This lecture series aims to recognize the appeal of Noto’s Satoumi from various fields and perspectives as part of a three-year research activity under the “OUIK Satoumi Movement,” which will be held in nine municipalities in Noto. The series brings in experts from inside and outside the prefecture to consider the conservation and utilization of Noto’s Satoumi resources together with local residents.
Ecology of Abalone and Turban Shells Supporting Satoumi
In the keynote speech, Professor Tomohiko Kawamura, Director of the International Coastal Ocean Research Center at the Atmosphere and Ocean Research Institute of the University of Tokyo, presented on “The Ecology of Abalone and Turban Shells Supporting Satoumi.”
Since ancient times, Japanese people have cherished abalone, and it is common to eat it raw. Japan also excels in the technology for producing dried abalone for export to Asian countries, including China. Additionally, the term “noshi,” used for traditional celebratory wrapping paper, originally refers to “noshi abalone,” symbolizing longevity and used during festive occasions.
While much about abalone’s ecology remains unknown, it is characterized by two eyes and long teeth, allowing it to move rapidly on the sea floor and rocks. The term “abalone” generally refers to a group of large species (such as Haliotis discus, Haliotis divergens, and Haliotis gigantea), with over 100 species found worldwide and around 10 species in Japan. In Noto, species such as black abalone, giant abalone, top shell, and turban shell can be harvested. Today, abalone is farmed worldwide, particularly in South Africa and Australia due to its high market value.
Research has shown that juvenile abalone attach predominantly to a type of seaweed called “bare coral.” As they grow, their habitat and diet change. The 2mm juvenile abalone live on bare coral for about a year, feeding on small algae, while those growing to 30mm move to smaller algae fields, transitioning to larger kelp and wakame forests as they reach 3cm or more. It takes abalone about a year to grow to 1cm, 3-4 years to reach 3-5cm, and 5-6 years to become harvestable at 9-10cm. Abalone can reach an average size of 15cm and live for more than 30 years; however, most large specimens are quickly harvested, resulting in fewer large abalone in the ocean. Moreover, abalone larvae drift in the water for a week, sometimes traveling several kilometers before settling on the ocean floor. Releasing abalone seedlings across neighboring sea areas is more effective for recovery.
Turban shell (Tachypleus tridentatus), a type of small abalone, is another shellfish commonly consumed in Japan. It can reach a maximum size of 10cm, compared to 15-25cm for abalone, and has six to nine respiratory holes, while abalone generally have three to five, resulting in significant price differences based on size.
Conversely, turban shells (Sazae) are a unique species globally, primarily found in Japan and the Korean Peninsula. Although there are over 50 similar species in Japan, only a few are edible. Like abalone, it takes juvenile turban shells about a year to grow to 1cm, reaching a maximum of 10cm in about ten years. Turban larvae settle on seaweed for growth and, once they exceed 5cm, transition to live among larger kelp and wakame forests.
In essence, seaweed serves as both a feeding ground for abalone and turban shells and a refuge from predators such as octopus, crabs, and wrasse. Abalone and turban shells, being the largest and most abundant herbivorous animals in the intertidal zone, play a crucial role similar to “deer (cattle) in the rocky shore,” actively feeding and maintaining the ecosystem, including conditions that facilitate the settlement of bare coral for larval shells.
However, since 1970, the decline in abalone catch has revealed humans to be their greatest threat. Efforts have been made since 1980 to release abalone seedlings, but significant recovery in catch has not been observed. Potential reasons for low recruitment include climate change resulting in colder winter waters and the need to focus on other issues impacting natural recruitment. For example, while densely settled abalone ensure synchronized spawning, harvesting in these areas causes a dispersed population and lowers fertilization rates, leading to poor settling conditions and inadequate food supply for juvenile abalone. Additionally, construction in river basins and along coastlines has caused sediment runoff, adversely affecting the habitats for settling and juvenile abalone. This loss of habitat can have devastating effects on abalone populations.
Fortunately, turban shells and other shellfish are less susceptible to overharvesting due to their lower market prices, which helps maintain a relatively stable density of parent shellfish in the wild, securing natural recruitment. However, to recover abalone resources, it is essential to implement proper harvesting restrictions and utilize seed release while establishing high-density populations of parent shells and protecting the environmental conditions needed for larvae settling.
Shellfish in Suzu and Fishing Rights
In his lecture titled “Shellfish Caught in Suzu and Fishing Rights,” Miyasuke Maeno, a “Fish Meister” with extensive experience in Suzu’s fishing industry, introduced the diverse shellfish found in Suzu’s Satoumi, categorized by habitat: rocky areas, sandy mud, brackish waters, and those floating on the sea surface.
Among the shellfish, turban shell stands out as a representative summer delicacy in Suzu, alongside abalone. Due to active seed release and high harvests, they are affordably priced and become essential in barbecues. While individual units used to be sold in Suzu, they are now priced per kilogram. The current facilities have improved, allowing cooperation with the fishing cooperative for shipping. Conversations with local wholesalers revealed that Suzu’s turban shells compete with those from Kyoto and Tottori but are highly regarded. However, they struggle against efficiently farmed turban shells available from Kyushu, which often meet market demands better. Suzu also ships Hime Sazae, which boast a strong coastal aroma, but demand drops significantly by September when the fragrance diminishes. While there are few issues in Kansai markets regarding the shell shape, the Kanto region prefers those with distinct ridges and thinner shells.
Suzu has the second-highest turban shell catch, with 276.9 tons in 2014, accounting for 60% of Ishikawa Prefecture’s total harvest of 459.7 tons. The primary fishing methods for turban shell include “net fishing,” “diving,” “benthos observation,” and “beach collecting.” For older fishermen unable to operate in deeper waters, collecting shellfish provides a vital source of income.
Suzu is home to numerous edible shellfish, including Matsuba clam, Bekko clams, and others categorized under fishing rights regulations. It is important for those utilizing these resources to confirm fishing rights first. The Japanese fisheries law governs how fish and shellfish are harvested or farmed, and to whom these rights are allocated, aiming to develop fishing productivity. Many mistakenly believe that without fishing rights, one cannot engage in fishing, but in reality, fishery types include “licensed fisheries,” “permitted fisheries,” and “free fisheries,” along with “recreational fishing.” Traditionally, local fishing villages have recognized rights to harvest abalone, turban shells, and seaweed, and this historical order of marine resource use has been passed down through the fishing rights system. Regulations such as closed seasons and minimum sizes for harvesting turban shells (2cm lid diameter, 5cm shell length) and abalone (minimum 10cm) are still enforced, ensuring local fishery resources are managed sustainably.
The OUIK Satoumi Movement
Evonne Yiu, a researcher at the United Nations University OUIK, which specializes in sustainable agriculture, forestry, and fisheries, explained the background and objectives of the OUIK Satoumi Movement. Following the recognition of “Noto Satoyama Satoumi” as a Global Agricultural Heritage System in 2011, conservation activities focused on Satoyama were actively pursued over the last five years. However, there has been misunderstanding regarding the term “agricultural heritage,” which seems disconnected from fisheries, creating an impression among both local residents and many in the fishing industry that Noto GIAHS does not pertain to fisheries. Therefore, to enhance understanding of the allure and significance of Noto’s Satoumi among residents and the prefecture, the “Noto Satoumi Movement” was conceived, kicking off with the first seminar in Kanazawa City in March 2015.
The “Noto Satoumi Movement” aims to promote awareness of the concept of Satoumi, its charm as Noto GIAHS, and the livelihoods of those engaged with the sea. It seeks to establish the Noto region as a hub for research and conservation activities surrounding the Satoumi of the Sea of Japan. By raising the domestic and international profile of Noto’s Satoumi, the movement aims to improve the livelihoods of local households involved in fisheries. Furthermore, it strives to communicate the appeal of Noto’s Satoumi not just in terms of fishing but from various perspectives, including traditional fishing methods, festivals, food culture, biodiversity, and landscape, holding a series of four lectures a year in the Noto region. Experts from both inside and outside the prefecture, as well as local stakeholders, will use these lecture opportunities to share activities related to Satoumi, ultimately contributing to the conservation and utilization of Noto GIAHS.
In the panel discussion, in addition to the aforementioned three speakers, Nobuko Sakamoto, the owner of the traditional inn “Tenzo” and a guesthouse in Suzu City, also participated to discuss the conservation and utilization of Suzu’s Satoumi. Sakamoto, originally from Niigata Prefecture, has operated a restaurant since 2005 serving dishes made from local ingredients, frequently using turban shells, which are popular among visitors from across and beyond the prefecture. While turban shell is commonly served at local tables and consumed regularly, management at Nagahashi Fishing Port, where Sakamoto’s guesthouse is located, actively monitors turban shell harvesting, only allowing collection during the period from May to August to conserve resources. However, there has been minimal discussion on how to reuse turban shells, with common practices involving crafting into ornaments, planters, or dishes but rarely used for compost or other forms of recycling. Many attendees expressed interest in the culinary applications of Suzu’s optimal shellfish varieties highlighted by Maeno and shared thoughts on potential uses.
Kawamura, when asked how connections between Satoyama and Satoumi influence shellfish ecology, noted that while current research is focusing on the “forest-river-satoyama-sea circulation,” studies are still in early stages, and the interactions are not yet understood. However, Japan’s past separation of terrestrial and marine environments has led to ecological degradation; hence some connections should exist. For instance, since both abalone and turban shells avoid freshwater, freshwater flows may impact their habitats.
Finally, Mizuhiro Izumitani, Mayor of Suzu City, delivered closing remarks, noting that while locals are accustomed to the richness of Noto’s Satoumi and may overlook its value, he hopes that this lecture series will lead to a renewed recognition of the abundant resources in Suzu while fostering the conservation of Satoumi resources.
