Mie Spiny Lobster Fishery (Japan)

Abstract

This case study examines the climate resilience of the Japanese spiny lobster fishery in Wagu, Mie, Japan. This fishery is a representative case of Japanese coastal fisheries that exhibit a high degree of harvester collaboration (Ishihara et al., 2021). Ecologically, Kuroshio current plays important roles in larval transport to impact stock recruitment and in water temperature to impact critical seaweed habitat that spiny lobsters depend on (Yamakawa, 1997). Specifically, Kuroshio’s large meander negatively impacts this fishery in both aspects. In recent years, this region has experienced a decline of seaweed bed, termed ‘iso-gare’ or ocean deforestation (Kurashima, 2017). It is likely that climate change-induced ocean warming can exacerbate this. This fishery is data limited and has no formal stock assessment. While the harvesters are highly collaborative and can respond to the changes they observe and experience themselves, lack of scientific information such as stock forecasts limit their ability to plan and take proactive adaptation actions.

Executive Summary

The Japanese spiny lobster fishery in Wagu, Mie, Japan is a co-managed fishery. Like in all other coastal fisheries in Japan, this fishery is managed as a territorial use rights fishery, where harvesters take a lead in the management (Ishihara et al., 2021; Makino & Matsuda, 2005). In Wagu’s spiny lobster fishery (TURF), however, they operate under a unique management regime. Wagu’s lobster fishers have implemented a management regime that consists of two operational schemes. In the first half of the fishing season, the fishery operates under a ‘pooling scheme’ where harvesters pool fishing efforts and landings and share revenues evenly. In the latter half of the fishing season, the fishery operates under a competitive ‘open-access scheme’ where each harvester operates individually and competitively. The fishery has been operating under this regime since the early 2000s, and this regime has contributed to achieve multiple objectives including 1) earning stable income and 2) reducing effort inputs to require less labor activities (Ishihara et al., 2021). These are critical because their stock is volatile as the lobster settlement in their TURF is driven by Kuroshio Current path. Compared to the neighboring TURFs that are both managed bottom-up by harvesters taking lead but operate mostly as open-access throughout the fishing season, Wagu’s landings are more stable over the years (Ishihara et al., 2021).

While the case study examines a very specific fishery, some of the lessons drawn from this fishery can be generalized to understand climate resilience in a fishery that is managed by co-management that has a characteristic of high level of cooperation among harvesters. This fishery also represents data-poor fisheries where routine stock assessment and fishery-specific climate changes are mostly scientifically unknown. Through this case study, I explored what climate resilience looks like in the fishery that is relatively well-managed through fish harvesters exhibiting high levels of cooperation but lacking scientific information.

In recent years, the lobster harvesters in Wagu have reported changes in seaweed habitat that spiny lobsters depend on. The harvesters are experiencing a decline in catch in the offshore and deeper parts of their TURF. A researcher at Mie Prefectural Fisheries Research Institute commented that the region’s water has been warmer due to Kuroshio current meander, and this could be a cause of the changes in seaweed habitat. In broader coastal areas in Mie, a phenomenon called ‘iso-yake’ or coastal deforestation (Kurashima, 2017). No formal scientific studies have been conducted to scope the possibility of this linked to climate change, but a recent increase in water temperatures caused by prolonged period of Kuroshio large meander event seem to be associated with the changes in seaweed habitat. Thus, a possible first impact of climate change will be felt through the changes in seaweed habitat in TURF.

The key attributes and their impact on resilience can be summarized as follows:

• Strong larvae dispersal (ecological 4.1.2.4) and Low genetic diversity (ecological, 4.1.3.3) and Low evolutionary potential (ecological, 4.1.1.3) → opposing impacts
• Low Adult Migration Capacity (ecological, 4.1.2.5), Low Mobility (social-economic, 4.2.2.1), and High Place Attachment (social-economic, 4.2.2.5) → positively impact resilience
• High Social Capital (social-economic, 4.2.2.2), High Agency (social-economic, 4.2.2.4), and Highly Participatory Governance (governance-management, 4.3.2.1) → positively impact resilience
• High Learning Capacity (social-economic, 4.2.4.2), High Resilience Mindset (4.2.5.1), and Highly Responsive Governance (governance-management, 4.3.3.2) , but Limited Access to Knowledge (social-economic, 4.2.4.1) → opposing impacts

Larvae is transported through Kuroshio current system, this means that larvae that are spawn in different regions mix before settling at coastal regions in Japan (Yamakawa, 1997). A study also indicates that no genetic differentiation for this species (Inoue et al., 2007), which I interpreted to indicate a low evolutionary potential. A study have indicated a low adult mobility and stochastic recruitment contribute to the effectiveness of the co-management as the habitat boundary of the adult lobsters match the boundary of the management (Ishihara et al., 2021). Thus, low adult mobility in conjunction with social-economic attributes of low mobility and high place attachment can be regarded as a contributing attribute of resilience. The system also exhibits high social capital, agency, and participatory governance, which can contribute to resilience. However, lack of scientific knowledge limits their ability to take precautionary measures. For instance, lack of routine stock assessment and habitat assessment limit fishers’ ability to plan ahead. These lobster fishers are highly cooperative and have a propensity to take collective action and coordinate their fishing activities to respond to climate change. Yet, these fishers currently can rely on their own experience to adapt. They share their own observations and experience with other fishers in the fishery, thus they are usually ‘on the same page’ and are very observant in terms of noticing ecosystem changes in their TURF as a whole. They also regularly communicate with prefectural researchers and officers as well as some university researchers. Yet, they all lack financial support to conduct formal scientific studies to understand how climate change may impact their fishery. Thus, they are not able to shape adaptation plans for the future.