High-quality passion fruit （Passiflora edulis） with low acidity for fresh consumption is demanded recently. Some recent basic findings have not been fully utilized in commercial passion fruit orchards, and so an understanding of the current situation of commercial orchards is necessary. Therefore, cultivation managements, such as fertilizer application, were interviewed and soil chemical properties, leaf mineral contents, and fruit qualities were measured at 12 commercial orchards on Amami-Oshima Island, a major production area in Japan. The annual and cumulative amounts of N, P２O５, and K２O fertilizer were calculated based on the interview data. Soil samples were collected to determine soil pH, electrical conductivity （EC）, exchangeable Ca, Mg, and K, and available P２O５ content. Leaves were collected to determine the leaf mineral content and SPAD values. Fruits were collected to determine the fruit weight, size, the juice weight, Brix, and titratable acid content. The soil in eight of the 12 orchards had excess available P２O５, and eight orchards had excess exchangeable K compared to the standard values published by Kagoshima Prefecture. The excess available P２O５ decreased Brix. The greater the amount of cattle manure compost applied, the higher the available P２ O５ content, suggesting that excessive compost application was the main cause of available P２ O５ accumulation. Leaf N content was lower than the standard value for high-quality fruit in previous studies. Therefore, increasing the amount of N applied and reducing the amounts of P and K is necessary for producing high-quality fruit. Reducing the amount of cattle manure compost and increasing chemical fertilizer containing N as ammonium sulfate and urea would be effective to this end. In four orchards, the high soil pH might have suppressed vegetative growth. Excess chemical fertilizer and/or the application of topsoil containing shells might have increased soil pH. Yields and fruit diameter decreased with increasing years of passion fruit cultivation. Interveinal yellowing leaves were observed in some orchards, though the cause could not be determined from the soil chemical properties and leaf mineral contents.

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Numerous models and tools have been developed in response to the growing recognition of the importance of incorporating fisherpersons’ behavior and knowledge into fisheries management. This study focused on the Scyllarides squammosus fishery in Amami-Oshima, which is currently experiencing a decline with limited available quantitative catch data. To address this data limitation, a fuzzy cognitive map （FCM） model was used to integrate qualitative knowledge from various stakeholders with existing quantitative data. The objectives were to identify the drivers of the fishery and examine management scenarios. The findings revealed that sea surface temperature and COVID-19 were the primary drivers influencing the fishery. Additionally, a scenario analysis demonstrated that increased management measures may initially boost catches but ultimately lead to the collapse of an already struggling fishery. This study highlighted the utility of the FCM for incorporating qualitative and quantitative information, providing insights into the dynamics and potential management strategies of the S. squammosus fishery in Amami-Oshima.

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Groupers play a significant commercial role in Fiji because they are a highly sought-after food fish. Grouper fisheries in Fiji are currently experiencing sustainability issues. This study explores grouper fisheries in Dravuni Village, Kadavu Province, Fiji, based on structured interviews conducted with fishers. This study identified the characteristics of grouper fisheries in a community context and highlighted the level of understanding of fishers in terms of grouper management. Fishing is the main local economic driver in Dravuni Village and grouper species are captured in a multispecies fishery, and are male dominated, with majority of the fishers engaged seven days per week. The three commonly caught grouper species in Dravuni Village are Epinephelus polyphekadion, Epinephelus fuscoguttatus, and Plectropomus leopardus. Fishers understand the importance of implementing a ban on harvesting during the grouper spawning periods, to protect the grouper stock for the future, as well as protecting spawning aggregations. Fishers identified that more fishing pressure comes from outsiders as well as other villagers. Strong suggestion from fishers indicate community needs more assistance in monitoring its fishing grounds, as well as the need for fisheries managing authorities (Ministry of Fisheries, Fiji) to increase monitoring and enforcement. The information collected adds to the existing knowledge on Fiji’s grouper fishery industry.

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