GIS-based multi-criteria evaluation models for identifying suitable sites for Japanese scallop (Mizuhopecten yessoensis) aquaculture in Funka Bay, southwestern Hokkaido, Japan

Production from Japanese scallop (Mizuhopecten yessoensis) aquaculture is increasing, and supports coastal communities. To ensure both success and long-term sustainability of providing scallop productions, finding suitable sites is an important step in any aquaculture operation. This study was conducted to identify the most suitable sites for hanging culture of Japanese scallop using geographic information system (GIS)-based multi-criteria evaluation models. Remote sensing data (Sea-viewing Wide Field-of-view Sensor (SeaWiFS), Moderate Resolution Imaging Spectroradiometer (MODIS) and Advanced Land Observing Satellite (ALOS)) were used to extract most of the parameters. Seven thematic layers were grouped into two basic requisite for scallop aquaculture, namely biophysical (sea temperature, chlorophyll, suspended sediment and bathymetry) and social–infrastructural (distance to town, pier and land-based facilities). A constraint layer was used to exclude the areas from suitability maps that cannot be allowed to develop scallop aquaculture, including harbor, area near town/industrial and river mouth. A series of GIS models was developed to identify the most suitable areas for scallop culture using multi-criteria evaluation known as weighted linear combination. Suitability scores were ranked on a scale from 1 (least suitable) to 8 (most suitable), and about 56% of the total potential area with bottom depths less than 60 m had the higher scores (scores 7 and 8). These areas were shown to have the optimum condition for scallop culture in this region. The final suitability model outputs were compared with field verification data and found to be consistent.