Scallop Farming (Ear Hanging and Lantern Nets)

Scallop farming grows Pecten and Patinopecten species from hatchery seed using two principal hanging methods: ear hanging, where a small hole is drilled through the auricle and scallops are attached individually to lines, and lantern nets, stacked circular compartments holding dozens of scallops each suspended from longlines. Seed of 20-30 mm is deployed in spring and grown 18-30 months to 100-130 mm shell height, typically reaching 40-80 g meat weight depending on species and site. Lantern nets allow density adjustment and protection from predators and fouling layers, while ear-hanging maximizes water flow around each animal and growth rate but demands high labor for drilling and handling. Critical husbandry points are density control (roughly 100-150 scallops per 2 m layer at start, halved at intermediate grading), prompt removal of dead shells that foul neighbors, and regular flipping of lantern nets to prevent shell deformation. Summer high-temperature stress above 24-26°C elevates mortality, and sites must be chosen for strong current exchange. Japan and China dominate production, and profitability hinges on half-automated grading plus premium live-market logistics.