Lantern Net Processing Gear
Scallop aquaculture gear can be heavy and difficult to handle. Especially because scallops are often farmed in lantern nets (cylindrical nets containing multiple growing compartments) that sit tens of feet below the water, it’s difficult to find and process the right nets. At the Hurricane Island Center for Science and Leadership, they are experimenting with using a specialized device called the star wheel to process lantern nets more safely and efficiently.
The star wheel was introduced in Maine by Marsden Brewer, a lobsterman and scallop farmer in Stonington, and refined to fit Hurricane Island’s needs by Silas Rogers, who used to be the facilities manager at Hurricane Island. The design is inspired by specialized gear used on Japanese scallop boats and in Mediterranean longline mussel aquaculture. At Hurricane Island, the star wheel allows the scallop crew to attach longlines of hanging lantern nets to their boat and maneuver up and down the line.
How the Star Wheel Is Used
Two star wheels (one near the front of the boat and another near the back) and a winch are necessary to haul and process a longline of lantern nets. Out on the lease, the crew uses a hook and winch to grab the longline and hoist it up out of the water.
They then lower the line onto the star wheel rollers at either end of the boat. At this point the boat is securely attached to the longline and free to maneuver back and forth along the line using the motor. As the longline rolls over the star wheel, the star’s teeth guide each lantern net line up and over the roller. Without the help of the star shape, each net would have to lifted individually over the roller and the longline would constantly be at risk of slipping back into the water.
How the Star Wheel Is Made
The star wheel itself is made of a fairlead roller designed for a hauler and star-shaped piece of metal welded together. The fairlead is a repurposed 3” lobster pot hauler and the star is cut from a 3/16” stainless steel plate. Along the bottom of the hauler runs a stainless rod that guides the lantern net lines towards the star. The entire star wheel rig is fastened to the boat similarly to how a trailer hitch is fastened to a pickup truck. This way everything can be removed when it’s not needed. The skiff on Hurricane Island has two star wheel rigs, one mounted near the bow of the boat and the other near the stern.
Driving the Scallop Industry Forwards
The star wheel is a great example of innovative gear designed to solve a specific problem. As more people build and test gear like this, each grower can change the dimensions and shape of the design (such as the size and number of teeth on the star) to better fit their specific needs. Even though growing scallops is labor intensive right now, development and testing of equipment like this is what will hopefully lead the industry towards better processing gear in the future.
Innovations articles highlight creative devices or methods on aquaculture farms. They are informed by farm visits and interviews with experienced growers. See our About page for more information.