The world’s first wireless monitoring system for scallop dredges has been introduced – and data from one vessel indicated a 22% increase in catch.
The Dredgemaster system has been developed by Notus Electronics Ltd in coordination with the scallop industry and consists of an acoustic receiver and computer in the wheel house, a hydrophone and sensors mounted on the dredge. Communication between the sensors and vessel is wireless.
A major partner in development was the FV Captain Ryan from North Carolina, USA. Over the last 13 months, the Captain Ryan has used the Dredgemaster. The most important parameters measured are warp length, pitch angle and roll angle.
Warp length is measured on both dredges and has an accuracy better than 0.5m. Warp out is a major determinant of the dredge’s pitch angle (forward/backward angle). Pitch determines how well the dredge fishes. For example, the FV Captain Ryan determined that the optimal pitch angle was 9°. Shooting just a mark too short would result in a 14° pitch and reduced fishing. Likewise, speed of the vessel greatly determines the dredge’s pitch.
The results of monitoring the dredges angle showed positive results. The FV Captain Ryan set one dredge according to Notus reading and the other dredge was fished ‘the old way’. Data was recorded over an entire day and Notus clearly demonstrated a 22% increase.
Roll angle is also monitored which instantly detects if the dredge flips during shooting. Other options available are a club stick sensor, depth, dredge spread and temperature.
