Kellian Line Setter Sea Trials Initial Performance Testing

The Kellian Line Setter (KLS) is an underwater setting device developed by Dave Kellian, a New Zealand fisherman, and further refined by engineers at the Australian Maritime College (AMC), using their flume tank facility. The KLS consists of a stainless steel cowling and funnel arrangement that incorporates two rollers, and which is towed behind a vessel at depth. The mainline is fed through the cowling, under the first roller and over second roller to stop weights pulling the backbone off the bottom of the first roller. Snoods, floats and weights passed beside the rollers, rather than over them. Initial development of the KLS was previously reported to ACAP in SBWG5 Doc10.
Following assessment of hydrodynamic attributes and functionality of the modified prototype in the controlled environment of a flume tank, further testing and evaluation at sea was has been undertaken under normal fishing conditions. A total of 6 trips have been conducted on board the fishing vessel Kotuku, a 10 m bottom longliner fishing from Tauranga, New Zealand. Each trip involved a series of deployments and test runs, generally in calm sea conditions to measure performance. Initial problems in setting led to the installation of two paravanes on the device to maintain an appropriate depth and angle of pitch for effective fishing when the KLS was deployed.
Before commencing further trials under varying sea conditions, further refinement is planned in the flume tank. These include potentially combining or simplifying the design of the two paravanes, refining the funnel shape to prevent the mainline rubbing on its leading edge, and providing a guide to send weights around the side of the rear roller so that weights on ‘dropper’ ropes can be deployed. Further development in the flume tank will also provide the opportunity to fine tune the funnel shape and paravane settings to optimise performance, prior to continuing further sea trials in New Zealand where operational performance and workability of the setter can be assessed under normal fishing conditions.
The KLS is showing great potential to mitigate seabird bycatch in demersal longline fishing operations, and the SBWG will be kept informed on progress. A detailed report on the initial performance testing of the KLS is provided at Annex 1.