For Longline Fishermen This device came about as a result of an enquiry from a Patagonian toothfish company. They experience predation,  mainly from Orcas, of up to 80% of their hooked catch, particularly when using the standard Spanish longline  configuration. Depredation is reduced when using other longline systems such as the Chilean “Cachalotera” system  but it appears that the Orcas develop new skills to work around this i.e. one Orca pushes the cachalotera up off the fish while another takes it off the hook.  The “My-Fishi Shuttle” anti-depredation device is based on  the principle of stripping the fish off the longline as it is  hauled up and encapsulating them in a mechanical structure  which is impenetrable to the Orcas and other predators.     In its most basic form, there is internally a simple  mechanism that strips the fish off the hooks, a trap door  through which the fish then pass into the containment area  and a hatch through which the fish are removed when the  shuttle is hauled on board. The cut-outs in the outer skin do provide some size  selectivity and hence their shape and size is tailored to the  target species. It is a purely mechanical device - no motors, electronics or  sensors. In operation, the longline is set in the normal way. At haul time, after the anchor has been brought on board the  shuttle is put onto the mainline. The mainline is then fed to the line hauler and the hauling process started. The  shuttle, which may be attached to a separate haul line, is then put over the side. As it travels downwards it will first pass through the depredation zone when the predators can attack the hooked fish. It would then enter its operational zone i.e. from the bottom of the depredation zone to just above the sea bed. As  the shuttle moves downwards, the mainline (and other branchlines, snap lines, additional lines and snoods) move  upwards through the center of the shuttle. The downward movement of the shuttle though the water column creates a strong water flow through the shuttle. If there is a fish on a hook entering the shuttle, it will be stripped off by the hook stripper. The water flow will force the unhooked fish through the fish hatch in the shuttle and into the  containment area. This process will continue until the shuttle reaches the seabed or some set depth.  At this point, the direction of the shuttle is reversed and it is hauled upwards towards the vessel. The water flow  direction also reverses, holding the trap door closed. The shuttle should be hauled up faster than the longline itself so that it reaches the top of its operational zone before any fish do. Once there, the direction of the shuttle is reversed again, repeating the cycle. After a predetermined number of cycles or when all the hooks have been through the  shuttle, it can be hauled back onto the vessel and the fish removed through a locked fish removal hatch. The My-Fishi Shuttle offers the following benefits: o Can be attached and detached to the longline at any time during the fishing operation o Only one device per vessel required o Able to handle most longline configurations o Some selectivity - (determined by cut-out shape and size) o No foul-hooking of fish once they are in the containment pod area o Can be used from either end of the longline o Opening and closing of hatch controlled by water flow - no fancy mechatronics o Predators should come off second best if they try to "engage" the device o No potentially ear-damaging acoustics o Should not significantly slow down the hauling operation o Compatible with autoline systems For more detailed information or to discuss your specific requirements please contact Active Fishing Systems.   
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