Method apparatus and system for controlling fish

A method of capturing a target species using a submersible, wherein the method comprises the steps of:

• providing a submersible comprising:
• (a) a frame;
• (b) one or more thrusters mounted at a back or sides of the frame for manoeuvring the submersible;
• (c) at least one camera connected to the frame for capturing images to allow an identification of an individual of the target species;
• (d) a releasable retractable device;
• (e) a catapult mechanism mounted to the frame, the catapult mechanism being reversibly moveable between a released configuration and a primed configuration by an activatable motor, the catapult mechanism both being configured to be loaded with the releasable retractable device and comprising a clutch and trigger mechanism, the retractable device being attached to a rack of the catapult mechanism and being launchable from the submersible by being propelled by the catapult mechanism;
• and
• (f) a container for receiving a captured individual of the target species;
• wherein the catapult mechanism comprises:
• (i) a rack housing for holding the releasable retractable device;
• (ii) an elastic member for propelling the retractable device, and
• (iii) a pinion gear set comprising a drive gear and a pinion gear, the pinion gear set being configured to be driven through the drive gear by a drive motor;
• and
• wherein,
• (a) when driven starting from the released configuration, the pinion gear engages with the rack to draw back the retractable device and as the rack transitions from the released configuration to the primed configuration the elastic member is stretched and stores potential energy,
• (b) as the catapult mechanism approaches the primed configuration the trigger mechanism engages with a release mechanism,
• (c) the clutch is configured to interact with the pinion gear set to disengage the pinion gear from the rack, thereby readying the catapult mechanism to fire, and
• (d) the rack is releasable to allow the catapult mechanism to move from the primed configuration to the released configuration by disengaging the trigger mechanism and the release mechanism,
• thereby allowing the elastic member to propel the retractable device;
• loading the catapult mechanism with the retractable device and moving the catapult mechanism to the primed configuration;
• manoeuvring the submersible into position wherein the primed catapult mechanism is substantially aligned with a body of an individual of the target species;
• releasing the primed catapult mechanism and retractable device, to attempt capture of the individual of the target species;
• and
• drawing back the catapult mechanism and retractable device, wherein if the capture attempt is successful the retractable device carries the captured individual of the target species to the submersible and the captured individual is dislodged and contained within the submersible.