The wheelhouse contains monitors which display information for the skipper – some are dedicated equipment such as echosounders and radars showing critical parts of the vessel which are not visible from the control position (i.e. winches, power blocks, etc).
Courtesy of Fishing Boat World
Fishing equipment varies in sophistication depending on the size of the vessel and the technology used. Generally, on-board equipment can be categorized into three categories: related to the wheelhouse, to the fishing environment and to handling.
Wheelhouse equipment: this includes equipment for navigation, electronic instruments and communications. It is often clustered around the skipper's chair -- in larger vessels, where the command console is at the centre of the bridge, there is an additional chair for a co-pilot. Main displays are shown on monitors in front of the control position (increasingly shown on one large integrated display); instruments or monitors that are used more infrequently are mounted in the deckhead (ceiling).
Navigational instruments – compass, autopilot, GPS, etc. – are those used for manoeuvering the vessel while at sea and in harbour. Fish detection instruments, such as echosounders and netsounders, are used to search for fish and during the fishing operation. Communication instruments are vitally important for the safety and for general communications (including among crew). These include simple radio devices to EPIRBs and global maritime distress systems.
Environment equipment: this includes devices used during fishing operations, such as medina panels and fisheyes. This equipment can also be fitted to gears, such as Turtle Excluder Devices and Bycatch Reduction Devices, aimed at minimizing adverse impacts to the ecosystem.
Handling equipment: this includes equipment used for on-board fish handling and processing, such as brailers or fish pumps. It also comprises gear handling equipment, such as drums and haulers which are used to spool and bring in nets.