Limitations - VMS
A VMS is one of many tools that can be used in monitoring compliance with fisheries regulations. It is most useful for monitoring compliance with two general groups of management measures, i.e. those pertaining to area and time. Managed areas may be restricted with regard to fishing activity, navigation or other reasons. This might include EEZs, restricted fishing areas, treaty zones, etc. Time regulations may limit activity to defined seasons, or there may be time quotas related to a particular activity, such as "days at sea".
A VMS is of limited use for other types of fisheries regulations. Monitoring compliance with many popular management measures cannot be accomplished with the VMS alone. Examples include gear and vessel configurations, target species, catches and quotas, discards, etc. Traditional inspection and enforcement methods are more effective for these types of requirements.
Although a VMS can make traditional surveillance and enforcement activities more effective, it does not replace them. Aerial and surface patrols and dockside inspections are required for comprehensive MCS. The VMS may, however, aid in the operational aspects of those activities by making them easier to plan and execute.
Traditional surveillance is also required to monitor vessels that are not part of a VMS programme, and vessels with faulty VMS equipment; some of these vessels may be fishing illegally. Traditional surveillance techniques are also required to detect illegal tampering with VMS equipment.