All ships over 500 tons have AIS and the majority of fishingboats as well.
In the pleasure fleet there´s an increasing number of boats also carrying AIS.
When entering the AIS guardzone it alerts an alarm. I woke up several times from both targets entering radar guard zone and from AIS alarms.
None of these alarms caused any change of course for Dora Mac but I contacted one ship over VHF to ask about there intention.
I´m impressed by the reliability of these systems.