More than half of those who needed the coast guard service in 2016 were not wearing lifejackets, according to the end of year statement issued by the Department of Transport.
It also showed that in relation to drownings, adult males continue to be the most vulnerable group.
The statement paid tribute to Caitríona Lucas who was the first volunteer member of the Coast Guard to lose her life on operational service, in a search operation off Kilkee on September 12.
The statement said: "The tragic loss of Volunteer Caitríona Lucas cast a dark shadow over all Coast Guard activities."
The use of 'personal locator beacons' (PLBs) and 'electronic position-indicating radio beacons' (EPIRBs) were responsible for directly saving the lives of five people on the sea in 2016.
Of these, one related to a Coast Guard helicopter rescue of a lone yachtsman, whose yacht had overturned 20 miles south of Co Wexford.
A second related to the location and recovery of three fishermen whose vessel had sunk.
The third incident concerned the location of a single crewed yacht which had become dis-masted off the SW Coast and was subsequently towed to Castletownbere, Co Cork.
However, the incorrect disposal of beacons the owners' thought inactive resulted in 89 false alerts. The Coast Guard has appealed to all EPIRB users to deregister and properly dispose of disused EPIRBs.
Overall the Coast Guard coordinated about 2,500 incidents through its three Marine Rescue Coordination Centres based in Valentia, Malin and its Dublin HQ.
A total of 405 people who were rescued or assisted were categorised as ‘lives saved’ on the basis that the intervention precluded loss of life or severe risk of loss of life.
There was an increase in kayaking and surfing-related incidents with a total of 45 individual incidents requiring a response being recorded. Coast Guard units and helicopters assisted with the recovery of 45 bodies as a result of drowning and other missing person searches.
If you see anybody in trouble at sea, on the coast or on cliffs call 112 and ask for the Coast Guard.