ELEVEN life buoys have been found in the river Lee over a seven-day period by a search and rescue organisation.
The Cork City Missing Persons Search and Rescue organisation has urged people now to call gardaí if they see anyone tampering with buoys.
The theft of buoys falls under criminal damage.
An average of 20 buoys a week are stolen in Cork, according to Cork City Council.
The council carries out daily checks to ensure that all of the city's 170 buoys are in place, in different locations across the city. Any buoy that has been removed is replaced.
The cost of a buoy is €50.
There are 1,400 buoys in various locations across the county.
Conviction in the district court under the Criminal Damage Act results in a fine of up to €1,000 and/or up to a year in prison.
However, Fianna Fail senator Keith Swanick is currently seeking legislation to tackle the issue of ring buoy thefts and has drawn up the Life Saving Equipment Bill 2017 which is currently before the Dail.
He drew up the bill following the death of a teenager in Athlone while out swimming. His friends had gone to a local life buoy location but the buoy had been removed.
If enacted, the proposed legislation would also bring in fines of up to €50,000 or jail sentences of up to five years for people convicted for damaging or stealing a lifebuoy.
The legislation would also apply to defibrillators.