In a Facebook post on Friday, the Coastguard said people face a fine of up to £500 if caught jumping into the water at any working harbour.
The post was in response to complaints about pier jumping at La Rocque.
The warning was met with anger by many, with more than 340 people posting comments on the JEP’s Facebook page.
Although some people said they supported the statement, others said that pier jumping was a much-loved and harmless Jersey pastime enjoyed by generations of Islanders.
In a new statement issued on Monday, Harbourmaster Captain Bill Sadler said: ‘Ports of Jersey takes it responsibility to ensure the safety of all users of its Harbours very seriously.
‘Pier jumping, also known as tombstoning, is recognised by the RNLI, the Maritime Coastguard Agency and the Royal Society for the Prevention of Accidents as a hazardous activity – resulting in a number of incidents, which required a rescue or emergency response, some of which sadly ended in a fatality.
‘Similar incidents have also been recorded in Jersey.’
He added: ‘While there are a variety of hazards associated with this activity, whether it is from piers, harbour walls or rocks around our coastline, the main ones include striking an object below the surface as well as cold water shock.
‘As part of our year-round ‘Safety @Sea’ campaign we wish to educate water users how to enjoy our fantastic coastline without having this fun change to potential tragedy following an incident which could have been prevented.
‘Participating in activities in groups, with those who have experience with the waters or as a part of an organised activity all minimise the potential for injury – and this is the message we wish to convey.’
He stressed that the authorities were focusing on prevention, rather than prosecuting people.
