Lives at risk

Colin Crookshank said the barriers were installed in December, 2004, to stop people jumping or falling into the sea along the east breakwater.

The barriers were ripped out twice in June by youths and thrown into the harbour. Port staff immediately put them back in, but are worried that the advent of the summer holidays will mean they are vandalised again.

Mr Crookshank said: "We are aware that people have been hurt trespassing on our land in the past and we know that there have been fatal injuries at other ports.

"These youths don't seem to realise they are putting themselves in danger. I have CCTV images that clearly show young lads scaling fences and razor wire to climb 30 foot up a tower within the working area of the port and then jump into the water.

"Some have even climbed the navigation light at the entrance to the harbour, before diving off and swimming across the shipping channels.

"The irony is that passers-by may not be able to help anyone in trouble in the water because youths continually remove our lifebuoys and lifelines."

Mr Crookshank said they expected to lose between 20 and 30 lifebuoys over a summer. Six were stolen in one month alone this year.

It cost around 1,000 a year to replace them.

Mr Crookshank said the port authority reviewed safety provisions and equipment regularly. "We will see how people respond this year, but we may have to introduce gates on the approach to the east breakwater."