Islanders say they cannot escape the mysterious humming
/Islanders in the Outer Hebrides say their lives are being disrupted by a mysterious low frequency humming sound that can be heard day and night.
Lauren-Grace Kirtley, who has set up a Facebook page dedicated to the "Hebridean Hum", said about 200 people on Lewis have reported hearing the noise.
Ms Kirtley said the sound had prevented her from sleeping properly for several weeks, adding: "It's impossible to ignore - it is like somebody shouting in your face constantly for attention."
Marcus-Hazel McGowan, who has been using amateur radio techniques to try and find the source, added: "It's just trying to narrow it down and hoping nobody loses their mind completely over it."
The local council, Comhairle nan Eilean Siar, said it had received reports relating to low frequency sounds from a small number of islanders.
A spokesperson said: "As with any other reports of this nature the comhairle's environmental health team is investigating and will liaise with those who have reported issues."
Ms Kirtley told BBC Radio's Good Morning Scotland programme the hum could be heard across Lewis, adding that it was less noticeable in the centre of the island and strongest on the east coast.
She said it had been recorded at a low frequency of 50hz.
“It is a very low humming, droning, pulsating noise. It’s incredibly intrusive and distressing. I haven’t slept a night through for weeks and have problems concentrating. I get a lot of fluttering in my ears. It’s making me dizzy and giving me headaches.”
Mr McGowan, who moved to the island partly because of the peace and quiet it offered his family, is determined to find the source.
He said electricity company SSEN's Battery Point Power Station in Stornoway had been ruled out as a cause, and he believed it was unlikely to be coming from boats.
The power station is only operated at certain times, while the hum has been reported as a constant problem.
Mr McGowan has heard the noise himself and told Good Morning Scotland: "It is one of those you cannot escape from."
Theories posted on the Facebook page include the cause being a TV mast or tinnitus, a condition that causes ringing and other noises in a person's ear.
It has been suggested the noise of ferries operating between Lewis and the mainland could be carried on a persistent easterly wind.
Data used by BBC Weather suggests there has often been an easterly component to the wind over the past month.
Mating fish
Low-frequency noise has disturbed residents in other places in the past.
Last year, North East Lincolnshire Council said the source of a mysterious humming noise that plagued residents of Immingham may never be discovered.
People said they had heard the low-level sound for a number of years.
In 2013, New Forest District Council investigated reports of a drone-like sound heard on the south coast of England.
One theory advanced at the time was that it might be the mating calls of a certain species of fish.
