Whistling has taken on a sinister tone in Karratha where residents are being asked to report it after a recent spike in burglaries in the Pilbara town.

Officer in Charge Geoff Cramp said offenders had been working in groups, mainly at night, and communicating by whistling to each other.

"They whistle to advise if people are home or not, a lot of the entries are made via unlocked rear doors," he said.

"Whistling seems to be a common factor, they seem to be jumping back fences, whistling to let each other know whether there's a dog in the area or whether there's an unlocked door for entry into a house.

"It just seems to be a bit of a modus operandi that some of the younger offenders are utilising right now."

Karratha resident Claire Hyman said she was unfamiliar with this new use of whistling until moving to the Pilbara last year.

"The first time I heard it I was very confused, and then I saw on Facebook people talking about whistlers which was totally new to me," she said.

Mrs Hyman said she has heard whistling at all hours of the night.

"People start whistling and you can often hear other people whistling back," she said.

"From what I have been told it's to check if people have dogs and so you hear the dogs start going off and the different whistlers going back and forth at each other.

"It's not very pleasant."

Senior Sergeant Cramp said it was a tactic offenders had been using in the Karratha area for up to the past 12 months.

"Unfortunately when we charge offenders and they go into the prison system and they get their heads together and develop new tools that they can utilise for communication rather than yelling out," he said.

Residents told to alert police rather than post first on Facebook

Port Hedland police also reported similar problems with whistlers.

Senior Sergeant Cramp said residents were known to post warnings to each other on social media when the so-called whistlers were out and about, but he also warned residents they should let police know first.

"We have got people on 24/7, a sergeant will answer the phone and we will allocate resources immediately," he said.

"Once we are aware, by all means if they want to let the greater public aware via social media that's fine.

"But unfortunately we can't monitor the social media 24/7, we have got limited resources so we really need to be advised first."

Police say the majority of burglaries were a result of people leaving property unlocked, which had been an ongoing issue.

Senior Sergeant Cramp said police need the public's help to tackle burglaries.

"We are making arrests with forensic abilities, that's assisting us," he said.

"But what we need to do is prevent the incidents occurring in the first place so we need to treat the cause rather than what's happening afterwards.

"We are interested in persons that look out of place, that shouldn't be in a particular area at a given time because it all paints part of a bigger picture that we need to be aware of.

"Now we are heading into the festive season we need to be ensuring that our neighbours are advised if any of us are going away and leaving the premises vacant so they can keep a look out too."