Aggressive and destructive crows that have long been a bane of Japan’s suburbs are finally being warned off in a language they can understand – their own.

Dr Naoki Tsukahara, an expert in biosciences at Utsunomiya University has spent 20 years recording and deciphering the calls made by the birds and is using their own warning cries to convince them that they are in danger.

It is commonplace for hordes of crows to be seen fighting over rubbish on the street after they have torn through clear plastic bags of household waste awaiting collection. 

The abundance of food has also encouraged more crows to roost in suburban parks, where they can become territorial and attack people, particularly in the spring breeding season.

Dr Tsukahara’s company, CrowLab, has created a sensor that can be placed close to a pile of rubbish to detect when a crow approaches. It plays a recording of a cry the birds use to warn each other that danger – a cat, a hawk or even a human – is lurking nearby.

Dr Tsukahara estimates that he recorded 10,000 crow calls before he was able to isolate those that were warnings.

The device, called the Crow Controller was tested in a district of Utsunomiya City, north of Tokyo, between June and September of last year. Footage on the company’s website shows crows looking for the source of danger and flying away without interfering with the rubbish when the recorded calls are played.

Testimonials on the CrowLab web site are glowing, with one resident of Utsunomiya saying it is good to see the birds flying away as it “makes me feel safe”.

The Crow Controller has proved so popular that the company has had to suspend sales as it cannot keep up with demand leading to a six-month wait for deliveries.