You may think you understand your pet, but their secret life is more surprising than we thought…

An academic from the University of Lincoln is one of the leaders of a crack team set up to discover what your cat really gets up to when it leaves the cat flap.

Dr Sarah Ellis was invited to take part in a ground-breaking ”live study”, filmed especially for BBC Two’s Horizon.

Fifty cats in the Surrey village of Shamley Green were put under 24-hour surveillance using GPS collars. Their every movement was recorded, day and night, as they hunted in our backyards and patrolled the garden fences and hedgerows.

The programme, to be screened at 9pm on Thursday, 13th June, will see cats fitted with specially developed GPS collars and cat-cams which reveal their unique view of our world.

Dr Ellis, from the University of Lincoln’s School of Life Sciences, was one of three academics assembled to lead this ambitious experiment for the programme, which will also feature input from five other researchers at Lincoln.

There are over 10 million pet cats in the UK, but what they really get up to when they leave the home has been something of a mystery. In many ways, scientists know more about the roaming behaviour of big cats in Africa than they do about the wanderings of our own pets.

The Horizon project was a collaboration with Professor Alan Wilson from the Royal Veterinary College, whose main research focus is on high speed locomotion in animals. This has recently included work on large cats in Africa.

The problem was how to transfer the technology from the lions of the African savannah to the domestic cats of the British countryside. Using miniaturised lion GPS collars scientists were able to track the cats’ secret journeys day and night, to find out exactly where they go.

The cats also had specially adapted cat-cams, strapped beneath their chins, to give a unique view of what goes on from the animal’s perspective.

Dr Ellis trained the cats to wear the GPS collars and cat-cams, and helped owners interpret the findings, comparing Shamley cat results to current science.

She said: “We collected a huge amount of data, simultaneously over the course of a week, which is potentially the greatest data-set of this sort collated from pet cats. Having decided which cats were most suitable to wear the GPS collars and cameras, we had to prioritise which questions we wanted to answer, what behaviours we should look out for and how we should interpret this data.”

Cats were monitored back in the studio, with help from Lincoln research students, Naima Kasbaoui and Kevin Mahon, who are working on issues associated with roaming cats and its management for their PhDs.

This experiment sheds new light on how cats hunt; what happens when cats square up in our gardens; and how they establish and defend their territories extending over our backyards.

The programme will also feature research into cats’ purring and vocalisation, carried out by Dr Ellis and Dr Oliver Burman from the University of Lincoln, as well as work on the relationships between cats and their owners undertaken by MSc student Alice Potter with Professor Daniel Mills.

A second follow-up broadcast on the main study can be seen on BBC Two at 10pm on Friday, 14th June.