Bears' den: Brief history of Scottish park's polar bears

Walker jumps for a hard hat, one of his favourite playthings

The paw print in the snow was bigger than my head.

On the frozen ground, a little way off, was a yellow construction worker's hard hat that looked like it had been crushed in a vice.

And behind me were two very large polar bears.

Fortunately Arktos and Walker were watching from a securely locked area of their enclosure at the Highland Wildlife Park at Kincraig, near Aviemore.

They were also more interested in the treats their keepers had for them than my guided tour of their paddock, and their toys - hard hats being among their favourites.

The park has been home to Walker since 2010 after arriving from Rhenen Zoo in the Netherlands.

For a time he shared the enclosure with Mercedes, an aged female who had been relocated to the Highlands after 25 years at Edinburgh Zoo.

She grumpily ruled the roost over the then two-year-old boy bear.

Mercedes arrived at the Highland Wildlife Park from Edinburgh Zoo

Mercedes first arrived in Scotland after being captured rather than being shot in Canada in 1984.

During her years in Edinburgh, she reared two cubs, both sired by her partner Barney, who was born at Whipsnade Zoo.

After the death of Barney in 1996, Mercedes lived by herself and was moved to the Highland Wildlife Park's larger enclosure in 2009.

Will baby polar bears emulate the effect tiger cubs had on entries to the park?

Shortly before Mercedes' arrival, the park saw visitor numbers soar following the public unveiling of three rare Amur tiger cubs.

In the space of six months in 2009, the site had a record-breaking 80,000 visits. In the whole of the previous year it had 65,000 visits.

Polar bear cubs will surely have a similar effect on entries.

In April 2011, at the age of 30, Mercedes died.

The following year Vienna Zoo's Arktos arrived at the park as a companion for Walker.

A year older than Walker, Arktos is seen by park staff as a potential mate for a female.

Victoria gave birth to cubs in 2008

Following a process, a female has been selected. Victoria is an 18-year-old bear from Aalborg Zoo in Denmark.

She previously gave birth to cubs in 2008.

Victoria and her first cub, Milak, could be viewed online via a webcam set up in the maternity den.

Last December, Milak was transported to a zoo in Quebec as part of an exchange scheme designed to raise numbers of captive polar bears in Canada.

Now the Highland Wildlife Park is pushing ahead with its plans to raise its own cubs.

If successful, the park could have some much smaller, and less formidable, paw prints in the snow.