The first polar bear cub born in the UK for 25 years is being monitored at a wildlife park.

The Royal Zoological Society of Scotland (RZSS) said its resident female polar bear Victoria has given birth at the Highland Wildlife Park.

The charity described the birth as an “outstanding achievement” but stressed that the first three months can be perilous for polar bear cubs, both in the wild and in captivity.

Staff at RZSS Highland Wildlife Park, at Kincraig near Kingussie, confirmed the birth after hearing “high-pitched sounds” from Victoria’s maternity den.

Una Richardson, the park’s head keeper responsible for carnivores, said: “We first heard promising noises in the week before Christmas and these have now continued into the new year.

“Because we don’t have sight inside her cubbing box we can’t be sure if Victoria has had more than one cub but we can confirm the birth.

“While we are absolutely thrilled, we are not celebrating prematurely as polar bear cubs have a high mortality rate in the first weeks of life due to their undeveloped immune system and the mother’s exaggerated need for privacy, with any disturbance risking the cub being killed or abandoned.

“We will continue to monitor Victoria and very much hope for the best possible news when she emerges around March.

“Until then, Victoria’s enclosure will be closed to the public and keeper activity will be at a minimum to give her offspring every chance of survival.”

New-born polar bear cubs are blind, around 30cm long and weigh little more than a guinea pig, the charity said.

They only open their eyes when they are a month old and are entirely dependent on their mother, feeding on fat-rich milk to grow quickly, weighing around 10 to 12kg by the time they leave their den.

The polar bear breeding season began in March last year, during which Victoria mated with Arktos, one of the park’s two males.

Arktos and Walker, the other male bear, remain on view to visitors to the attraction.

RZSS chief executive Barbara Smith said: “The birth of the first polar bear cub in the UK for a quarter of a century is an outstanding achievement which will arouse interest around the world.

“At RZSS we believe we have a duty to help protect this magnificent species, with the reduction in sea ice, the polar bear’s primary seal hunting platform, predicted to significantly reduce numbers over the next 40 years.

“Our polar bears are part of the European Endangered Species Programme and we hope Victoria’s offspring will survive to reinforce the captive population, which may be needed in the future to augment and help restore a markedly reduced and fragmented wild population.”

Victoria, born in Germany in 1996, previously gave birth at Aalborg Zoo in Denmark in 2008.

She arrived at RZSS Highland Wildlife Park in March 2015.