By Ella Davies
Earth News reporter
The crew spotted the kitten when its eyeshine was reflected by their lamps
Two Scottish wildcat kittens have been filmed by a BBC crew.
The notoriously shy animals were filmed at night in the highlands of Scotland.
One of the kittens had an unusual black coat, suggesting that it could have been an incredibly rare dark or "melanistic" genetic form.
The crew, including wildlife presenter Liz Bonnin, had set out to catch a glimpse of the scarce Scottish wildcat. Their footage will be broadcast on the BBC series Autumnwatch.
Wildcat kittens are typically born in April-May
Autumn is a key time of year for sightings as kittens leave their mother's care to establish their own home ranges
They spent two chilly hours "lamping", shining a lamp to catch the reflection in animals' eyes, without success.
But as it approached midnight Frank Law, sporting manager for the Seafield and Strathspey Estates where the search took place, recognised the distinctive "eyeshine" of a cat.
The crew identified a black cat that did not move away as they approached, suggesting it was inexperienced and young.
"The kitten, because it was so young, wasn't looking fearful," said presenter and cat expert Liz Bonnin. Adult wildcats, she explained, are much more wary of humans.
The crew saw another kitten nearby, which had the distinctive striped coat and blunt tail of a Scottish wildcat.
Since the two young kittens were seen together, the team assumed they were from the same family and were waiting at the den for their mother to return from hunting.
Presenter Liz was able to get within 20m of the kittens while the team captured the rare sighting on film.
"It's one thing going out lamping and seeing an adult wildcat - it's quite another to come across a den," she said.
"We got a really good chance to observe this beautiful kitten basically posing for us on a pile of rocks."
Filming Scottish wildcats is a considerable challenge because they are nocturnal and their numbers are decreasing.
How to identify Scottish wildcats
Mysterious black cat
Dr David Hetherington, manager of the Cairngorms Wildcat Project, was called in to confirm the kittens' identification.
The expert agreed that the "tabby-like" kitten was a wildcat but the black kitten presented more of a mystery.
"There is a remote possibility that it is a melanistic pure wildcat," said Dr Hetherington.
Melanistic wildcats are incredibly rare and cannot be identified without genetic testing.
An alternative, and probably more likely explanation for the black kitten found by the BBC crew is that it may be a hybrid of a Scottish wildcat and domestic cat.
Wildcats are known to mate with domesticated felines. In this instance the kitten's black coat could be inherited from a black domestic cat.
This interbreeding or hybridisation threatens the future existence of pure Scottish wildcats,
Felis silvestris grampia.
Their population is estimated at fewer than 400 animals in the wild, making them critically endangered.
Habitat loss, transferral of diseases from domestic cats and traffic collisions also contribute to their rarity.
"They're dealing with a lot of cards against them," said Liz Bonnin.
"Very few people are even aware of the Scottish wildcat. It's hugely important that we conserve them."
Detailed footage of the kittens will be broadcast on
on Thursday 14 October at 2000BST on BBC Two.