Two endangered tiger cubs have been exploring their enclosure, as they were confirmed as being brother and sister.
First-time mother Mishka, aged six, gave birth to the pair at Banham Zoo in Norfolk on October 7.
The Amur tiger cubs have yet to be named, and keepers announced their genders this week – with one male and one female.
There are thought to be around 500 Amur tigers left in the wild, with the species classed as endangered.
She had been identified as a genetically compatible mate for Banham Zoo’s resident male Amur tiger called Kuzma, aged 13.
Amur tigers are the largest of the world’s big cats as well as the heaviest.
Adult males can weigh up to 360kg (56 stone 9lbs) and reach 2.3 metres (7 foot 6ins) in length.
They are solitary animals found primarily in Russia, where they live in forests and have large territories, which they scent-mark to communicate to other tigers.
Due to its Siberian habitat, the Amur tiger has a long coat of fur and a large ruff around its jawline.
Amur tiger mothers seek out secluded den sites to protect their offspring from potential predators and to shelter them form the worst of the elements.
Keepers at Banham Zoo provided Mishka with a purpose-built cubbing box inside one of the dens.
Oliver Lewis-McDonald, team leader of carnivores, said both cubs appear to be developing well.
“The cubs are taking everything in their stride and they’re both confidently moving between all three of their inside dens,” he said.
“Every day they venture a little further outside but remain within the vicinity of the house.
“They have been going out without mum on a few occasions too.
“To have one of each sex is wonderful and we look forward to watching them grow and develop.
“It will be very interesting to see how they differ the older they become.
“At this stage there is little to differentiate their personalities, but the female is very slightly more confident.
“She is definitely the louder of the two!”
They also recently met their father for the first time.
Mr Lewis-McDonald said the introduction was “done at Kuzma’s pace”, and he was given the opportunity to see the cubs through mesh from day one, so he knew they were there.
“After Mishka had been given time to settle and we were confident that her maternal bond with the cubs had been established, he was given access to the den where the cubs were,” Mr Lewis-McDonald added.
“Kuzma chose not to go through to meet them but was more content to let Mishka come to him for a head rub.
“Kuzma is not really interacting with the cubs, but I’m sure this will change as they become more mobile.
“He will become a subject of fascination to them and no doubt they will be following him about.”