Wild beaver kits born in Devon's River Otter
A wild beaver which is due to be taken into captivity has given birth to three young.
Two adult beavers, one juvenile and the three young, known as kits, are now believed to be living on the River Otter in Devon.
The government had said the beavers would be rehomed, as they could be carrying a disease.
But wildlife campaigners said they hoped to get permission for them to stay.
Sightings of the mammals in the River Otter were believed to be the first of their kind for centuries.
Retired environmental scientist Tom Buckley, who filmed the family, said: "I was so excited to see the female and the kit. It's fantastic stuff.
"Our baby beavers have been born free and their freedom should not be taken away by imprisoning them in a zoo.
"I'd be extremely disappointed if the government did that."
Devon Wildlife Trust said it was working to get a licence from Natural England for the "non-native species" to remain on the river.
The Department for Environment, Food & Rural Affairs said the animals could be carrying a disease "not currently present in the UK".
"We are taking precautionary action by testing the beavers," a spokesman said.
"This will be done with their welfare in mind."
He added the department would wait until the kits were a suitable age before testing them.